We determined the sequence of mitochondrial Cytochrome oxidase subunit I （CO1） in two Drosophila melanogaster strains originating at ＂Evolution Canyon＂, Israel. CO1 nucleotide sequences from two iso-female strains...We determined the sequence of mitochondrial Cytochrome oxidase subunit I （CO1） in two Drosophila melanogaster strains originating at ＂Evolution Canyon＂, Israel. CO1 nucleotide sequences from two iso-female strains, 2-1 and 6-1, were 1,534 and 1,543 base-pairs, respectively. In each strain, ATAA was used in initiation of translation. Exchange rates for nucleotide and amino acid sequences were larger in the 6-1 strain than in the 2-1 strain when Oregon-R was used as the standard. Non-synonymous exchange rate was larger than synonymous exchange rate among the three strains.展开更多
To assess the population development of submerged plant species in disturbed lake ecosystems,we need to better understand the genetic diversity and spatial genetic structure at a fine scale,as well as the impact of di...To assess the population development of submerged plant species in disturbed lake ecosystems,we need to better understand the genetic diversity and spatial genetic structure at a fine scale,as well as the impact of disturbances on the populations.Caohai Lake,in southwest China,is a suitable natural sampling lake because of its abundance of submerged plants and the intense human disturbance.Three widely distributed species,Potamogeton lucens,Ceratophyllum demersum,and Myriophyllum spicatum,were sampled;the spatial position of each individual was recorded in two-dimensional coordinates;and the species were analyzed genetically using microsatellite markers.Among the species studied,M.spicatum exhibited the highest genetic and clonal diversities.All P.lucens subpopulations but one showed a significant fine-scale spatial genetic structure(FSGS),which may result from the limited gene dispersal.However,M.spicatum and C.demersum,with a relatively large distance of gene dispersal,had no significant FSGS.The FSGS pattern of P.lucens at the dock site with intense boat disturbance was significantly different from that at other sites.Our results imply that the FSGS of submerged plants is affected by many factors including seed dispersal,vegetative reproduction and disturbance from birds and boats.Most subpopulations of the three species hadσ_(sex)^(2)/σ_(veg)^(2)values greater than one,implying that the sexual dispersal contributes more than vegetative dispersal to total gene dispersal.Therefore,it is worth paying attention to the importance of seed dispersal for population development of submerged plants in lake ecosystems.展开更多
All vertebrates have a definitive thyroid gland,or thyroid for short.As a critical organ for growth,development and metabolism,its origin and evolution have long received attention.On the basis of anatomical position,...All vertebrates have a definitive thyroid gland,or thyroid for short.As a critical organ for growth,development and metabolism,its origin and evolution have long received attention.On the basis of anatomical position,endodermal origination and histological features,the endostyle of amphioxus has been proposed as a homologue to the thyroid of vertebrates.This homology is further supported by the findings that the amphioxus endostyle abounds in thyroid hormones,possesses several thyroid-specific proteins such as thyroperoxidase,nicotinamide adenine dinucleotide phosphate(NADPH)oxidase and thyroglobulin,and expresses the thyroid-related transcription factors involved in the regulation of development of the vertebrate thyroid,including Nkx2.1,FoxE4 and Pax2/5/8.Importantly,our study on functionality,together with others,indicates significant similarities between the amphioxus endostyle and the vertebrate thyroid gland.Moreover,we show that the production of thyroid hormones by the amphioxus endostyle is mediated in a fashion similar to that of the vertebrate thyroid.These provide solid evidences that the amphioxus endostyle is the homologue of the vertebrate thyroid.From a phylogenetic viewpoint,we propose that the hypobranchial ridge,or endostyle-like structure,of hemichordates is the most primitive forerunner of the thyroid,from which the vertebrate thyroid is formed through the transformation of non-follicular endostyle of amphioxus to follicular endocrine organ of vertebrates.We also raise a couple of questions that demand further study.展开更多
Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability ...Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability of surrounding microbiomes have still not been de-termined.Here,the prokaryotic microbial community network stability and assembly char-acteristics were systematically analyzed and compared between the green tide and non-green tide periods.U.prolifera blooms weaken the community complexity and robustness of surrounding microbiomes,increasing fragmentation and decreasing diversity.Bacteria and archaea exhibited distinct community distributions and assembly patterns under the influ-ence of green tides,and bacterial communities were more sensitive to outbreaks of green tides.The bacterial communities exhibited a greater niche breadth and a lower phyloge-netic distance during the occurrence of U.prolifera green tides compared to those during the non-green tide period while archaeal communities remained unchanged,suggesting that the bacterial communities underwent stronger homogeneous selection and more sensitive to green tide blooms than the archaeal communities.Piecewise structural equation model analysis revealed that the different responses of major prokaryotic microbial groups,such as Cyanobacteria,to environmental variables during green tides,were influenced by the variations in pH and nitrate during green tides and correlated with the salinity gradient during the non-green tide period.This study elucidates the response of the adaptability,associations,and stability of surrounding microbiomes to outbreaks of U.prolifera green tides.展开更多
Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in humans.Previous studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusio...Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in humans.Previous studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusion and size of lipid droplets.Nannochloropsis oceanica is a model oleaginous microalga with the accumulation potential of fatty acids.We believe that the SEIPIN homolog if any in N.oceanica should function as it does in humans,plant among others.In this study,we identified a homologous gene of SEIPIN in N.oceanica,constructed a bacterial plasmid containing the elements controlling the transcription of its complete antisense RNA,and integrated the linearized plasmid into the N.oceanica genome.We obtained a transformant in which the abundance of SEIPIN transcript is significantly down-regulated.Flow cytometry analysis showed that the triacylglycerol(TAG)content of the transformant is significantly lower than that of the wild type(WT).Transcriptomic analysis showed that the down-regulation of SEIPIN transcript abundance could affect the protein functioning in endoplasmic reticulum(ER),implying that SEIPIN gene can function in N.oceanica in a similar way to that in A.thaliana.展开更多
Pseudoalteromonas is a group of marine bacteria widespread in diverse marine sediments,producing a wide range of bioactive compounds.However,only a limited number of Pseudoalteromonas phages have been isolated and stu...Pseudoalteromonas is a group of marine bacteria widespread in diverse marine sediments,producing a wide range of bioactive compounds.However,only a limited number of Pseudoalteromonas phages have been isolated and studied.In this study,a novel lytic Pseudoalteromonas phage,denoted as vB_PalP_Y7,was isolated from sewage samples collected at the Seafood Market in Qingdao,China.vB_PalP_Y7 remained stable across a wide range of temperatures(-20–50℃)and a wide pH range(3–12).The vB_PalP_Y7 phage harbors a linear double-stranded DNA molecule of 57699 base pairs(bp)with a G+C content of 45.90%.Furthermore,it is predicted to contain 58 open reading frames(ORFs).Phylogenetic analysis and protein network relationship analysis revealed low similarity between vB_PalP_Y7 and viruses in the ICTV and IMG/VR4 database,suggesting that vB_PalP_Y7 may be a potential new genus,Miuvirus.This study contributed valuable insights to comprehend the relationship between Pseudoalteromonas phages and their host organisms.展开更多
A new record of Platycephalus sp.1 （sensu Nakabo, 2002） was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongyi...A new record of Platycephalus sp.1 （sensu Nakabo, 2002） was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp. 1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit （COI） gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp. 1 was 0.1%. Net evolutionary distances between Platycephalus sp. 1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COl sequence analysis strongly supports the validity ofPlatyceohalus sp. 1 at genetic level.展开更多
Biological soil crusts are essential components of arid ecosystems. We examined the variations in microfungal communities inhabiting different biological crust types in the vicinity of the Shapotou Research Station in...Biological soil crusts are essential components of arid ecosystems. We examined the variations in microfungal communities inhabiting different biological crust types in the vicinity of the Shapotou Research Station in the Tengger Desert, China. A total of 134 species from 66 genera were isolated using the soil dilution plate method. The mycobiota of the crusts from the Tengger Desert, similar to that of the Negev Desert in Israel, was dominated by melanin-containing species with large multicellular spores. Abundance of these xeric species increased spatially with increasing xeric conditions from moss-dominated to cyanobacterial crusts. Density of microfungal isolates displayed the opposite trend and was positively correlated with chlorophyll content, indicating the possible significant influence of organic matter content and wetness duration on fungal biomass. Within a chronosequence of the localities of different periods after sand stabilization with revegetation, little variations were revealed in species composition and isolate density of the crust microfungal communities, while a tendency towards a decrease in the community diversity level with the crust age was noted Microfungal communities from stabilized localities differed from those of the natural localities in abundance of the dominant and some frequent species, and in the fluctuations of diversity characteristics between the cyanobacterial and moss-dominated crusts. The variations in mycobiotie parameters in the soil crusts of the Tengger Desert were apparently associated with the topographically induced variations in abiotic conditions, while the differences in microfungal community of soil crusts between the Tengger and Negev deserts, such as the significantly higher abundance of thermotolerant species in the crusts of the Tengger Deserts, were caused by the principal differences in their precipitation regimes, associated with different rainy seasons, winter and summer in the Negev and Tengger deserts, respectively.展开更多
Octopus minor is widely distributed along the northern coast of China. To date, there is little information on the prey selection process of this species. To understand this process, several experiments were carried o...Octopus minor is widely distributed along the northern coast of China. To date, there is little information on the prey selection process of this species. To understand this process, several experiments were carried out. Three types of bivalves, namely, Ruditapes philippinarum , Mactra chinensis , and Mytilus galloprovincialis , were used to observe the prey selection of O . minor and to analyze the potential causes of prey selection from three aspects: prey profi tability, adductor muscle tension and handling time. Under single-prey conditions, we found that the average (±SD) predation rates of O . minor on R . philippinarum , M . chinensis , and M . galloprovincialis were 1.73±0.50, 1.27±0.42, and 0.8±0.2/d, respectively. Under diff erent prey combinations, octopods actively selected one type of prey over the other(s), and the order of prey preference was R . philippinarum , followed by M . chinensis and lastly M. galloprovincialis . Furthermore, the shells of the consumed prey showed that O . minor only consumed bivalves by pulling them apart since there was no evidence of drill holes on the shells. The prey selection of O . minor was related to the prey profi tability and handling time;O . minor appeared to select preys with a higher profi tability and a shorter handling time. However, the diffi culty in opening the bivalve was not consistent with the prey preference of the octopods. These results suggest that O . minor prefers to consume R . philippinarum possibly due to a high profi tability and a short handling time that supports the optimum Foraging Theory.展开更多
