The giant spiny frog （Quasipaa spinosa） is an endangered species with a relatively small distribution limited to southern China and Northern Vietnam. This species is becoming increasingly threatened because of over-...The giant spiny frog （Quasipaa spinosa） is an endangered species with a relatively small distribution limited to southern China and Northern Vietnam. This species is becoming increasingly threatened because of over-exploitation and habitat degradation. This study provides data on the genetic diversity and population genetic structure of the giant spiny frog to facilitate the further development of effective conservation recommendations for this economically important but threatened species. We examined 10 species-specific microsatellite loci and Cyt b genes （562 bp） collected from 13 wild populations across the entire range of this species. Results of 10 microsatellite loci analysis showed a generally high level of genetic diversity. Moreover, the genetic differentiation among all 12 populations was moderate to large （overall Fs7= 0.1057）. A total of 51 haplotypes were identified for Cyt b, which suggests high haplotype nucleotide diversities. Phylogeographic and population structure analyses using both DNA markers suggested that the wild giant spiny frog can be divided into four distinct major clades, i.e., Northern Vietnam, Western China, Central China, and Eastern China. The clades with significant genetic divergence are reproductively isolated, as evidenced by a high number of private alleles and strong incidence of failed amplification in microsatellite loci. Our research, coupled with other studies, suggests that Q. spinosa might be a species complex within which no detectable morphological variation has been revealed. The four phylogenetic clades and some subclades with distinct geographical distribution should be regarded as independent management units for conservation purposes.展开更多
Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are wi...Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.展开更多
Medium spiny neurons(MSNs)in the striatum,which can be divided into D1 and D2 MSNs,originate from the lateral ganglionic eminence(LGE).Previously,we reported that Six3 is a downstream target of Sp8/Sp9 in the transcri...Medium spiny neurons(MSNs)in the striatum,which can be divided into D1 and D2 MSNs,originate from the lateral ganglionic eminence(LGE).Previously,we reported that Six3 is a downstream target of Sp8/Sp9 in the transcriptional regulatory cascade of D2 MSN development and that conditionally knocking out Six3 leads to a severe loss of D2 MSNs.Here,we showed that Six3 mainly functions in D2 MSN precursor cells and gradually loses its function as D2 MSNs mature.Conditional deletion of Six3 had little effect on cell proliferation but blocked the differentiation of D2 MSN precursor cells.In addition,conditional overexpression of Six3 promoted the differentiation of precursor cells in the LGE.We measured an increase of apoptosis in the postnatal striatum of conditional Six3-knockout mice.This suggests that,in the absence of Six3,abnormally differentiated D2 MSNs are eliminated by programmed cell death.These results further identify Six3 as an important regulatory element during D2 MSN differentiation.展开更多
During brain ischemia,excitotoxicity and peri-infarct depolarization injuries occur and cause cerebral tissue damage.Indeed,anoxic depolarization,consisting of massive neuronal depolarization due to the loss of membra...During brain ischemia,excitotoxicity and peri-infarct depolarization injuries occur and cause cerebral tissue damage.Indeed,anoxic depolarization,consisting of massive neuronal depolarization due to the loss of membrane ion gradients,occurs in vivo or in vitro during an energy failure.The neuromodulator adenosine is released in huge amounts during cerebral ischemia and exerts its effects by activating specific metabotropic receptors,namely:A_(1),A_(2A),A_(2B),and A_(3).The A_(2A)receptor subtype is highly expressed in striatal medium spiny neurons,which are particularly susceptible to ischemic damage.Evidence indicates that the A2Areceptors are upregulated in the rat striatum after stroke and the selective antagonist SCH58261 protects from exaggerated glutamate release within the first 4 hours from the insult and alleviates neurological impairment and histological injury in the following 24 hours.We recently added new knowledge to the mechanisms by which the adenosine A2Areceptor subtype participates in ischemia-induced neuronal death by performing patch-clamp recordings from medium spiny neurons in rat striatal brain slices exposed to oxygen and glucose deprivation.We demonstrated that the selective block of A2Areceptors by SCH58261 significantly reduced ionic imbalance and delayed the anoxic depolarization in medium spiny neurons during oxygen and glucose deprivation and that the mechanism involves voltage-gated K+channel modulation and a presynaptic inhibition of glutamate release by the A2Areceptor antagonist.The present review summarizes the latest findings in the literature about the possibility of developing selective ligands of A2Areceptors as advantageous therapeutic tools that may contribute to counteracting neurodegeneration after brain ischemia.展开更多
