Blarinellini is a tribe of soricine shrews comprised of nine fossil genera and one extant genus. Blarinelline shrews were once widely distributed throughout Eurasia and North America, though only members of the Asiati...Blarinellini is a tribe of soricine shrews comprised of nine fossil genera and one extant genus. Blarinelline shrews were once widely distributed throughout Eurasia and North America, though only members of the Asiatic short-tailed shrew genus Blarinella currently persist （mostly in southwestern China and adjacent areas）. Only three forms of Blarinella have been recognized as either species or subspecies However, recent molecular studies indicated a strikingly deep divergence within the genus, implying the existence of a distinct genus-level lineage. We sequenced the complete mitochondrial genomes and one nuclear gene of three Asiatic short-tailed and two North American shrews and analyzed them morphometrically and morphologically. Our molecular analyses revealed that specimens ascribed to B. griselda formed two deeply diverged lineages, one a close relative to B. quadraticauda, whereas the other--comprised of topotype specimens from southern Gansu-iverged from other Blarinella in the middle Miocene （ca. 18.2 million years ago （Ma）, 95% confidence interval=13.4-23.6 Ma）. Although the skulls were similarly shaped in both lineages, we observed several diagnostic characteristics, including the shape of the upper p4. In consideration of the molecular and morphological evidence, we recognize B. griselda as the sole species of a new genus, namely, Pantherina gen. nov. Interestingly, some characteristics of Pantherina griselda are more similar to fossil genera, suggesting it represents an evolutionarily more primitive form than Blarinella.Recognition of this new genus sheds light on the systematics and evolutionary history of the tribe Blarinellini throughout Eurasia and North America.展开更多
The characterization of the human T-cell receptor （TCR） repertoire has made remarkable progress, with most of the work focusing on the TCRβ chains. Here, we ana- lyzed the diversity and complexity of both the TCRa ...The characterization of the human T-cell receptor （TCR） repertoire has made remarkable progress, with most of the work focusing on the TCRβ chains. Here, we ana- lyzed the diversity and complexity of both the TCRa and TCRβ repertoires of three healthy donors. We found that the diversity of the TCRα repertoire is higher than that of the TCRβ repertoire, whereas the usages of the V and J genes tended to be preferential with similar TRAV and TRAJ patterns in all three donors. The V-J pairings, like the V and J gene usages, were slightly preferential. We also found that the TRDV1 gene rearranges with the majority of TRAJ genes, suggesting that TRDV1 is a shared TRAV/DV gene （TRAV42/DV1）. Moreover, we uncovered the presence of tandem TRBD （TRB D gene） usage in -2% of the productive human TCRβ CDR3 sequences.展开更多
基金supported by a Natural Sciences and Engineering Research Council(NSERC)of Canada Discovery Grant(RGPIN/238838-2011)NSERC Discovery Accelerator Supplement(RGPAS/412336-2011)+2 种基金University of Manitoba Research Grants Program Award(#41342)to K.L.C.K.H. was supported by the Youth Innovation Promotion AssociationChinese Academy of Sciencesa JSPS Postdoctoral Fellowship for Overseas Researchers(P16092)
文摘Blarinellini is a tribe of soricine shrews comprised of nine fossil genera and one extant genus. Blarinelline shrews were once widely distributed throughout Eurasia and North America, though only members of the Asiatic short-tailed shrew genus Blarinella currently persist （mostly in southwestern China and adjacent areas）. Only three forms of Blarinella have been recognized as either species or subspecies However, recent molecular studies indicated a strikingly deep divergence within the genus, implying the existence of a distinct genus-level lineage. We sequenced the complete mitochondrial genomes and one nuclear gene of three Asiatic short-tailed and two North American shrews and analyzed them morphometrically and morphologically. Our molecular analyses revealed that specimens ascribed to B. griselda formed two deeply diverged lineages, one a close relative to B. quadraticauda, whereas the other--comprised of topotype specimens from southern Gansu-iverged from other Blarinella in the middle Miocene （ca. 18.2 million years ago （Ma）, 95% confidence interval=13.4-23.6 Ma）. Although the skulls were similarly shaped in both lineages, we observed several diagnostic characteristics, including the shape of the upper p4. In consideration of the molecular and morphological evidence, we recognize B. griselda as the sole species of a new genus, namely, Pantherina gen. nov. Interestingly, some characteristics of Pantherina griselda are more similar to fossil genera, suggesting it represents an evolutionarily more primitive form than Blarinella.Recognition of this new genus sheds light on the systematics and evolutionary history of the tribe Blarinellini throughout Eurasia and North America.
基金We thank Dr. Christopher J. Vavrickafor and Boris Tefsen for their critical reading and revision of the manuscript and Dr. Miles P. Dav- enport for his inspiring discussions. This work is supported by the National Natural Science Foundation of China （NSFC, Grant No. 31030030）, the National Basic Research Program （973 Program） （No. 2013CB531500） and the National Natural Science Foundation of China （Grant No. 81373141 ）. G.F.G. is a leading principal investigator of the NSFC Innovative Research Group （Grant No. 81321063）.
文摘The characterization of the human T-cell receptor （TCR） repertoire has made remarkable progress, with most of the work focusing on the TCRβ chains. Here, we ana- lyzed the diversity and complexity of both the TCRa and TCRβ repertoires of three healthy donors. We found that the diversity of the TCRα repertoire is higher than that of the TCRβ repertoire, whereas the usages of the V and J genes tended to be preferential with similar TRAV and TRAJ patterns in all three donors. The V-J pairings, like the V and J gene usages, were slightly preferential. We also found that the TRDV1 gene rearranges with the majority of TRAJ genes, suggesting that TRDV1 is a shared TRAV/DV gene （TRAV42/DV1）. Moreover, we uncovered the presence of tandem TRBD （TRB D gene） usage in -2% of the productive human TCRβ CDR3 sequences.