Diabetes mellitus(DM) is the third most common noninfectious disease leading to early disability and high mortality. Moreover, the number of patients is growing every year. The main symptom of DM is hyperglycemia. Inc...Diabetes mellitus(DM) is the third most common noninfectious disease leading to early disability and high mortality. Moreover, the number of patients is growing every year. The main symptom of DM is hyperglycemia. Increased levels of blood glucose activate polyol, hexosamine, and protein kinase metabolic pathways cause the intensification of non-enzymatic glycosylation and nitration of macromolecules. This, in turn, leads to the development of oxidative and nitrative stresses and secondary complications, such as different kinds of microand macroangiopathies. Metabolic disorders caused by insulin deficiency in diabetes significantly impede the functioning of a homeostasis system, which change the physical, biochemical, morphological, and functional properties of blood cells. As a result, the oxygen-transport function of red blood cells(RBCs), rheological properties of the blood, and functions of immunocompetent cells as well as the process of apoptosis are primarily affected. Modern pharmacotherapy focuses on the search for new preparations that aim to decrease blood glucose levels. Undesirable side effects and adverse reactions caused by synthetic medicines led to the search and investigation of new preparations of natural origin. Medicinal mushrooms play an important role among such new preparations. They are a source of a large number of high-and lowmolecular compounds with pronounced biological effects. Our investigations show pronounced hypoglycemic and anti-anemic action of submerged cultivated mycelium powder of medicinal mushrooms Agaricus brasiliensis(A. brasiliensis) and Ganoderma lucidum(G. lucidum) on streptozotocin-induced DM in rats. Also, we showed that mycelium powders have membrane protective properties as evidenced by the redistribution of RBC populations towards the growth of full functional cell numbers. Normalization of parameters of leukocyte formula and suppression of apoptosis of white blood cells in diabeticrats treated with A. brasiliensis and G. lucidum mycelia indicates pronounced positive effects of these strains of mushrooms. Thus, the use of medicinal mushrooms for treatment of DM and in prevention development of its secondary complications might be a new effective approach of this disease's cure. This article is aimed at summarizing and analyzing the literature data and basic achievements concerning DM type 1 treatment using medicinal mushrooms and showing the results obtained in our research.展开更多
We documented the pattern of cell development in Euplotes charon. The ontogenesis of this species was similar to many of its congeners, except for the formation of the caudal cirri. In E. Charon, a caudal cirrus is fo...We documented the pattern of cell development in Euplotes charon. The ontogenesis of this species was similar to many of its congeners, except for the formation of the caudal cirri. In E. Charon, a caudal cirrus is formed posterior to each of the rightmost two or three dorsal kinety anlage in the proter, and the second rightmost dorsal kinety in the opisthe. In addition, two caudal cirri are formed posterior to the rightmost dorsal kinety in the opisthe. This pattern of development represents a completely new type. Based on our evaluation, and in comparison with previous studies, we also conclude that the pattern of cell development is variable among species in the Euplotes genera. The variation is particularly evident during the formation of frontoventral and caudal cirri. Based on the segmentation pattern of frontal-midventral transverse cirral anlagen, cirri reduction, and migration of frontoventral cirri, we identified five types: the affinis-type, the eurystomus-type, the charon-type, the raikovi-type and orientalis-type. Euplotes (s. l.) can also be divided into three types based on the formation of caudal cirri: focardii-type, vannus-type and charon-type. Indeed, we conclude that the number (one or two) of marginal cirri should be given as much consideration as the genetic separation. Given this, we reassessed the validity of using genetic separation to classify the group. Generally, the morphogenetic data disagreed with the molecular data (SSrRNA gene sequences). Given these discrepancies, it is too early to draw conclusions on the systematic arrangement of this species-rich taxon.展开更多
Nannochloropsis oceanica promises to be an industrial-level producer of polyunsaturated fatty acids. In this study, the fastest and slowest growing N. oceanica mutants were selected through N-methyl-N＇-nitro-N-nitros...Nannochloropsis oceanica promises to be an industrial-level producer of polyunsaturated fatty acids. In this study, the fastest and slowest growing N. oceanica mutants were selected through N-methyl-N＇-nitro-N-nitrosoguanidine mutation, and two mutant strains and the wild type （WT） subjected to transcriptome profiling. It was found that the 0D680 reads at stationary growth phase of both WT and its mutants were proportional to their cell density, thus indicating their division rate and growth speed during culture. This chemical mutation was effective for improving growth performance, and the fast strain divided faster by upregulating the expression of genes functioning in the cell cycle and downregulating genes involved in synthesis of amino acids, fatty acids, and sugars as well as the construction of ribosome and photosynthetic machinery. However, the relationship among the effected genes responsible for cell cycle, metabolism of fatty and amino acids, and construction of ribosome and photosynthetic machinery remained unclear. Further genetic studies are required for clarifying the genetic/metabolic networks underpinning the growth performance ofN. oceanica. These findings demonstrated that this mutation strategy was effective for improving the growth performance of this species and explored a means ofmicroalgal genetic improvement, particularly in species possessing a monoploid nucleus and asexual reproduction.展开更多