The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, ...The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, 2008). Most cells in the striatum are GABAergic, including a large population (90%-95%) of medium spiny neurons (MSNs) and a small population of interneurons.展开更多
To investigate the characters of repetitive DNA sequence in the sex chromosomes of the spiny eel （Mastacembelus aculeatus）, the X chromosomal library was screened and a family of repetitive sequence, consisting of M...To investigate the characters of repetitive DNA sequence in the sex chromosomes of the spiny eel （Mastacembelus aculeatus）, the X chromosomal library was screened and a family of repetitive sequence, consisting of Ma 1-Ma 6, was isolated. The fluorescence in situ hybridization （FISH） result confirmed that Ma 1- Ma 5 dispersed over sex chromosomes and all autosomes, whereas, Ma 6 is sex chromosome-specific and distributed only on the C-band positive regions of X chromosome, and Ma 6 maybe the main components of the heterochromatic regions of X chromosome. This study provides additional information about the evolution of sex chromosomes in lower vertebrates such as fish.展开更多
Autapses selectively form in specific cell types in many brain regions.Previous studies have also found putative autapses in principal spiny projection neurons(SPNs)in the striatum.However,it remains unclear whether t...Autapses selectively form in specific cell types in many brain regions.Previous studies have also found putative autapses in principal spiny projection neurons(SPNs)in the striatum.However,it remains unclear whether these neurons indeed form physiologically functional autapses.We applied whole-cell recording in striatal slices and identified autaptic cells by the occurrence of prolonged asynchronous release(AR)of neurotransmitters after bursts of high-frequency action potentials(APs).Surprisingly,we found no autaptic AR in SPNs,even in the presence of Sr^(2+).However,robust autaptic AR was recorded in parvalbumin(PV)-expressing neurons.The autaptic responses were mediated by GABA_(A) receptors and their strength was dependent on AP frequency and number.Further computer simulations suggest that autapses regulate spiking activity in PV cells by providing self-inhibition and thus shape network oscillations.Together,our results indicate that PV neurons,but not SPNs,form functional autapses,which may play important roles in striatal functions.展开更多
Dear Editor,African spiny mouse, Acomys dimidiatus, is a mammalian model for regeneration studies because of its ability to functionally regenerate several tissues. As limited regenerative abilities in mammals are vie...Dear Editor,African spiny mouse, Acomys dimidiatus, is a mammalian model for regeneration studies because of its ability to functionally regenerate several tissues. As limited regenerative abilities in mammals are viewed as an antitumor strategy, it is intriguing how Acomys balances regeneration and tumor suppression. In this study, we investigated if Acomys is susceptible to carcinogenesis. We report that, like in mice, two oncogenic hits-activation of oncogenic Ras^(G12V) and inactivation of p53 or p Rb-are sufficient to malignantly transform skin fibroblasts from Acomys.展开更多
The common spiny mouse(Acomys cahirinus)inhibits the foraging activity of the golden spiny mouse(A.russatus).These two sympatric species of spiny mice,which are considered habitat competitors,occur in extreme arid env...The common spiny mouse(Acomys cahirinus)inhibits the foraging activity of the golden spiny mouse(A.russatus).These two sympatric species of spiny mice,which are considered habitat competitors,occur in extreme arid environments.To test this theory of competition,the influence of urinary odors of both conspecific and heterospecific mice on the foraging behavior of A.russatus was studied under controlled laboratory conditions.Twenty adult males,born in captivity and unfamiliar to the odors of the donor mice,were tested in 3 experimental conditions choosing between 2 seed patches that were scented with urine of either heterospecifics(A.cahirinus),conspecifics(A.russatus)or controls(odors of the tested individual).Of the 20 males,12 were also tested with urine of unfamiliar gerbils,bushy-tailed jird,considered as competitors in the field.Both conspecific and heterospecific urine samples from Acomys significantly reduced foraging behavior of A.russatus when compared to the control odor.The inhibitory effect of the Acomys urine does not result from the novelty of chemical stimuli of the urine because no effect was shown with unfamiliar gerbil urine.The findings are in accordance with the general theory that A.cahirinus dominates the foraging activity of A.russatus.We hypothesize that chemical cues in the urine of Acomys spp.might induce a negative effect on the foraging behavior of A.russatus.展开更多
