Hepatitis C virus(HCV) is a major human pathogen of chronic hepatitis and related liver diseases. Innate immunity is the first line of defense against invading foreign pathogens, and its activation is dependent on the...Hepatitis C virus(HCV) is a major human pathogen of chronic hepatitis and related liver diseases. Innate immunity is the first line of defense against invading foreign pathogens, and its activation is dependent on the recognition of these pathogens by several key sensors. The interferon(IFN) system plays an essential role in the restriction of HCV infection via the induction of hundreds of IFN-stimulated genes(ISGs) that inhibit viral replication and spread. However, numerous factors that trigger immune dysregulation, including viral factors and host genetic factors, can help HCV to escape host immune response, facilitating viral persistence. In this review, we aim to summarize recent advances in understanding the innate immune response to HCV infection and the mechanisms of ISGs to suppress viral survival, as well as the immune evasion strategies for chronic HCV infection.展开更多
The phylogeny and systematics of cordycipitoid fungi have been extensively studied in the last two decades.However,systematic positions of some taxa in the family Cordycipitaceae have not yet been thoroughly resolved....The phylogeny and systematics of cordycipitoid fungi have been extensively studied in the last two decades.However,systematic positions of some taxa in the family Cordycipitaceae have not yet been thoroughly resolved.In this study,a new phylogenetic framework of Cordycipitaceae is reconstructed using multigene(nrSSU,nrLSU,tef-1α,rpb1 and rpb2)sequence data with large-scale taxon sampling.In addition,ITS sequence data of species belonging to the Lecanicillium lineage in the family Cordycipitaceae are used to further determine their phylogenetic placements.Based on molecular phylogenetic data together with morphological evidence,two new genera(Flavocillium and Liangia),16 new species and four new combina-tions are introduced.In the new genus Flavocillium,one new species F.bifurcatum and three new combinations previously described as Lecanicillium,namely F.acerosium,F.primulinium and F.subprimulinium,are proposed.The genus Liangia is built by the new species Lia.sinensis with Lecanicillium-like asexual morph,isolated from an entomopathogenic fungus Beauveria yunnanensis.Due to the absence of Paecilomyces hepiali,an economically and medically significant fungus,in the earlier phylogenetic analyses,its systematic position has been puzzling in both business and academic communities for a long time.Here,P.hepiali is recharacterized using the holotype material along with seven additional samples.It is assigned to the genus Samsoniella(Cordycipitaceae,Hypocreales)possessing Cordyceps-like sexual morph and Isaria-like asexual morph,and thus a new combination,namely S.hepiali is proposed.An additional nine new species in Samsoniella are described:S.alpina,S.antleroides,S.cardinalis,S.cristata,S.lanmaoa,S.kunmingensis,S.ramosa,S.tortricidae and S.yunnanensis.Four new species in Cordyceps are described:C.chaetoclavata,C.cocoonihabita,C.shuifuensis and C.sub-tenuipes.Simplicillium yunnanense,isolated from synnemata of Akanthomyces waltergamsii,is described as a new species.展开更多
Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay be...Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay between climate and land-use change remains poorly understood.Here,we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern China.Specifically,we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate gradients.We found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna ecosystems.These findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic homogenization.The land-use intensity model best explained species richness variation in the tropical rainforest,whereas the climate and land-use intensity interaction model best explained species richness variation in the savanna.These results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna ecosystem.We also found that the response of species composition to climate varied between sites:specifically,species composition was strongly correlated with climatic distance in the tropical rainforest but not in the savanna.Taken together,our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and savanna.These findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change.展开更多
Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in...Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in rare instances host switching can result in Ficus species sharing pollinators.in this study,we examined factors facilitating observed host switching at Xishuangbanna in southwestern(sW)China,where Ficus squamosa is at the northern edge of its range and lacks the fig wasps that pollinate it elsewhere,and its figs are colonized by a Ceratosolen pollinator that routinely breeds in figs of F.heterostyla.Methods We recorded the habitat preferences of F.squamosa and F.heterost-yla at Xishuangbanna,and compared characteristics such as fig size,location and colour at receptive phase.Furthermore,the vegetative and reproductive phenologies in the populations of F.squamosa and F.heterostyla were recorded weekly at Xishuangbanna Tropical botanical garden for 1 year.Important Findings Ficus squamosa is a shrub found near fast-flowing rivers,F.heterostyla is a small tree of disturbed forest edges.although preferring different habitats,they can be found growing close together.both species have figs located at or near ground level,but they differ in size when pollinated.Fig production in F.squamosa was concentrated in the colder months.F.heterostyla produced more figs in summer but had some through-out the year.The absence of its normal pollinators,in combination with similarly located figs and partially complementary fruiting patterns appear to have facilitated colonization of F.squamosa by the routine pollinator of F.heterostyla.The figs probably also share similar attractant volatiles.This host switching suggests one mechanism whereby fig trees can acquire new pollinators and emphasizes the likely significance of edges of ranges in the genesis of novel fig tree-fig wasp relationships.展开更多
One of the most general patterns in ecology is the positive relationship between environmental heterogeneity and local diversity.On the one hand,increased resource heterogeneity provides more resources for diverse con...One of the most general patterns in ecology is the positive relationship between environmental heterogeneity and local diversity.On the one hand,increased resource heterogeneity provides more resources for diverse consumers in the community.On the other hand,increased structural heterogeneity creates variation in the environment’s physical structure,thus allowing the coexistence of diverse species with different environmental requirements.Here,we examined the relative importance of resource and structural heterogeneity in determining the taxonomic,functional,and phylogenetic diversity of nutnesting ants in natural rainforest and rubber plantation.The species richness of nut-nesting ants was 70%higher in rainforest than in rubber plantation.The clustered functional and phylogenetic structure in rubber plantation suggested a strong effect of environmental filtering in shaping ant functional and phylogenetic structure.Nesting heterogeneity(nut diversity)was the major factor explaining variation in taxonomic,functional,and phylogenetic diversity,suggesting that resource heterogeneity plays a major role in shaping the biodiversity patterns of nut-nesting ants.Overall,these results indicate that decreased resource diversity following the conversion of rainforest to rubber plantation can drive biodiversity loss in nut-nesting ants,through its effect on reducing both ant species,functional,and phylogenetic diversity.The decline in species richness and functional and phylogenetic diversity in the local ant community might have major effects on ecosystem functioning.展开更多
Fig trees are important components of tropical forests, because their fruits are eaten by so many vertebrates, but they depend on pollinating fig wasps to produce mature fruits. Disturbance to habitat structure can ha...Fig trees are important components of tropical forests, because their fruits are eaten by so many vertebrates, but they depend on pollinating fig wasps to produce mature fruits. Disturbance to habitat structure can have a major impact on insect diversity and com- position, potentially reducing fruit yields. We investigated the impact of habitat disturbance on the fig wasp community associated with male figs ofFicus tinctoria in Xishuangbanna, China. The community comprised one pollinator species Liporrhopalum gibbosae and six non-pollinating wasp species： Sycoscapter sp. 1, Philotrypesis ravii, Philotrypesis sp. 1, Neosycophila omeomorpha, Sycophila sp.1, and Walkerella sp.1. More disturbed areas were characterized by higher temperatures, less shade, and more vehicle noise. The response of the fig wasp community was complex, with no simple relationship between intensity of disturbance and pollinator abundance. However, the sex ratios （proportion of male progeny） of pollinators increased significantly in more disturbed areas. We conclude that potential changes in fig wasp community composition brought about by disturbance, are unpredictable, with unclear consequences for tropical rainforest biodiversity.展开更多
文摘Hepatitis C virus(HCV) is a major human pathogen of chronic hepatitis and related liver diseases. Innate immunity is the first line of defense against invading foreign pathogens, and its activation is dependent on the recognition of these pathogens by several key sensors. The interferon(IFN) system plays an essential role in the restriction of HCV infection via the induction of hundreds of IFN-stimulated genes(ISGs) that inhibit viral replication and spread. However, numerous factors that trigger immune dysregulation, including viral factors and host genetic factors, can help HCV to escape host immune response, facilitating viral persistence. In this review, we aim to summarize recent advances in understanding the innate immune response to HCV infection and the mechanisms of ISGs to suppress viral survival, as well as the immune evasion strategies for chronic HCV infection.
