Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase...Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase in relevant phylogenetic studies,our understanding of between species relatedness in Caenogastropoda has improved.However,the biodiversity,taxonomic status,and phylogenetic relationships of this group remain unclear.In the present study,we performed next-generation sequencing of four complete mitochondrial genomes from three families(Buccinidae,Columbellidae,and Cypraeidae)and the four mitogenomes were classical circular structures,with a length of 16177 bp in Volutharpa ampullacea,16244 bp in Mitrella albuginosa,16926bp in Mauritia arabica asiatica and 15422 bp in Erronea errones.Base composition analysis indicated that whole sequences were biased toward A and T.Then compared them with 171 complete mitochondrial genomes of Caenogastropoda.The phylogenetic relationship of Caenogastropoda derived from Maximum Likelihood(ML)and Bayesian Inference(BI)trees constructed based on CDS sequences was consistent with the results of traditional morphological analysis,with all three families showing close relationships.This study supported Caenogastropoda at the molecular level as a separate clade of Mollusca.According to our divergence time estimations,Caenogastropoda was formed during the middle Triassic period(~247.2–237 Ma).Our novel mitochondrial genomes provide evidence for the speciation of Caenogastropoda in addition to elucidating the mitochondrial genomic evolution of this subclass.展开更多
The polymerase chain reaction combined with direct sequencing was employed to deduce the variety of the grey-rumped pheasant populations in China.Totally 1079 basepair sequences of mitochondrial DNA (mtDNA) control-re...The polymerase chain reaction combined with direct sequencing was employed to deduce the variety of the grey-rumped pheasant populations in China.Totally 1079 basepair sequences of mitochondrial DNA (mtDNA) control-region gene were analyzed from 121 grey-rumped pheasants obtained from 13 Chinese localities, 76 variable sites resulted in 91 haplotypes.These populations possessed a high level of genetic diversity, indicating that during their evolution effective population size and polymorphism were not reduced by climatic fluctuations in the Pleistocene ice ages.Phylogenetic analysis indicates that all populations were clustered into two groups, western and eastern.The degree of population differentiation presumably results from a low gene flow (Nm=0.33, Fst=0.60, P<0.001) between the two groups, and the divergence occurred in the years (2.1×105 -2.2×105).The genetic structure of grey-rumped pheasants in China appears to be the result of the uplift of Qinghai-Tibet Plateau, the existence of Qinling Mountains and Liupan Mountains and cyclical climatic oscillations during the late Pleistocene.展开更多
Heteroconchia,a widespread and abundant aquatic invertebrate,is an important clade of bivalve mollusks.The relationship between the three branches of Heteroconchia,Palaeoheterodonta,Archiheterodonta,and Euheterodonta ...Heteroconchia,a widespread and abundant aquatic invertebrate,is an important clade of bivalve mollusks.The relationship between the three branches of Heteroconchia,Palaeoheterodonta,Archiheterodonta,and Euheterodonta has become a main controversy in molecular studies of the relationships between bivalves.In the present study,we assembled the complete mitochondrial genomes of Tapes dorsatus(Veneridae)and Cardita variegata(Carditidae)using high-throughput sequencing.C.variegata is the first mitochondrial genome belonging to the family Carditidae to be reported.We used 12 protein coding genes(excluding atp8)from the complete mitochondrial genomes of 146 species to recover the internal relationships of Heteroconchia.Our results support the traditional view of early branching of Palaeoheterodonta and the recovery of the monophyly of Palaeoheterodonta,Anomalodesmata,Imparidentia.Rearrangement analysis show that gene arrangement within Venerida was highly variable.Time-calibrated phylogenetic studies based on a relaxed molecular clock model suggested that Veneridae originated approximately 337.62 million years ago(Ma)and split into two major clades,whereas Carditidae originated approximately 510.09 Ma.Our results provide evidence of the internal relationships of Heteroconchia.展开更多
基金Research and Development Program of Shandong Province,China(Major Science and Technology Innovation Project)under contract No.2021CXGC011306MNR Key Laboratory of Eco-Environmental Science and Technology,China under contract No.MEEST-2021-05+2 种基金Natural Science Foundation of Shandong Province under contract No.ZR2020MD002Doctoral Science Research Foundation of Yantai University under contract Nos SM15B01,SM19B70 and SM19B28Double-Hundred Action of Yantai City under contract No.2320004-SM20RC02。
文摘Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase in relevant phylogenetic studies,our understanding of between species relatedness in Caenogastropoda has improved.However,the biodiversity,taxonomic status,and phylogenetic relationships of this group remain unclear.In the present study,we performed next-generation sequencing of four complete mitochondrial genomes from three families(Buccinidae,Columbellidae,and Cypraeidae)and the four mitogenomes were classical circular structures,with a length of 16177 bp in Volutharpa ampullacea,16244 bp in Mitrella albuginosa,16926bp in Mauritia arabica asiatica and 15422 bp in Erronea errones.Base composition analysis indicated that whole sequences were biased toward A and T.Then compared them with 171 complete mitochondrial genomes of Caenogastropoda.The phylogenetic relationship of Caenogastropoda derived from Maximum Likelihood(ML)and Bayesian Inference(BI)trees constructed based on CDS sequences was consistent with the results of traditional morphological analysis,with all three families showing close relationships.This study supported Caenogastropoda at the molecular level as a separate clade of Mollusca.According to our divergence time estimations,Caenogastropoda was formed during the middle Triassic period(~247.2–237 Ma).Our novel mitochondrial genomes provide evidence for the speciation of Caenogastropoda in addition to elucidating the mitochondrial genomic evolution of this subclass.