We herein describe a new species of spiny frog,Quasipaa yunkaiensis sp.nov.from Yunkaishan National Nature Reserve,Xinyi City,Guangdong Province,China.Morphological examination combined with mitochondrial(810 bp Cyt b...We herein describe a new species of spiny frog,Quasipaa yunkaiensis sp.nov.from Yunkaishan National Nature Reserve,Xinyi City,Guangdong Province,China.Morphological examination combined with mitochondrial(810 bp Cyt b)and nuclear(1852 bp concatenated Rag2,Tyr,and Rhod)genetic data was used to test its distinctiveness within Quasipaa.Morphologically,the new species differs from other congeners by the following diagnostic characteristics:relatively large body size within Quasipaa;dorsal skin relatively smooth,having sparse tubercles;lacking spiny tubercles on the ventrolateral sides of the body;lacking keratinized spines in the ventral surface of the body,only present on prepollex,fingers I and II,in breeding males.Both mitochondrial and nuclear phylogenetic results indicate that Quasipaa yunkaiensis sp.nov.constitutes a highly supported,deeply divergent lineage,but its precise phylogenetic placement within the genus Quasipaa remains unresolved.In view of the pronounced discordance between mitochondrial and nuclear datasets within Quasipaa,we encourage future studies to use genome-wide data to improve phylogenetic resolution and to estimate species diversity more accurately.展开更多
γ-Aminobutyric acid（GABA）,plays a key role in all stages of life,also is considered the main inhibitory neurotransmitter.GABA activates two kind of membrane receptors known as GABAA and GABAB,the first one is respo...γ-Aminobutyric acid（GABA）,plays a key role in all stages of life,also is considered the main inhibitory neurotransmitter.GABA activates two kind of membrane receptors known as GABAA and GABAB,the first one is responsible to render tonic inhibition by pentameric receptors containing α4-6,β3,δ,or ρ1-3 subunits,they are located at perisynaptic and/or in extrasynaptic regions.The biophysical properties of GABAA tonic inhibition have been related with cellular protection against excitotoxic injury and cell death in presence of excessive excitation.On this basis,GABAA tonic inhibition has been proposed as a potential target for therapeutic intervention of Huntington＇s disease.Huntington＇s disease is a neurodegenerative disorder caused by a genetic mutation of the huntingtin protein.For experimental studies of Huntington＇s disease mouse models have been developed,such as R6/1,R6/2,Hdh Q92,Hdh Q150,as well as YAC128.In all of them,some key experimental reports are focused on neostriatum.The neostriatum is considered as the most important connection between cerebral cortex and basal ganglia structures,its cytology display two pathways called direct and indirect constituted by medium sized spiny neurons expressing dopamine D1 and D2 receptors respectively,they display strong expression of many types of GABAA receptors,including tonic subunits.The studies about of GABAA tonic subunits and Huntington＇s disease into the neostriatum are rising in recent years,suggesting interesting changes in their expression and localization which can be used as a strategy to delay the cellular damage caused by the imbalance between excitation and inhibition,a hallmark of Huntington＇s disease.展开更多
基金supported by the National Science Foundation of China(No.31172116 and No.31472015)the Major Science and Technology Specific Projects of Zhejiang Province of China(No.2010C12008)+2 种基金the project of the Science Technology Commission of Zhejiang Province of China(No.2011C22006)the Found for the science and technology innovation team of Zhejiang Province of China(No.2012R10026-07)the Key Program of the Twelfth Five Year New Aquatic Varieties Breeding Cooperation of Zhejiang Province of China(2012C12907-9)
文摘The giant spiny frog （Quasipaa spinosa） is an endangered species with a relatively small distribution limited to southern China and Northern Vietnam. This species is becoming increasingly threatened because of over-exploitation and habitat degradation. This study provides data on the genetic diversity and population genetic structure of the giant spiny frog to facilitate the further development of effective conservation recommendations for this economically important but threatened species. We examined 10 species-specific microsatellite loci and Cyt b genes （562 bp） collected from 13 wild populations across the entire range of this species. Results of 10 microsatellite loci analysis showed a generally high level of genetic diversity. Moreover, the genetic differentiation among all 12 populations was moderate to large （overall Fs7= 0.1057）. A total of 51 haplotypes were identified for Cyt b, which suggests high haplotype nucleotide diversities. Phylogeographic and population structure analyses using both DNA markers suggested that the wild giant spiny frog can be divided into four distinct major clades, i.e., Northern Vietnam, Western China, Central China, and Eastern China. The clades with significant genetic divergence are reproductively isolated, as evidenced by a high number of private alleles and strong incidence of failed amplification in microsatellite loci. Our research, coupled with other studies, suggests that Q. spinosa might be a species complex within which no detectable morphological variation has been revealed. The four phylogenetic clades and some subclades with distinct geographical distribution should be regarded as independent management units for conservation purposes.