Oxytrichidae s. l. ciliates usually have 18 frontal-ventral-transverse cirri which are clustered to six distinct groups usu- ally originating from six longitudinal primordia segregating 1, 3, 3, 3, 4, 4 cirri. During ...Oxytrichidae s. l. ciliates usually have 18 frontal-ventral-transverse cirri which are clustered to six distinct groups usu- ally originating from six longitudinal primordia segregating 1, 3, 3, 3, 4, 4 cirri. During morphogenesis, three dorsal kinetics anlagen are primarily formed. Fragmentation of kinety 3 usually present, while sometimes secondarily lost. Dorsomarginal kineties are formed, while sometimes lost. Oxytrichids tend to have overlapping characters, e.g. cell shape and size, infraciliature, pellicle fea- tures. This makes a great problem for genera separation. In the present work, all typical 18 frontal-ventral-transverse-cirri Oxytrichi- dae s. 1. genera were revised systematically based on their living morphology, ciliature patterns and dorsal morphogenetic features. The outline of the genera, the schematic illustrations, and the key to typical 18 frontal-ventral-transverse-cirri genera of Oxytrichidae s. l. were clarified. Additionally, some morphological and morphogenetic patterns were summarized and compared.展开更多
Zeocin can cause double strand breaks of DNA and thus is frequently used as a selective antibiotic of eukaryotic Sh ble transformants. In non-transformation system, Zeocin may function as a mutagen if not totally leth...Zeocin can cause double strand breaks of DNA and thus is frequently used as a selective antibiotic of eukaryotic Sh ble transformants. In non-transformation system, Zeocin may function as a mutagen if not totally lethal. To verify such function of Zeocin, we mutated Nannochloropsis oceanica by increasing the concentration of Zeocin in medium gradually, and isolated a N. oceanica strain(single cell culture) which survived Zeocin up to 10.0μg mL^(-1). The Zeocin-tolerant strain entered the exponential growth phase later and grew slower than the wild strain. Transcriptome profiling showed that the Zeocin-tolerant N. oceanica strain survived Zeocin mainly by adapting(heritable), rather than acclimating(plastic) to Zeocin. Hence mutating N. oceanica with Zeocin was approved effective. Meanwhile, the physiological characteristics of this Zeocin-tolerant strain were demonstrated. As we proposed, N. oceanica tolerated Zeocin by strengthening its protein degradation and antioxidation. The genes controlling cell division and cellular response to stimuli may also have played important roles in the reduction of growth and the tolerance to Zeocin. Our findings evidenced that Zeocin can serve as an appropriate mutagen of microalgae. Creating variations through mutation with Zeocin may help to study the genetic basis of the traits of this monoploidy and asexual microalga, as well as improve its production.展开更多
A new record of Sebastes koreanus （Kim and Lee, 1994） was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Sample...A new record of Sebastes koreanus （Kim and Lee, 1994） was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics： light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded： dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I （CO1） gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research.展开更多
Meiofauna are fundamental components in mangrove ecosystem which play important roles in the energy flow and mat-ter cycling.In order to reveal the spatio-temporal distribution of meiofaunal assemblages in mangrove ha...Meiofauna are fundamental components in mangrove ecosystem which play important roles in the energy flow and mat-ter cycling.In order to reveal the spatio-temporal distribution of meiofaunal assemblages in mangrove habitats,sediment samples were collected in July(summer)and October(autumn)of 2013,January(winter)and April(spring)of 2014 in the mangrove tidal flat of Futian,Shenzhen,China.A total of 14 meiofaunal taxa were identified,including free-living marine nematodes,benthic copepods,polychaetes,oligochaetes,ostracods,isopods,etc.Additionally,there were also undetermined taxa.Results showed that the abun-dance range of meiofauna was(488.35±71.29)-(5136.36±623.38)ind(10 cm)−2.Marine nematodes were the most dominant group,with an average abundance of(1869.56±227.92)ind(10 cm)−2,accounting for 98.35%of the total abundance of meiofauna.The sea-sonal distribution of meiofauna showed that the abundance was the highest in summer,followed by those in spring,winter,and au-tumn.Vertical distribution showed that meiofauna were mainly distributed in the upper sediment layer(0-5 cm),with a proportion of 89.56%.Correlation analysis between meiofauna and environmental factors showed that meiofaunal abundance and biomass had significantly negative correlation with salinity.BIOENV analysis between meiofaunal assemblages and environmental factors show-ed that meiofaunal assemblages were affected by the combined effects of temperature,salinity,sediment median grain size,water content,and chlorophyll a content.展开更多
In this study, we compared the transcriptomes of Nannochloropsis oceanica cultured in f/2 medium prepared with seawater and freshwater, respectively, aiming to understand the acclimation mechanism of this alga to fres...In this study, we compared the transcriptomes of Nannochloropsis oceanica cultured in f/2 medium prepared with seawater and freshwater, respectively, aiming to understand the acclimation mechanism of this alga to freshwater. Differentially expressed genes were mainly assigned to the degradation of cell components, ion transportation, and ribosomal biogenesis. These find- ings indicate that the algal cells degrade its components （mainly amino acids and fatty acids） to yield excessive energy （ATP） to maintain cellular ion （mainly K＋ and Ca〉） homeostasis, while the depletion of amino acids and ATP, and the reduction of ribosomes attenuate the protein translation and finally slow down the cell growth.展开更多
文摘We determined the sequence of mitochondrial Cytochrome oxidase subunit I （CO1） in two Drosophila melanogaster strains originating at ＂Evolution Canyon＂, Israel. CO1 nucleotide sequences from two iso-female strains, 2-1 and 6-1, were 1,534 and 1,543 base-pairs, respectively. In each strain, ATAA was used in initiation of translation. Exchange rates for nucleotide and amino acid sequences were larger in the 6-1 strain than in the 2-1 strain when Oregon-R was used as the standard. Non-synonymous exchange rate was larger than synonymous exchange rate among the three strains.