基金funded by the National Natural Science Foundation of China[31870017,31760011]the Ministry of Science and Technology of the People’s Republic of China[KC1610530]+3 种基金the China Postdoctoral Science Foundation[2017M613017]the Department of Science and Technology of Yunnan Province[2018IA075,2018FY001(-006)]the Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China[2019HJ2096001006]the Biodiversity Investigation,Observation and Assessment Program(2019-2023)of the Ministry of Ecology and Environment of China,and the Yunnan University’s Research Innovation Fund for Graduate Students[YDY17100].
文摘The phylogeny and systematics of cordycipitoid fungi have been extensively studied in the last two decades.However,systematic positions of some taxa in the family Cordycipitaceae have not yet been thoroughly resolved.In this study,a new phylogenetic framework of Cordycipitaceae is reconstructed using multigene(nrSSU,nrLSU,tef-1α,rpb1 and rpb2)sequence data with large-scale taxon sampling.In addition,ITS sequence data of species belonging to the Lecanicillium lineage in the family Cordycipitaceae are used to further determine their phylogenetic placements.Based on molecular phylogenetic data together with morphological evidence,two new genera(Flavocillium and Liangia),16 new species and four new combina-tions are introduced.In the new genus Flavocillium,one new species F.bifurcatum and three new combinations previously described as Lecanicillium,namely F.acerosium,F.primulinium and F.subprimulinium,are proposed.The genus Liangia is built by the new species Lia.sinensis with Lecanicillium-like asexual morph,isolated from an entomopathogenic fungus Beauveria yunnanensis.Due to the absence of Paecilomyces hepiali,an economically and medically significant fungus,in the earlier phylogenetic analyses,its systematic position has been puzzling in both business and academic communities for a long time.Here,P.hepiali is recharacterized using the holotype material along with seven additional samples.It is assigned to the genus Samsoniella(Cordycipitaceae,Hypocreales)possessing Cordyceps-like sexual morph and Isaria-like asexual morph,and thus a new combination,namely S.hepiali is proposed.An additional nine new species in Samsoniella are described:S.alpina,S.antleroides,S.cardinalis,S.cristata,S.lanmaoa,S.kunmingensis,S.ramosa,S.tortricidae and S.yunnanensis.Four new species in Cordyceps are described:C.chaetoclavata,C.cocoonihabita,C.shuifuensis and C.sub-tenuipes.Simplicillium yunnanense,isolated from synnemata of Akanthomyces waltergamsii,is described as a new species.
基金This research was funded by the Biodiversity Conservation Program of the Ministry of Ecology and Environment,China,Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)CAS 135 program(2017XTBG-F01)EPE was supported by subsidy funding to OIST and Japan Society for the Promotion of Science KAKENHI(17K15180).
文摘Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay between climate and land-use change remains poorly understood.Here,we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern China.Specifically,we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate gradients.We found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna ecosystems.These findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic homogenization.The land-use intensity model best explained species richness variation in the tropical rainforest,whereas the climate and land-use intensity interaction model best explained species richness variation in the savanna.These results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna ecosystem.We also found that the response of species composition to climate varied between sites:specifically,species composition was strongly correlated with climatic distance in the tropical rainforest but not in the savanna.Taken together,our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and savanna.These findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change.
基金The Chinese Natural Science Foundation(31372253,31120002)the Young and Middle Aged Academic Leaders of Yunnan Province(2011HB041)the CAS 135 program(XTBG-T01,XTBG-T01,F01).