基金supported by the National Natural Science Foundation of China(51973157,61904123,52103061,52203066)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(2018KJ196)+3 种基金the project funded by China Postdoctoral Science Foundation(2021T140419)Tianjin Municipal College Student’Innovation and Entrepreneurship Training Program(202110058052)the National Innovation and Entrepreneurship Training Program for College Students(202110058017)the State Key Laboratory of Membrane and Membrane Separation,Tiangong University。
文摘Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.
基金the National Key Research and Development Program of China(2018YFAO 108000)the National Natural Science Foundation of China(31630032,81974175,and 31820103006)the Shanghai Municipal Science and Technology Major Project(2018SHZDZX01).
文摘Medium spiny neurons(MSNs)in the striatum,which can be divided into D1 and D2 MSNs,originate from the lateral ganglionic eminence(LGE).Previously,we reported that Six3 is a downstream target of Sp8/Sp9 in the transcriptional regulatory cascade of D2 MSN development and that conditionally knocking out Six3 leads to a severe loss of D2 MSNs.Here,we showed that Six3 mainly functions in D2 MSN precursor cells and gradually loses its function as D2 MSNs mature.Conditional deletion of Six3 had little effect on cell proliferation but blocked the differentiation of D2 MSN precursor cells.In addition,conditional overexpression of Six3 promoted the differentiation of precursor cells in the LGE.We measured an increase of apoptosis in the postnatal striatum of conditional Six3-knockout mice.This suggests that,in the absence of Six3,abnormally differentiated D2 MSNs are eliminated by programmed cell death.These results further identify Six3 as an important regulatory element during D2 MSN differentiation.
基金supported by University of Florence RICATEN 2023 to EC.Grant/Award Numbers 58514_InternazionalizzazioneUniversity of Florence,to EC.Parkinson’s UK,Grant/Award Number:H-0902 to AJGWellcome Trust,Grant/Award Number:0926/Z/10/Z to AJG。
文摘During brain ischemia,excitotoxicity and peri-infarct depolarization injuries occur and cause cerebral tissue damage.Indeed,anoxic depolarization,consisting of massive neuronal depolarization due to the loss of membrane ion gradients,occurs in vivo or in vitro during an energy failure.The neuromodulator adenosine is released in huge amounts during cerebral ischemia and exerts its effects by activating specific metabotropic receptors,namely:A_(1),A_(2A),A_(2B),and A_(3).The A_(2A)receptor subtype is highly expressed in striatal medium spiny neurons,which are particularly susceptible to ischemic damage.Evidence indicates that the A2Areceptors are upregulated in the rat striatum after stroke and the selective antagonist SCH58261 protects from exaggerated glutamate release within the first 4 hours from the insult and alleviates neurological impairment and histological injury in the following 24 hours.We recently added new knowledge to the mechanisms by which the adenosine A2Areceptor subtype participates in ischemia-induced neuronal death by performing patch-clamp recordings from medium spiny neurons in rat striatal brain slices exposed to oxygen and glucose deprivation.We demonstrated that the selective block of A2Areceptors by SCH58261 significantly reduced ionic imbalance and delayed the anoxic depolarization in medium spiny neurons during oxygen and glucose deprivation and that the mechanism involves voltage-gated K+channel modulation and a presynaptic inhibition of glutamate release by the A2Areceptor antagonist.The present review summarizes the latest findings in the literature about the possibility of developing selective ligands of A2Areceptors as advantageous therapeutic tools that may contribute to counteracting neurodegeneration after brain ischemia.