基金Supported by the National Natural Science Foundation of China(No.31600325)the Self-determined Research Funds of the Central China Normal University(CCNU)from the Colleges’Basic Research and Operation of MOE(No.CCNU20TS022)。
文摘To assess the population development of submerged plant species in disturbed lake ecosystems,we need to better understand the genetic diversity and spatial genetic structure at a fine scale,as well as the impact of disturbances on the populations.Caohai Lake,in southwest China,is a suitable natural sampling lake because of its abundance of submerged plants and the intense human disturbance.Three widely distributed species,Potamogeton lucens,Ceratophyllum demersum,and Myriophyllum spicatum,were sampled;the spatial position of each individual was recorded in two-dimensional coordinates;and the species were analyzed genetically using microsatellite markers.Among the species studied,M.spicatum exhibited the highest genetic and clonal diversities.All P.lucens subpopulations but one showed a significant fine-scale spatial genetic structure(FSGS),which may result from the limited gene dispersal.However,M.spicatum and C.demersum,with a relatively large distance of gene dispersal,had no significant FSGS.The FSGS pattern of P.lucens at the dock site with intense boat disturbance was significantly different from that at other sites.Our results imply that the FSGS of submerged plants is affected by many factors including seed dispersal,vegetative reproduction and disturbance from birds and boats.Most subpopulations of the three species hadσ_(sex)^(2)/σ_(veg)^(2)values greater than one,implying that the sexual dispersal contributes more than vegetative dispersal to total gene dispersal.Therefore,it is worth paying attention to the importance of seed dispersal for population development of submerged plants in lake ecosystems.
基金The National Natural Science Foundation of China under contact No.32270434.
文摘All vertebrates have a definitive thyroid gland,or thyroid for short.As a critical organ for growth,development and metabolism,its origin and evolution have long received attention.On the basis of anatomical position,endodermal origination and histological features,the endostyle of amphioxus has been proposed as a homologue to the thyroid of vertebrates.This homology is further supported by the findings that the amphioxus endostyle abounds in thyroid hormones,possesses several thyroid-specific proteins such as thyroperoxidase,nicotinamide adenine dinucleotide phosphate(NADPH)oxidase and thyroglobulin,and expresses the thyroid-related transcription factors involved in the regulation of development of the vertebrate thyroid,including Nkx2.1,FoxE4 and Pax2/5/8.Importantly,our study on functionality,together with others,indicates significant similarities between the amphioxus endostyle and the vertebrate thyroid gland.Moreover,we show that the production of thyroid hormones by the amphioxus endostyle is mediated in a fashion similar to that of the vertebrate thyroid.These provide solid evidences that the amphioxus endostyle is the homologue of the vertebrate thyroid.From a phylogenetic viewpoint,we propose that the hypobranchial ridge,or endostyle-like structure,of hemichordates is the most primitive forerunner of the thyroid,from which the vertebrate thyroid is formed through the transformation of non-follicular endostyle of amphioxus to follicular endocrine organ of vertebrates.We also raise a couple of questions that demand further study.
基金supported by the National Key Research and Development Program of China(No.2022YFC2807500)Laoshan Laboratory(No.LSKJ202203201)+1 种基金the National Natural Science Foundation of China(Nos.42206147,42120104006 and 42176111)the Natural Science Foundation of Shandong Province(Nos.ZR2022QD046,ZR2021QD051).
文摘Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability of surrounding microbiomes have still not been de-termined.Here,the prokaryotic microbial community network stability and assembly char-acteristics were systematically analyzed and compared between the green tide and non-green tide periods.U.prolifera blooms weaken the community complexity and robustness of surrounding microbiomes,increasing fragmentation and decreasing diversity.Bacteria and archaea exhibited distinct community distributions and assembly patterns under the influ-ence of green tides,and bacterial communities were more sensitive to outbreaks of green tides.The bacterial communities exhibited a greater niche breadth and a lower phyloge-netic distance during the occurrence of U.prolifera green tides compared to those during the non-green tide period while archaeal communities remained unchanged,suggesting that the bacterial communities underwent stronger homogeneous selection and more sensitive to green tide blooms than the archaeal communities.Piecewise structural equation model analysis revealed that the different responses of major prokaryotic microbial groups,such as Cyanobacteria,to environmental variables during green tides,were influenced by the variations in pH and nitrate during green tides and correlated with the salinity gradient during the non-green tide period.This study elucidates the response of the adaptability,associations,and stability of surrounding microbiomes to outbreaks of U.prolifera green tides.
