Pancreatic ribonuclease,which is encoded by RNase1,is a digestive enzyme secreted by the pancreas of vertebrates,and has been recognized to be a classic example for molecular evolutionary studies due to the frequent o...Pancreatic ribonuclease,which is encoded by RNase1,is a digestive enzyme secreted by the pancreas of vertebrates,and has been recognized to be a classic example for molecular evolutionary studies due to the frequent occurrence of gene duplication and functional divergence in organisms（Zhang et al.,2002,2006;Yu and Zhang,2006;Yu et al.,2010;Xu et al.,2013;Liu et al.,2014）.RNase1 has been extensively studied in many mammals,展开更多
Ribonuclease 6(RNase6 or RNase K6)is a protein that belongs to a superfamily thought to be the sole vertebrate-specific enzyme known for a wide range of physiological functions,including digestion,cytotoxicity,a...Ribonuclease 6(RNase6 or RNase K6)is a protein that belongs to a superfamily thought to be the sole vertebrate-specific enzyme known for a wide range of physiological functions,including digestion,cytotoxicity,angiogenesis,male reproduction and host defense.In our study,51 functional genes and 11 pseudogenes were identified from 27 Rodentia species.Intriguingly,in the 3 main lineages of rodents there were multiple RNase6s identified in all species of Ctenohystrica,whereas only a single RNase6 was observed in other Rodentia species examined except for 2 species in the mouse-related clade.The evolutionary scenario of“birth(gene duplication)and death(gene deactivation)”and gene sorting have been demonstrated in Ctenohystrica.In addition,bursts of positive selection,diversification of isoelectric point and positive net charge have been identified in Ctenohystrica,especially at two key sites that are involved in antimicrobial function.Site Trp30 has undergone positive selection and Ile45 has changed into other residues in Group B and Group C of the Ctenohystrica.Our results demonstrated a complex and intriguing evolutionary pattern of rodent RNase6,and indicated that functional modification may have occurred,which establishes an important theoretical foundation for future functional assays in rodent RNase6.展开更多
Monospecific and bispecific genera are of special concern as they represent unique phylogenetic/evolutionary trajectories within larger clades.In addition,as phylogenetically older taxa are supposed to be exposed to h...Monospecific and bispecific genera are of special concern as they represent unique phylogenetic/evolutionary trajectories within larger clades.In addition,as phylogenetically older taxa are supposed to be exposed to higher rarity and extinction risk,monospecific and bispecific genera may be intrinsically more prone to extinction risks than multispecies genera,although extinction risks also depend on the ecological and biological strategy of the species.Here,the distribution across biogeographical zones and the levels of threat to 2 speciose orders of mammals(monospecific and bispecific genera of Rodentia and Soricomorpha)are investigated in order to highlight major patterns at the worldwide scale.In Rodentia,39.7%of the genera(n=490)were monospecific and 17.9%were bispecific.In Soricomorpha,44.4%of the total genera(n=45)were monospecific and 15%were bispecific.There was a positive correlation between the number of monospecific genera and the total number of genera per family.Peaks of monospecific and bispecific genera richness were observed in Neotropical,Oriental and Afrotropical regions in rodents and in the Palearctic region in soricomorphs.Range size was significantly uneven across biogeographic region in rodents(with larger ranges in Nearctic and Oriental regions and smaller ranges in the Australian region),but there was no difference across biogeographic regions in terms of range size in soricomorphs.Most of the monospecific and bispecific genera occurred in forest habitat in both taxa.The frequency distribution of the monospecific and bispecific genera across IUCN categories did not differ significantly from the expected pattern using the total rodent genera and the multispecies genera.展开更多
基金supported by grants from the Yunnan Provincial Education Fund project in Scientific Research to X.P.W.(No.2015Y003)the Yunnan Applied Basic Research Project to D.T.Lthe National Youth Talent Support Program to L.Y
文摘Pancreatic ribonuclease,which is encoded by RNase1,is a digestive enzyme secreted by the pancreas of vertebrates,and has been recognized to be a classic example for molecular evolutionary studies due to the frequent occurrence of gene duplication and functional divergence in organisms（Zhang et al.,2002,2006;Yu and Zhang,2006;Yu et al.,2010;Xu et al.,2013;Liu et al.,2014）.RNase1 has been extensively studied in many mammals,
基金the Yunnan Applied Basic Research Project(2017FD148)the State Key Basic Research and Development Plan in Kunming Institute of Zoology(GREKF17-02,to DTL)the National Natural Science Foundation of China(31760619,to XPW).
文摘Ribonuclease 6(RNase6 or RNase K6)is a protein that belongs to a superfamily thought to be the sole vertebrate-specific enzyme known for a wide range of physiological functions,including digestion,cytotoxicity,angiogenesis,male reproduction and host defense.In our study,51 functional genes and 11 pseudogenes were identified from 27 Rodentia species.Intriguingly,in the 3 main lineages of rodents there were multiple RNase6s identified in all species of Ctenohystrica,whereas only a single RNase6 was observed in other Rodentia species examined except for 2 species in the mouse-related clade.The evolutionary scenario of“birth(gene duplication)and death(gene deactivation)”and gene sorting have been demonstrated in Ctenohystrica.In addition,bursts of positive selection,diversification of isoelectric point and positive net charge have been identified in Ctenohystrica,especially at two key sites that are involved in antimicrobial function.Site Trp30 has undergone positive selection and Ile45 has changed into other residues in Group B and Group C of the Ctenohystrica.Our results demonstrated a complex and intriguing evolutionary pattern of rodent RNase6,and indicated that functional modification may have occurred,which establishes an important theoretical foundation for future functional assays in rodent RNase6.
文摘Monospecific and bispecific genera are of special concern as they represent unique phylogenetic/evolutionary trajectories within larger clades.In addition,as phylogenetically older taxa are supposed to be exposed to higher rarity and extinction risk,monospecific and bispecific genera may be intrinsically more prone to extinction risks than multispecies genera,although extinction risks also depend on the ecological and biological strategy of the species.Here,the distribution across biogeographical zones and the levels of threat to 2 speciose orders of mammals(monospecific and bispecific genera of Rodentia and Soricomorpha)are investigated in order to highlight major patterns at the worldwide scale.In Rodentia,39.7%of the genera(n=490)were monospecific and 17.9%were bispecific.In Soricomorpha,44.4%of the total genera(n=45)were monospecific and 15%were bispecific.There was a positive correlation between the number of monospecific genera and the total number of genera per family.Peaks of monospecific and bispecific genera richness were observed in Neotropical,Oriental and Afrotropical regions in rodents and in the Palearctic region in soricomorphs.Range size was significantly uneven across biogeographic region in rodents(with larger ranges in Nearctic and Oriental regions and smaller ranges in the Australian region),but there was no difference across biogeographic regions in terms of range size in soricomorphs.Most of the monospecific and bispecific genera occurred in forest habitat in both taxa.The frequency distribution of the monospecific and bispecific genera across IUCN categories did not differ significantly from the expected pattern using the total rodent genera and the multispecies genera.