基金supported by grants from the National Key Research and Development Program of China (2016YFA0100702 and 2016YFC0902502)the National Natural Science Foundation of China (31670789 and 31671316)the CAMS Innovation Fund for Medical Sciences (CIFMS, 2016I2M-2-001, 2016-I2M-1-001, 2016-I2M-1-004 and 2017-I2M-1004)
文摘The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, 2008). Most cells in the striatum are GABAergic, including a large population (90%-95%) of medium spiny neurons (MSNs) and a small population of interneurons.
基金Supported by the National Natural Science Foundation of China(30400044)
文摘To investigate the characters of repetitive DNA sequence in the sex chromosomes of the spiny eel （Mastacembelus aculeatus）, the X chromosomal library was screened and a family of repetitive sequence, consisting of Ma 1-Ma 6, was isolated. The fluorescence in situ hybridization （FISH） result confirmed that Ma 1- Ma 5 dispersed over sex chromosomes and all autosomes, whereas, Ma 6 is sex chromosome-specific and distributed only on the C-band positive regions of X chromosome, and Ma 6 maybe the main components of the heterochromatic regions of X chromosome. This study provides additional information about the evolution of sex chromosomes in lower vertebrates such as fish.
基金supported by the National Natural Science Foundation of China(32130044,31630029,32171094,and 32100930)the National Key Research and Development Program of China(2021ZD0202500).
文摘Autapses selectively form in specific cell types in many brain regions.Previous studies have also found putative autapses in principal spiny projection neurons(SPNs)in the striatum.However,it remains unclear whether these neurons indeed form physiologically functional autapses.We applied whole-cell recording in striatal slices and identified autaptic cells by the occurrence of prolonged asynchronous release(AR)of neurotransmitters after bursts of high-frequency action potentials(APs).Surprisingly,we found no autaptic AR in SPNs,even in the presence of Sr^(2+).However,robust autaptic AR was recorded in parvalbumin(PV)-expressing neurons.The autaptic responses were mediated by GABA_(A) receptors and their strength was dependent on AP frequency and number.Further computer simulations suggest that autapses regulate spiking activity in PV cells by providing self-inhibition and thus shape network oscillations.Together,our results indicate that PV neurons,but not SPNs,form functional autapses,which may play important roles in striatal functions.
基金supported by grants from the US National Institute on Aging to V.G.and A.S.All institutional guidelines for the care and use of laboratory animals were followedAll animal experiments were approved and performed in accordance with guidelines set forth by the University of Rochester Committee on Animal Resources with protocol number 2017-033(mouse)and 2017-027(Acomys dimidiatus,African spiny mice)All authors have read and approved the manuscript for publication,The data,analytic methods,and study materials will be made available to other researchers for purposes of reproducing the results or replicating the procedure.The RNA-seq raw data and count tables have been deposited in GEO(GSE287010).
文摘Dear Editor,African spiny mouse, Acomys dimidiatus, is a mammalian model for regeneration studies because of its ability to functionally regenerate several tissues. As limited regenerative abilities in mammals are viewed as an antitumor strategy, it is intriguing how Acomys balances regeneration and tumor suppression. In this study, we investigated if Acomys is susceptible to carcinogenesis. We report that, like in mice, two oncogenic hits-activation of oncogenic Ras^(G12V) and inactivation of p53 or p Rb-are sufficient to malignantly transform skin fibroblasts from Acomys.
基金supported by the French‘Centre National de la Recherche Scientifique’(CNRS International Relationships Grants to Claude Baudoin in 1996 and 1998).