基金Supported by the National Key R&D Program of China(No.2022YFF1102300)the Key R&D Program of Shandong Province,China(No.2022LZGC004)+2 种基金the National Natural Science Foundation of China(No.32102757)the Science&Technology Innovation Project of Laoshan Laboratory(No.LSKJ202203205)the Fundamental Research Funds for the Central Universities(No.202262001)。
文摘Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in humans.Previous studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusion and size of lipid droplets.Nannochloropsis oceanica is a model oleaginous microalga with the accumulation potential of fatty acids.We believe that the SEIPIN homolog if any in N.oceanica should function as it does in humans,plant among others.In this study,we identified a homologous gene of SEIPIN in N.oceanica,constructed a bacterial plasmid containing the elements controlling the transcription of its complete antisense RNA,and integrated the linearized plasmid into the N.oceanica genome.We obtained a transformant in which the abundance of SEIPIN transcript is significantly down-regulated.Flow cytometry analysis showed that the triacylglycerol(TAG)content of the transformant is significantly lower than that of the wild type(WT).Transcriptomic analysis showed that the down-regulation of SEIPIN transcript abundance could affect the protein functioning in endoplasmic reticulum(ER),implying that SEIPIN gene can function in N.oceanica in a similar way to that in A.thaliana.
基金the National Natural Science Foundation of China(Nos.42188102,42120104006,41976117,42176111)the Fundamental Research Funds for the Central Universities(Nos.202172002,201812002)the funding from Andrew Mc Minn。
文摘Pseudoalteromonas is a group of marine bacteria widespread in diverse marine sediments,producing a wide range of bioactive compounds.However,only a limited number of Pseudoalteromonas phages have been isolated and studied.In this study,a novel lytic Pseudoalteromonas phage,denoted as vB_PalP_Y7,was isolated from sewage samples collected at the Seafood Market in Qingdao,China.vB_PalP_Y7 remained stable across a wide range of temperatures(-20–50℃)and a wide pH range(3–12).The vB_PalP_Y7 phage harbors a linear double-stranded DNA molecule of 57699 base pairs(bp)with a G+C content of 45.90%.Furthermore,it is predicted to contain 58 open reading frames(ORFs).Phylogenetic analysis and protein network relationship analysis revealed low similarity between vB_PalP_Y7 and viruses in the ICTV and IMG/VR4 database,suggesting that vB_PalP_Y7 may be a potential new genus,Miuvirus.This study contributed valuable insights to comprehend the relationship between Pseudoalteromonas phages and their host organisms.
基金Supported by the Public Science and Technology Research Funds Projects of Ocean(Nos.201305030,2013418043)
文摘A new record of Platycephalus sp.1 （sensu Nakabo, 2002） was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp. 1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit （COI） gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp. 1 was 0.1%. Net evolutionary distances between Platycephalus sp. 1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COl sequence analysis strongly supports the validity ofPlatyceohalus sp. 1 at genetic level.
基金the Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (No. 2011T1Z16)Israeli Ministry of Absorption for financial support of this research
文摘Biological soil crusts are essential components of arid ecosystems. We examined the variations in microfungal communities inhabiting different biological crust types in the vicinity of the Shapotou Research Station in the Tengger Desert, China. A total of 134 species from 66 genera were isolated using the soil dilution plate method. The mycobiota of the crusts from the Tengger Desert, similar to that of the Negev Desert in Israel, was dominated by melanin-containing species with large multicellular spores. Abundance of these xeric species increased spatially with increasing xeric conditions from moss-dominated to cyanobacterial crusts. Density of microfungal isolates displayed the opposite trend and was positively correlated with chlorophyll content, indicating the possible significant influence of organic matter content and wetness duration on fungal biomass. Within a chronosequence of the localities of different periods after sand stabilization with revegetation, little variations were revealed in species composition and isolate density of the crust microfungal communities, while a tendency towards a decrease in the community diversity level with the crust age was noted Microfungal communities from stabilized localities differed from those of the natural localities in abundance of the dominant and some frequent species, and in the fluctuations of diversity characteristics between the cyanobacterial and moss-dominated crusts. The variations in mycobiotie parameters in the soil crusts of the Tengger Desert were apparently associated with the topographically induced variations in abiotic conditions, while the differences in microfungal community of soil crusts between the Tengger and Negev deserts, such as the significantly higher abundance of thermotolerant species in the crusts of the Tengger Deserts, were caused by the principal differences in their precipitation regimes, associated with different rainy seasons, winter and summer in the Negev and Tengger deserts, respectively.
基金Supported by the Fundamental Research Funds for the Central Universities(No.201822022)the Key Development Plan of Shandong Province(No.2016GSF115014)
文摘Octopus minor is widely distributed along the northern coast of China. To date, there is little information on the prey selection process of this species. To understand this process, several experiments were carried out. Three types of bivalves, namely, Ruditapes philippinarum , Mactra chinensis , and Mytilus galloprovincialis , were used to observe the prey selection of O . minor and to analyze the potential causes of prey selection from three aspects: prey profi tability, adductor muscle tension and handling time. Under single-prey conditions, we found that the average (±SD) predation rates of O . minor on R . philippinarum , M . chinensis , and M . galloprovincialis were 1.73±0.50, 1.27±0.42, and 0.8±0.2/d, respectively. Under diff erent prey combinations, octopods actively selected one type of prey over the other(s), and the order of prey preference was R . philippinarum , followed by M . chinensis and lastly M. galloprovincialis . Furthermore, the shells of the consumed prey showed that O . minor only consumed bivalves by pulling them apart since there was no evidence of drill holes on the shells. The prey selection of O . minor was related to the prey profi tability and handling time;O . minor appeared to select preys with a higher profi tability and a shorter handling time. However, the diffi culty in opening the bivalve was not consistent with the prey preference of the octopods. These results suggest that O . minor prefers to consume R . philippinarum possibly due to a high profi tability and a short handling time that supports the optimum Foraging Theory.
