Mitochondrial gene fragments of 16S rRNA gene of four species （Rhacophorus rhodopus, R. reinwardtii, Philautus albopunctatus and P. rhododiscus ） from 11 populations were sequenced in this study. Homologous sequence...Mitochondrial gene fragments of 16S rRNA gene of four species （Rhacophorus rhodopus, R. reinwardtii, Philautus albopunctatus and P. rhododiscus ） from 11 populations were sequenced in this study. Homologous sequences of R. bipunctatus, Theloderma asperum, T. corticale and Buergeria japonica were obtained by screening the GenBank database. After excluding all gaps and ambiguous positions, aligned sequences were 500 bp in length with 115 variable sites and 92 parsimony-informative sites. Using B .japonica as an outgroup, phylogenetic relationships were analyzed using Bayesian inference, maximum parsimony and maximum likelihood methods. Our results indicated that neither of R. rhodopus and P. albopunctatus were monophyletic at the species level. The population of R. rhodopus from Hainan Island was more close to R. bipunctatus than to populations of R. rhodopus from Yunnan Province. Furthermore, the populations of R. rhodopus from Yunnan Province can be divided into two main lineages. Theloderma corticale and P.rhododiscus were clustered together and T. asperum was nested in P.albopunctatus. We considered that P. albopunctatus Liu and Hu, 1962, was the synonymy of T. asperum Boulenger, 1886, and suggested removing P. rhododiscus from Philautus into the genus Theloderma.展开更多
We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the...We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the staging of development was based on morphological and physiological characteristics. Two major periods of development were designated： i） early embryonic period, from fertilization to operculum completion stage, lasted for 324 h at water temperature （WT） 18 ？23℃; ii） larval period, from operculum completion stage to tail absorbed stage, took 1207 h at WT 20 ？ 24℃. Tadpoles of the concave-eared torrent frogs showed no evidence of abdominal sucker. Absence of this key characteristic supports the view from molecular systematics that concave-eared torrent frog does not belong to the genus Amolops. Two cleavage patterns were observed in embryos at 8-cell and 16-cell stages, with Pattern I2 （latitudinal cleavage at the 8-cell stage, and meridional cleavage at the 16-cell stage with two perpendicular meridional furrows） being the predominant pattern and only 1.5% belonging to Pattern II （meridional cleavage at the 8-cell stage and latitudinal cleavage at the 16-cell stage）. The factors affecting cleavage and hatching ratios, developmental speed, and ecological adaptation were discussed.展开更多
Accumulated evidence indicates that the activating transcription factor 4（atf4） is a developmentally relevant gene.Here,we report on the characterization of atf4 in Xenopus embryos,which is differentially expressed ...Accumulated evidence indicates that the activating transcription factor 4（atf4） is a developmentally relevant gene.Here,we report on the characterization of atf4 in Xenopus embryos,which is differentially expressed in the central nervous system,eyes,blood,and the pronephros,as well as in developing endodermal organs such as the stomach,duodenum,liver,and pancreas.Ectopic expression of atf4 in the animal hemisphere of Xenopus embryos had no obvious effects on the induction of neural progenitors,but suppressed neurogenesis and eye formation without promoting apoptosis.Our data suggest that tightly controlled atf4 activities may be crucial for normal neurogenesis and early eye patterning.展开更多
基金Supported by the National Natural Science Foundation of China (30670243)
文摘Mitochondrial gene fragments of 16S rRNA gene of four species （Rhacophorus rhodopus, R. reinwardtii, Philautus albopunctatus and P. rhododiscus ） from 11 populations were sequenced in this study. Homologous sequences of R. bipunctatus, Theloderma asperum, T. corticale and Buergeria japonica were obtained by screening the GenBank database. After excluding all gaps and ambiguous positions, aligned sequences were 500 bp in length with 115 variable sites and 92 parsimony-informative sites. Using B .japonica as an outgroup, phylogenetic relationships were analyzed using Bayesian inference, maximum parsimony and maximum likelihood methods. Our results indicated that neither of R. rhodopus and P. albopunctatus were monophyletic at the species level. The population of R. rhodopus from Hainan Island was more close to R. bipunctatus than to populations of R. rhodopus from Yunnan Province. Furthermore, the populations of R. rhodopus from Yunnan Province can be divided into two main lineages. Theloderma corticale and P.rhododiscus were clustered together and T. asperum was nested in P.albopunctatus. We considered that P. albopunctatus Liu and Hu, 1962, was the synonymy of T. asperum Boulenger, 1886, and suggested removing P. rhododiscus from Philautus into the genus Theloderma.
基金supported by the National Natural Science Fundation of China(30730029)
文摘We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the staging of development was based on morphological and physiological characteristics. Two major periods of development were designated： i） early embryonic period, from fertilization to operculum completion stage, lasted for 324 h at water temperature （WT） 18 ？23℃; ii） larval period, from operculum completion stage to tail absorbed stage, took 1207 h at WT 20 ？ 24℃. Tadpoles of the concave-eared torrent frogs showed no evidence of abdominal sucker. Absence of this key characteristic supports the view from molecular systematics that concave-eared torrent frog does not belong to the genus Amolops. Two cleavage patterns were observed in embryos at 8-cell and 16-cell stages, with Pattern I2 （latitudinal cleavage at the 8-cell stage, and meridional cleavage at the 16-cell stage with two perpendicular meridional furrows） being the predominant pattern and only 1.5% belonging to Pattern II （meridional cleavage at the 8-cell stage and latitudinal cleavage at the 16-cell stage）. The factors affecting cleavage and hatching ratios, developmental speed, and ecological adaptation were discussed.
基金supported in part by funds from the Key Project of Knowledge Innovation Program of the Chinese Academy of Sciences(KSCX2-YW-R-083)the National Basic Research Program of China(2009CB941202)
文摘Accumulated evidence indicates that the activating transcription factor 4（atf4） is a developmentally relevant gene.Here,we report on the characterization of atf4 in Xenopus embryos,which is differentially expressed in the central nervous system,eyes,blood,and the pronephros,as well as in developing endodermal organs such as the stomach,duodenum,liver,and pancreas.Ectopic expression of atf4 in the animal hemisphere of Xenopus embryos had no obvious effects on the induction of neural progenitors,but suppressed neurogenesis and eye formation without promoting apoptosis.Our data suggest that tightly controlled atf4 activities may be crucial for normal neurogenesis and early eye patterning.
