Sequence variation of partial cytochrome b genes between two Coilia species, C. ectenes and C. mystus, was in- vestigated. Of the 402 nucleotides, twenty-seven (6.72%) are polymorphic and all are synonymous substituti...Sequence variation of partial cytochrome b genes between two Coilia species, C. ectenes and C. mystus, was in- vestigated. Of the 402 nucleotides, twenty-seven (6.72%) are polymorphic and all are synonymous substitutions. At the third positions of genetic condon of cytochrome b gene, the two species show an extreme anti-G bias (<4%) and a pronounced bias towards A and C (>68%). There is no amino acid sequence divergence between the partial cytochrome b genes of the two species, indicating a close genetic relationship between them. The k-2p genetic distance of partial cytochrome b segment of the two species is 0.072, suggesting that the species were separated 3.6 Ma ago, in the middle Pliocene. Our result reveals that the cytochrome b gene is an appropriate marker for studies of population genetic structures and phylogeographic pat- terns of the two species.展开更多
With the rapid development of social economy and the progress of science and technology, Chinas industrial production has developed rapidly, and the demand for industrial factories has gradually increased. Industrial ...With the rapid development of social economy and the progress of science and technology, Chinas industrial production has developed rapidly, and the demand for industrial factories has gradually increased. Industrial steel structure is widely used in various industries because of its advantages of fast construction speed, high bearing capacity, high earthquake resistance, energy saving and environmental protection. When applying steel structure workshop, it is necessary to select environmentally-friendly and durable steel structure materials according to the different environments, uses and demands of industrial workshop, and design reasonably according to the production process requirements and the actual situation of the site, so as to meet the requirements of advanced technology, economy, rationality, safety and applicability. Based on this, this paper analyzes the application of steel structure design in industrial workshop structure design, hoping to provide reference for relevant practitioners.展开更多
Both the rhino mouse and hairless mouse resulted from hairless gene mutation, but they show different phenotypes of skin physiology. The rhino mouse has more similar histological characters to human papular alopecia.T...Both the rhino mouse and hairless mouse resulted from hairless gene mutation, but they show different phenotypes of skin physiology. The rhino mouse has more similar histological characters to human papular alopecia.Therefore rhino mouse is a good experimental animal model for human papular alopecia. This study reports a hairless mouse named rhino KIZ, arose from KM colony in Kunming Institue of Zoology, by systematic studies on morphology,skin histopathology, gene sequence, pedigree and protein domain analysis. The results demonstrate that a C-to-T transition in exon 11 of hr gene (The mutant gene has been applied for a Chinese patent (patent No. 03135280)) results in the rhino KIZ. The rhino KIZ with clear genetic mechanism will be a useful animal model.展开更多
Pituitary growth hormone (GH) evolves very slowly in most of mammals, but the evolutionary rates ap- pear to have increased markedly on two occasions during the evolution of primates and ruminants. To investigate the ...Pituitary growth hormone (GH) evolves very slowly in most of mammals, but the evolutionary rates ap- pear to have increased markedly on two occasions during the evolution of primates and ruminants. To investigate the evo- lutionary pattern of growth hormone receptor (GHR), we sequenced the extracellular domain of GHR genes from four primate species. Our results suggested that GHR in mammal also shows an episodic evolutionary pattern, which is consis- tent with that observed in pituitary growth hormone. Fur- ther analysis suggested that this pattern of rapid evolution observed in primates and ruminants is likely the result of coevolution between pituitary growth hormone and its re- ceptor.展开更多
Due to its specific characteristics, such as ma-ternal inheritance and absence of recombination, each mtDNA belongs to certain monophyletic clade in the rooted mtDNA tree (haplogroup) according to the mutations it har...Due to its specific characteristics, such as ma-ternal inheritance and absence of recombination, each mtDNA belongs to certain monophyletic clade in the rooted mtDNA tree (haplogroup) according to the mutations it harbors. Rare mutation (excluding parallel mutation) occur-ring at multiple times in different haplogroups could thus be a potential reading error according to the mtDNA phylogeny. This experience has been widely used in double-checking the credibility of the rare mutations in human mtDNA sequences. However, no test has been performed so far for the feasibility of applying this strategy to the rare insertion/deletion (indel) events in mtDNA sequences. In this study, we attempted to relate the rare indels in mtDNAs to their haplogroup status in a total of 2352 individuals from 50 populations in China. Our results show that the insertion of A at position 16259 is restricted to a subclade of haplogroup C and can be verified. The other indel polymorphisms, which occur in the repeat of the deleted or inserted nucleotide(s), may not be distin-guished from phantom mutations from a phylogenetic point of view. Independently and multiply sequencing the frag-ment with the indel is the best and the most reliable way for confirmation.展开更多
In the present study, we obtained exon 2―5 of prolactin (PRL) gene from four primate species by PCR and sequencing. Adding other genes available in GenBank, we calculate amino acid substitution rates for prolactin ge...In the present study, we obtained exon 2―5 of prolactin (PRL) gene from four primate species by PCR and sequencing. Adding other genes available in GenBank, we calculate amino acid substitution rates for prolactin gene in primate. Comparison of nonsynonymous substitution rate to synonymous substitution rate ratios shows no evidence of positive selection for any lineage of primate prolactin gene. According to this and the facts that (i) no sites under positive selection are inferred by using maximum-likelihood method; (ii) among 32 amino acid replacement that occurred along the rapid evolutionary phase, only two are included in the 40 functionally important residues, indicating that amino acid replacement tends to occur in those functionally unimportant residues; (iii) partial of prolactin function is replaced by pla-cental lactogen in primate at the rapid evolutionary phase of prolactin gene, we thus deem that it is relaxation of purifying selection to some extent rather than positive selection that enforces the rapid evolution of primate prolactin gene.展开更多
基金the Major State Basic Research Development Program(G19990437).