文摘Diabetes mellitus(DM) is the third most common noninfectious disease leading to early disability and high mortality. Moreover, the number of patients is growing every year. The main symptom of DM is hyperglycemia. Increased levels of blood glucose activate polyol, hexosamine, and protein kinase metabolic pathways cause the intensification of non-enzymatic glycosylation and nitration of macromolecules. This, in turn, leads to the development of oxidative and nitrative stresses and secondary complications, such as different kinds of microand macroangiopathies. Metabolic disorders caused by insulin deficiency in diabetes significantly impede the functioning of a homeostasis system, which change the physical, biochemical, morphological, and functional properties of blood cells. As a result, the oxygen-transport function of red blood cells(RBCs), rheological properties of the blood, and functions of immunocompetent cells as well as the process of apoptosis are primarily affected. Modern pharmacotherapy focuses on the search for new preparations that aim to decrease blood glucose levels. Undesirable side effects and adverse reactions caused by synthetic medicines led to the search and investigation of new preparations of natural origin. Medicinal mushrooms play an important role among such new preparations. They are a source of a large number of high-and lowmolecular compounds with pronounced biological effects. Our investigations show pronounced hypoglycemic and anti-anemic action of submerged cultivated mycelium powder of medicinal mushrooms Agaricus brasiliensis(A. brasiliensis) and Ganoderma lucidum(G. lucidum) on streptozotocin-induced DM in rats. Also, we showed that mycelium powders have membrane protective properties as evidenced by the redistribution of RBC populations towards the growth of full functional cell numbers. Normalization of parameters of leukocyte formula and suppression of apoptosis of white blood cells in diabeticrats treated with A. brasiliensis and G. lucidum mycelia indicates pronounced positive effects of these strains of mushrooms. Thus, the use of medicinal mushrooms for treatment of DM and in prevention development of its secondary complications might be a new effective approach of this disease's cure. This article is aimed at summarizing and analyzing the literature data and basic achievements concerning DM type 1 treatment using medicinal mushrooms and showing the results obtained in our research.
基金Supported by the Natural Science Foundation of China (No. 40906065)the China Postdoctoral Science Foundation (No. 20090451351)a grant from the Center of Excellence in Biodiversity, King Saud University
文摘We documented the pattern of cell development in Euplotes charon. The ontogenesis of this species was similar to many of its congeners, except for the formation of the caudal cirri. In E. Charon, a caudal cirrus is formed posterior to each of the rightmost two or three dorsal kinety anlage in the proter, and the second rightmost dorsal kinety in the opisthe. In addition, two caudal cirri are formed posterior to the rightmost dorsal kinety in the opisthe. This pattern of development represents a completely new type. Based on our evaluation, and in comparison with previous studies, we also conclude that the pattern of cell development is variable among species in the Euplotes genera. The variation is particularly evident during the formation of frontoventral and caudal cirri. Based on the segmentation pattern of frontal-midventral transverse cirral anlagen, cirri reduction, and migration of frontoventral cirri, we identified five types: the affinis-type, the eurystomus-type, the charon-type, the raikovi-type and orientalis-type. Euplotes (s. l.) can also be divided into three types based on the formation of caudal cirri: focardii-type, vannus-type and charon-type. Indeed, we conclude that the number (one or two) of marginal cirri should be given as much consideration as the genetic separation. Given this, we reassessed the validity of using genetic separation to classify the group. Generally, the morphogenetic data disagreed with the molecular data (SSrRNA gene sequences). Given these discrepancies, it is too early to draw conclusions on the systematic arrangement of this species-rich taxon.
基金Supported by the National Natural Science Foundation of China(No.31270408)the National High Technology Research and Development Program of China(863 Program)(No.2014AA022001)
文摘Nannochloropsis oceanica promises to be an industrial-level producer of polyunsaturated fatty acids. In this study, the fastest and slowest growing N. oceanica mutants were selected through N-methyl-N＇-nitro-N-nitrosoguanidine mutation, and two mutant strains and the wild type （WT） subjected to transcriptome profiling. It was found that the 0D680 reads at stationary growth phase of both WT and its mutants were proportional to their cell density, thus indicating their division rate and growth speed during culture. This chemical mutation was effective for improving growth performance, and the fast strain divided faster by upregulating the expression of genes functioning in the cell cycle and downregulating genes involved in synthesis of amino acids, fatty acids, and sugars as well as the construction of ribosome and photosynthetic machinery. However, the relationship among the effected genes responsible for cell cycle, metabolism of fatty and amino acids, and construction of ribosome and photosynthetic machinery remained unclear. Further genetic studies are required for clarifying the genetic/metabolic networks underpinning the growth performance ofN. oceanica. These findings demonstrated that this mutation strategy was effective for improving the growth performance of this species and explored a means ofmicroalgal genetic improvement, particularly in species possessing a monoploid nucleus and asexual reproduction.