文摘The common spiny mouse(Acomys cahirinus)inhibits the foraging activity of the golden spiny mouse(A.russatus).These two sympatric species of spiny mice,which are considered habitat competitors,occur in extreme arid environments.To test this theory of competition,the influence of urinary odors of both conspecific and heterospecific mice on the foraging behavior of A.russatus was studied under controlled laboratory conditions.Twenty adult males,born in captivity and unfamiliar to the odors of the donor mice,were tested in 3 experimental conditions choosing between 2 seed patches that were scented with urine of either heterospecifics(A.cahirinus),conspecifics(A.russatus)or controls(odors of the tested individual).Of the 20 males,12 were also tested with urine of unfamiliar gerbils,bushy-tailed jird,considered as competitors in the field.Both conspecific and heterospecific urine samples from Acomys significantly reduced foraging behavior of A.russatus when compared to the control odor.The inhibitory effect of the Acomys urine does not result from the novelty of chemical stimuli of the urine because no effect was shown with unfamiliar gerbil urine.The findings are in accordance with the general theory that A.cahirinus dominates the foraging activity of A.russatus.We hypothesize that chemical cues in the urine of Acomys spp.might induce a negative effect on the foraging behavior of A.russatus.
基金supported by the DFGP Project of Fauna of Guangdong-202115,Science and Technology Planning Projects of Guangdong Province(2021B1212110002)the National Natural Science Foundation of China(32400361)+1 种基金Biological Resources Programme,Chinese Academy of Sciences(CAS-TAX-24-052)the project“Population Survey and Monitoring of the Shinisaurus crocodilurus and Syntopic Amphibian and Reptile Inventory”supported by the Guangdong Wildlife Rescue and Monitoring Center.
文摘We herein describe a new species of spiny frog,Quasipaa yunkaiensis sp.nov.from Yunkaishan National Nature Reserve,Xinyi City,Guangdong Province,China.Morphological examination combined with mitochondrial(810 bp Cyt b)and nuclear(1852 bp concatenated Rag2,Tyr,and Rhod)genetic data was used to test its distinctiveness within Quasipaa.Morphologically,the new species differs from other congeners by the following diagnostic characteristics:relatively large body size within Quasipaa;dorsal skin relatively smooth,having sparse tubercles;lacking spiny tubercles on the ventrolateral sides of the body;lacking keratinized spines in the ventral surface of the body,only present on prepollex,fingers I and II,in breeding males.Both mitochondrial and nuclear phylogenetic results indicate that Quasipaa yunkaiensis sp.nov.constitutes a highly supported,deeply divergent lineage,but its precise phylogenetic placement within the genus Quasipaa remains unresolved.In view of the pronounced discordance between mitochondrial and nuclear datasets within Quasipaa,we encourage future studies to use genome-wide data to improve phylogenetic resolution and to estimate species diversity more accurately.
基金the programs for the postdoctoral fellowships-Chilean CONICYT-FONDECYT#3140218,Mexican CONACYT#164978 and DID-UACh S-2015-81Sistema Nacional de Investigadores#58512 to Abraham Rosas-Arellano+2 种基金supported by USACH PhD fellowshipsupported with a PhD fellowship from CONACYT(#299627)FONDECYT grants 1151206 and 1110571 to Maite A.Castro
文摘γ-Aminobutyric acid（GABA）,plays a key role in all stages of life,also is considered the main inhibitory neurotransmitter.GABA activates two kind of membrane receptors known as GABAA and GABAB,the first one is responsible to render tonic inhibition by pentameric receptors containing α4-6,β3,δ,or ρ1-3 subunits,they are located at perisynaptic and/or in extrasynaptic regions.The biophysical properties of GABAA tonic inhibition have been related with cellular protection against excitotoxic injury and cell death in presence of excessive excitation.On this basis,GABAA tonic inhibition has been proposed as a potential target for therapeutic intervention of Huntington＇s disease.Huntington＇s disease is a neurodegenerative disorder caused by a genetic mutation of the huntingtin protein.For experimental studies of Huntington＇s disease mouse models have been developed,such as R6/1,R6/2,Hdh Q92,Hdh Q150,as well as YAC128.In all of them,some key experimental reports are focused on neostriatum.The neostriatum is considered as the most important connection between cerebral cortex and basal ganglia structures,its cytology display two pathways called direct and indirect constituted by medium sized spiny neurons expressing dopamine D1 and D2 receptors respectively,they display strong expression of many types of GABAA receptors,including tonic subunits.The studies about of GABAA tonic subunits and Huntington＇s disease into the neostriatum are rising in recent years,suggesting interesting changes in their expression and localization which can be used as a strategy to delay the cellular damage caused by the imbalance between excitation and inhibition,a hallmark of Huntington＇s disease.