文摘Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in rare instances host switching can result in Ficus species sharing pollinators.in this study,we examined factors facilitating observed host switching at Xishuangbanna in southwestern(sW)China,where Ficus squamosa is at the northern edge of its range and lacks the fig wasps that pollinate it elsewhere,and its figs are colonized by a Ceratosolen pollinator that routinely breeds in figs of F.heterostyla.Methods We recorded the habitat preferences of F.squamosa and F.heterost-yla at Xishuangbanna,and compared characteristics such as fig size,location and colour at receptive phase.Furthermore,the vegetative and reproductive phenologies in the populations of F.squamosa and F.heterostyla were recorded weekly at Xishuangbanna Tropical botanical garden for 1 year.Important Findings Ficus squamosa is a shrub found near fast-flowing rivers,F.heterostyla is a small tree of disturbed forest edges.although preferring different habitats,they can be found growing close together.both species have figs located at or near ground level,but they differ in size when pollinated.Fig production in F.squamosa was concentrated in the colder months.F.heterostyla produced more figs in summer but had some through-out the year.The absence of its normal pollinators,in combination with similarly located figs and partially complementary fruiting patterns appear to have facilitated colonization of F.squamosa by the routine pollinator of F.heterostyla.The figs probably also share similar attractant volatiles.This host switching suggests one mechanism whereby fig trees can acquire new pollinators and emphasizes the likely significance of edges of ranges in the genesis of novel fig tree-fig wasp relationships.
基金This work was supported by Open Funding from CAS Key Laboratory of Tropical Forest Ecology(No.19CAS-TFE-2)Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)+1 种基金CAS 135 program(2017XTBG-F01)CL was supported by E.O.Wilson Biodiversity Postdoctoral fellowship from the Museum of Comparative Zoology,Harvard University.
文摘One of the most general patterns in ecology is the positive relationship between environmental heterogeneity and local diversity.On the one hand,increased resource heterogeneity provides more resources for diverse consumers in the community.On the other hand,increased structural heterogeneity creates variation in the environment’s physical structure,thus allowing the coexistence of diverse species with different environmental requirements.Here,we examined the relative importance of resource and structural heterogeneity in determining the taxonomic,functional,and phylogenetic diversity of nutnesting ants in natural rainforest and rubber plantation.The species richness of nut-nesting ants was 70%higher in rainforest than in rubber plantation.The clustered functional and phylogenetic structure in rubber plantation suggested a strong effect of environmental filtering in shaping ant functional and phylogenetic structure.Nesting heterogeneity(nut diversity)was the major factor explaining variation in taxonomic,functional,and phylogenetic diversity,suggesting that resource heterogeneity plays a major role in shaping the biodiversity patterns of nut-nesting ants.Overall,these results indicate that decreased resource diversity following the conversion of rainforest to rubber plantation can drive biodiversity loss in nut-nesting ants,through its effect on reducing both ant species,functional,and phylogenetic diversity.The decline in species richness and functional and phylogenetic diversity in the local ant community might have major effects on ecosystem functioning.
基金Acknowledgments The authors would like to thank Professor Jean-Yves Rusplus for identifying the fig wasps of Ficus tinctoria. We wish to thank Stephen Compton for providing help with statistical methods and revising the manuscript. We also thank Iain Taylor, Paolo Pelosi, Roy Turkington, Loren Bell and Kari Malen and anonymous referees for good suggestions and reviewing the manuscript. The authors also thank Zhen-Ji Wang, Jun-Ming Guan, Pei Yang and Yi Zhao for their help with the fieldwork. The study was funded by the Chinese Natural Science Foundation （30571507, 30670358）.
文摘Fig trees are important components of tropical forests, because their fruits are eaten by so many vertebrates, but they depend on pollinating fig wasps to produce mature fruits. Disturbance to habitat structure can have a major impact on insect diversity and com- position, potentially reducing fruit yields. We investigated the impact of habitat disturbance on the fig wasp community associated with male figs ofFicus tinctoria in Xishuangbanna, China. The community comprised one pollinator species Liporrhopalum gibbosae and six non-pollinating wasp species： Sycoscapter sp. 1, Philotrypesis ravii, Philotrypesis sp. 1, Neosycophila omeomorpha, Sycophila sp.1, and Walkerella sp.1. More disturbed areas were characterized by higher temperatures, less shade, and more vehicle noise. The response of the fig wasp community was complex, with no simple relationship between intensity of disturbance and pollinator abundance. However, the sex ratios （proportion of male progeny） of pollinators increased significantly in more disturbed areas. We conclude that potential changes in fig wasp community composition brought about by disturbance, are unpredictable, with unclear consequences for tropical rainforest biodiversity.