基金supported by the National Natural Science Foundation of China (31372148)the Fundamental Research Funds for the Central Universities
文摘Oxytrichidae s. l. ciliates usually have 18 frontal-ventral-transverse cirri which are clustered to six distinct groups usu- ally originating from six longitudinal primordia segregating 1, 3, 3, 3, 4, 4 cirri. During morphogenesis, three dorsal kinetics anlagen are primarily formed. Fragmentation of kinety 3 usually present, while sometimes secondarily lost. Dorsomarginal kineties are formed, while sometimes lost. Oxytrichids tend to have overlapping characters, e.g. cell shape and size, infraciliature, pellicle fea- tures. This makes a great problem for genera separation. In the present work, all typical 18 frontal-ventral-transverse-cirri Oxytrichi- dae s. 1. genera were revised systematically based on their living morphology, ciliature patterns and dorsal morphogenetic features. The outline of the genera, the schematic illustrations, and the key to typical 18 frontal-ventral-transverse-cirri genera of Oxytrichidae s. l. were clarified. Additionally, some morphological and morphogenetic patterns were summarized and compared.
基金funded by the National Natural Science Foundation of China (No. 31270408)National High Technology Research and Development Program (863 Program) of China (No. 2014AA022001)
文摘Zeocin can cause double strand breaks of DNA and thus is frequently used as a selective antibiotic of eukaryotic Sh ble transformants. In non-transformation system, Zeocin may function as a mutagen if not totally lethal. To verify such function of Zeocin, we mutated Nannochloropsis oceanica by increasing the concentration of Zeocin in medium gradually, and isolated a N. oceanica strain(single cell culture) which survived Zeocin up to 10.0μg mL^(-1). The Zeocin-tolerant strain entered the exponential growth phase later and grew slower than the wild strain. Transcriptome profiling showed that the Zeocin-tolerant N. oceanica strain survived Zeocin mainly by adapting(heritable), rather than acclimating(plastic) to Zeocin. Hence mutating N. oceanica with Zeocin was approved effective. Meanwhile, the physiological characteristics of this Zeocin-tolerant strain were demonstrated. As we proposed, N. oceanica tolerated Zeocin by strengthening its protein degradation and antioxidation. The genes controlling cell division and cellular response to stimuli may also have played important roles in the reduction of growth and the tolerance to Zeocin. Our findings evidenced that Zeocin can serve as an appropriate mutagen of microalgae. Creating variations through mutation with Zeocin may help to study the genetic basis of the traits of this monoploidy and asexual microalga, as well as improve its production.
基金Supported by the National Natural Science Foundation of China(No.41176117)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20120132110009)
文摘A new record of Sebastes koreanus （Kim and Lee, 1994） was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics： light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded： dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I （CO1） gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research.
基金jointly supported by the Fundamental Research Funds for the Central Universities (Nos. 201964 024 and 201362018)the Biodiversity Investigation, Observation and Assessment Program (2019 – 2023) of Ministry of Ecology and Environment of China
文摘Meiofauna are fundamental components in mangrove ecosystem which play important roles in the energy flow and mat-ter cycling.In order to reveal the spatio-temporal distribution of meiofaunal assemblages in mangrove habitats,sediment samples were collected in July(summer)and October(autumn)of 2013,January(winter)and April(spring)of 2014 in the mangrove tidal flat of Futian,Shenzhen,China.A total of 14 meiofaunal taxa were identified,including free-living marine nematodes,benthic copepods,polychaetes,oligochaetes,ostracods,isopods,etc.Additionally,there were also undetermined taxa.Results showed that the abun-dance range of meiofauna was(488.35±71.29)-(5136.36±623.38)ind(10 cm)−2.Marine nematodes were the most dominant group,with an average abundance of(1869.56±227.92)ind(10 cm)−2,accounting for 98.35%of the total abundance of meiofauna.The sea-sonal distribution of meiofauna showed that the abundance was the highest in summer,followed by those in spring,winter,and au-tumn.Vertical distribution showed that meiofauna were mainly distributed in the upper sediment layer(0-5 cm),with a proportion of 89.56%.Correlation analysis between meiofauna and environmental factors showed that meiofaunal abundance and biomass had significantly negative correlation with salinity.BIOENV analysis between meiofaunal assemblages and environmental factors show-ed that meiofaunal assemblages were affected by the combined effects of temperature,salinity,sediment median grain size,water content,and chlorophyll a content.
基金financially supported by the National Natural Science Foundation of China(31270408)National High Technology Research and Development Program(863 Program)of China(2014AA022001)
文摘In this study, we compared the transcriptomes of Nannochloropsis oceanica cultured in f/2 medium prepared with seawater and freshwater, respectively, aiming to understand the acclimation mechanism of this alga to freshwater. Differentially expressed genes were mainly assigned to the degradation of cell components, ion transportation, and ribosomal biogenesis. These find- ings indicate that the algal cells degrade its components （mainly amino acids and fatty acids） to yield excessive energy （ATP） to maintain cellular ion （mainly K＋ and Ca〉） homeostasis, while the depletion of amino acids and ATP, and the reduction of ribosomes attenuate the protein translation and finally slow down the cell growth.