基金Supported by Natural Science Foundation of Hainan Province(NO:311055)Doctoral Start-up Research Fund of Qiongzhou University(No:QYXB201009)+1 种基金Co-operation Fund between University and Locality of Sanya City(No:2010YD22)Fund for Zoology Major Course of Hainan Province
文摘The polymerase chain reaction combined with direct sequencing was employed to deduce the variety of the grey-rumped pheasant populations in China.Totally 1079 basepair sequences of mitochondrial DNA (mtDNA) control-region gene were analyzed from 121 grey-rumped pheasants obtained from 13 Chinese localities, 76 variable sites resulted in 91 haplotypes.These populations possessed a high level of genetic diversity, indicating that during their evolution effective population size and polymorphism were not reduced by climatic fluctuations in the Pleistocene ice ages.Phylogenetic analysis indicates that all populations were clustered into two groups, western and eastern.The degree of population differentiation presumably results from a low gene flow (Nm=0.33, Fst=0.60, P<0.001) between the two groups, and the divergence occurred in the years (2.1×105 -2.2×105).The genetic structure of grey-rumped pheasants in China appears to be the result of the uplift of Qinghai-Tibet Plateau, the existence of Qinling Mountains and Liupan Mountains and cyclical climatic oscillations during the late Pleistocene.
基金Acknowledgments Financial support was provided by the National Natural Science Foundation of China (No. 30530130), Dr Start-up Fund Research of Qiongzhou Univer- sity (No. QYXB201009) and the Co-operation Fund Between University and Locality, Sanya (No. 2010YD22) for funding this research.
基金Supported by the Research and Development Program of Shandong Province,China(Major Science and Technology Innovation Project)(No.2021CXGC011306)the MNR Key Laboratory of Eco-Environmental Science and Technology,China(No.MEEST-2021-05)+2 种基金the Natural Science Foundation of Shandong Province(No.ZR2020MD002)the Doctoral Science Research Foundation of Yantai University(Nos.SM15B01,SM19B70,SM19B28)the“Double-Hundred Action”of Yantai City(No.2320004-SM20RC02)。
文摘Heteroconchia,a widespread and abundant aquatic invertebrate,is an important clade of bivalve mollusks.The relationship between the three branches of Heteroconchia,Palaeoheterodonta,Archiheterodonta,and Euheterodonta has become a main controversy in molecular studies of the relationships between bivalves.In the present study,we assembled the complete mitochondrial genomes of Tapes dorsatus(Veneridae)and Cardita variegata(Carditidae)using high-throughput sequencing.C.variegata is the first mitochondrial genome belonging to the family Carditidae to be reported.We used 12 protein coding genes(excluding atp8)from the complete mitochondrial genomes of 146 species to recover the internal relationships of Heteroconchia.Our results support the traditional view of early branching of Palaeoheterodonta and the recovery of the monophyly of Palaeoheterodonta,Anomalodesmata,Imparidentia.Rearrangement analysis show that gene arrangement within Venerida was highly variable.Time-calibrated phylogenetic studies based on a relaxed molecular clock model suggested that Veneridae originated approximately 337.62 million years ago(Ma)and split into two major clades,whereas Carditidae originated approximately 510.09 Ma.Our results provide evidence of the internal relationships of Heteroconchia.