文摘Sequence variation of partial cytochrome b genes between two Coilia species, C. ectenes and C. mystus, was in- vestigated. Of the 402 nucleotides, twenty-seven (6.72%) are polymorphic and all are synonymous substitutions. At the third positions of genetic condon of cytochrome b gene, the two species show an extreme anti-G bias (<4%) and a pronounced bias towards A and C (>68%). There is no amino acid sequence divergence between the partial cytochrome b genes of the two species, indicating a close genetic relationship between them. The k-2p genetic distance of partial cytochrome b segment of the two species is 0.072, suggesting that the species were separated 3.6 Ma ago, in the middle Pliocene. Our result reveals that the cytochrome b gene is an appropriate marker for studies of population genetic structures and phylogeographic pat- terns of the two species.
文摘With the rapid development of social economy and the progress of science and technology, Chinas industrial production has developed rapidly, and the demand for industrial factories has gradually increased. Industrial steel structure is widely used in various industries because of its advantages of fast construction speed, high bearing capacity, high earthquake resistance, energy saving and environmental protection. When applying steel structure workshop, it is necessary to select environmentally-friendly and durable steel structure materials according to the different environments, uses and demands of industrial workshop, and design reasonably according to the production process requirements and the actual situation of the site, so as to meet the requirements of advanced technology, economy, rationality, safety and applicability. Based on this, this paper analyzes the application of steel structure design in industrial workshop structure design, hoping to provide reference for relevant practitioners.
文摘Both the rhino mouse and hairless mouse resulted from hairless gene mutation, but they show different phenotypes of skin physiology. The rhino mouse has more similar histological characters to human papular alopecia.Therefore rhino mouse is a good experimental animal model for human papular alopecia. This study reports a hairless mouse named rhino KIZ, arose from KM colony in Kunming Institue of Zoology, by systematic studies on morphology,skin histopathology, gene sequence, pedigree and protein domain analysis. The results demonstrate that a C-to-T transition in exon 11 of hr gene (The mutant gene has been applied for a Chinese patent (patent No. 03135280)) results in the rhino KIZ. The rhino KIZ with clear genetic mechanism will be a useful animal model.
基金This work was supported by Yunnan Science and Technology Commitee,and the National Natural Science Foundation of China(Grant Nos.30021004&3043010).
文摘Pituitary growth hormone (GH) evolves very slowly in most of mammals, but the evolutionary rates ap- pear to have increased markedly on two occasions during the evolution of primates and ruminants. To investigate the evo- lutionary pattern of growth hormone receptor (GHR), we sequenced the extracellular domain of GHR genes from four primate species. Our results suggested that GHR in mammal also shows an episodic evolutionary pattern, which is consis- tent with that observed in pituitary growth hormone. Fur- ther analysis suggested that this pattern of rapid evolution observed in primates and ruminants is likely the result of coevolution between pituitary growth hormone and its re- ceptor.
文摘Due to its specific characteristics, such as ma-ternal inheritance and absence of recombination, each mtDNA belongs to certain monophyletic clade in the rooted mtDNA tree (haplogroup) according to the mutations it harbors. Rare mutation (excluding parallel mutation) occur-ring at multiple times in different haplogroups could thus be a potential reading error according to the mtDNA phylogeny. This experience has been widely used in double-checking the credibility of the rare mutations in human mtDNA sequences. However, no test has been performed so far for the feasibility of applying this strategy to the rare insertion/deletion (indel) events in mtDNA sequences. In this study, we attempted to relate the rare indels in mtDNAs to their haplogroup status in a total of 2352 individuals from 50 populations in China. Our results show that the insertion of A at position 16259 is restricted to a subclade of haplogroup C and can be verified. The other indel polymorphisms, which occur in the repeat of the deleted or inserted nucleotide(s), may not be distin-guished from phantom mutations from a phylogenetic point of view. Independently and multiply sequencing the frag-ment with the indel is the best and the most reliable way for confirmation.
基金supported by the National Natural Science Foundation of China(Grant Nos.30021004&30430110)Yunnan Bureau of Science and Technology,and the Chinese Academy of Sciences
文摘In the present study, we obtained exon 2―5 of prolactin (PRL) gene from four primate species by PCR and sequencing. Adding other genes available in GenBank, we calculate amino acid substitution rates for prolactin gene in primate. Comparison of nonsynonymous substitution rate to synonymous substitution rate ratios shows no evidence of positive selection for any lineage of primate prolactin gene. According to this and the facts that (i) no sites under positive selection are inferred by using maximum-likelihood method; (ii) among 32 amino acid replacement that occurred along the rapid evolutionary phase, only two are included in the 40 functionally important residues, indicating that amino acid replacement tends to occur in those functionally unimportant residues; (iii) partial of prolactin function is replaced by pla-cental lactogen in primate at the rapid evolutionary phase of prolactin gene, we thus deem that it is relaxation of purifying selection to some extent rather than positive selection that enforces the rapid evolution of primate prolactin gene.
