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991.
Jiang B  Yap MK  Leung KH  Ng PW  Fung WY  Lam WW  Gu YS  Yip SP 《PloS one》2011,6(5):e19587

Background

The paired box 6 (PAX6) gene is considered as a master gene for eye development. Linkage of myopia to the PAX6 region on chromosome 11p13 was shown in several studies, but the results for association between myopia and PAX6 were inconsistent so far.

Methodology/Principal Findings

We genotyped 16 single nucleotide polymorphisms (SNPs) in the PAX6 gene and its regulatory regions in an initial study for 300 high myopia cases and 300 controls (Group 1), and successfully replicated the positive results with another independent group of 299 high myopia cases and 299 controls (Group 2). Five SNPs were genotyped in the replication study. The spherical equivalent of subjects with high myopia was ≤−8.0 dioptres. The PLINK package was used for genetic data analysis. No association was found between each of the SNPs and high myopia. However, exhaustive sliding-window haplotype analysis highlighted an important role for rs12421026 because haplotypes containing this SNP were found to be associated with high myopia. The most significant results were given by the 4-SNP haplotype window consisting of rs2071754, rs3026393, rs1506 and rs12421026 (P = 3.54×10−10, 4.06×10−11 and 1.56×10−18 for Group 1, Group 2 and Combined Group, respectively) and the 3-SNP haplotype window composed of rs3026393, rs1506 and rs12421026 (P = 5.48×10−10, 7.93×10−12 and 6.28×10−23 for the three respective groups). The results remained significant after correction for multiple comparisons by permutations. The associated haplotyes found in a previous study were also successfully replicated in this study.

Conclusions/Significance

PAX6 haplotypes are associated with susceptibility to the development of high myopia in Chinese. The PAX6 locus plays a role in high myopia.  相似文献   
992.
In mid-May 2022, pink salmon Oncorhynchus gorbuscha smolts were caught in the rivers Botnsá, Grímsá, and Langá in Iceland. This observation provides the first evidence of successful spawning and the completion of the freshwater phase of the life cycle in Icelandic rivers. It is the most western record of O. gorbuscha smolts in Europe, further west than Russia, Norway, and the UK. Smolts originating from Iceland potentially support the recruitment of this species in the North Atlantic and may lead to the establishment of a self-sustaining population in Iceland.  相似文献   
993.
Abstract.  1. The codling moth Cydia pomonella , one of the most important pest insects of apple fruit orchards worldwide, is regarded as a 'sedentary' insect, but the natural populations consist of both mobile and sedentary genotypes that display different dispersal capacity in the field. The current study investigated whether there is a fitness consequence of being mobile in this species by comparing two strains with contrasting levels of mobility obtained through bi-directional selection.
2. Female moths of the sedentary strain were significantly larger, laid more eggs during their lifespan, and both male and female moths of this strain lived longer, when compared with the mobile strain.
3. The age-specific fecundity of female moths from the sedentary strain was significantly greater, in particular between 3 and 5 days after emergence when the peaks of both oviposition and flight capacity occur, relative to the mobile moths, thereby leading to a greater reproductive function.
4. These differences resulted in different demographic parameters between the two strains. The sedentary strain had a significantly greater net reproductive rate ( R o ) and a higher intrinsic rate of natural increase ( r m ), although the generation time ( T ) was similar, hence requiring a shorter time to double the population size, in comparison to the mobile strain.
5. This study provides empirical evidence for the cost of being mobile in C. pomonella . Trade-offs between mobility and fitness might have contributed to the existence of genetic variance for dispersal behaviour in the natural populations and the maintenance of relative sedentariness in the species.  相似文献   
994.
Gossypol is an antifertility agent which inhibits steroidogenesis in both sexes. The present study investigated the binding of gossypol in organelles of cultured bovine luteal cell to elucidate its inhibitory site of action in steroid biosynthesis. Cultured bovine luteal cells were incubated with 3H-gossypol (4.3 or 2.15 microM) for 3 hours. At the end of treatment, cultured bovine luteal cells were harvested, homogenized and centrifuged for organelle preparation. The radioactivity of gossypol was measured in each subcellular fraction. The cell membrane fraction has the highest binding capacity for gossypol, and the majority of gossypol was located in the particulate fractions. Results of the present study provide information in understanding the regulatory mechanism of gossypol on antisteroidogenic and/or toxic effects in cultured bovine luteal cells.  相似文献   
995.
996.
997.
Oct4 plays an essential role in maintaining the inner cell mass and pluripotence of embryonic stem (ES) cells. The expression of Oct4 is regulated by the proximal enhancer and promoter in the epiblast and by the distal enhancer and promoter at all other stages in the pluripotent cell lineage. Here we report that the orphan nuclear receptor LRH-1, which is expressed in undifferentiated ES cells, can bind to SF-1 response elements in the proximal promoter and proximal enhancer of the Oct4 gene and activate Oct4 reporter gene expression. LRH-1 is colocalized with Oct4 in the inner cell mass and the epiblast of embryos at early developmental stages. Disruption of the LRH-1 gene results in loss of Oct4 expression at the epiblast stage and early embryonic death. Using LRH-1(-/-) ES cells, we also show that LRH-1 is required to maintain Oct4 expression at early differentiation time points. In vitro and in vivo results show that LRH-1 plays an essential role in the maintenance of Oct4 expression in ES cells at the epiblast stage of embryonic development, thereby maintaining pluripotence at this crucial developmental stage prior to segregation of the primordial germ cell lineage at gastrulation.  相似文献   
998.
Li X  Ji C  Gu J  Xu J  Jin Z  Sun L  Zou X  Lin Y  Sun R  Wang P  Gu S  Mao Y 《Molecular biology reports》2005,32(2):127-131
Triple-A syndrome (MIM 231550; also known as Allgrove syndrome) is an autosomal recessive disorder characterized by adrenocorticotropin hormone (ACTH)-resistant adrenal insufficiency, achalasia of the oesophageal cardia and alacrima. Much initial molecular analysis supported that Triple-A syndrome was caused by mutations in AAAS, a WD-repeat protein gene. Here we report cloning and characterization of a novel splice variant of human AAAS, which we named AAAS-v2, which is located on the human chromosome 12p13. The cDNA is 1703bp, encoding a 513-amino acid polypeptide, which contains three WD40 domains, one less than the original which we called AAAS-v1 (Gen Bank: NM_015665.3). RT-PCR analysis in our work revealed that AAAS-v2 and AAAS-v1 were ubiquitously detected in human multiple tissue cDNA (MTC) panels (CLONTECH).The nucleotide sequence reported in this paper has been submitted to GenBank under accession number AY237818.Xin Li: These two authors contributed equally to this paper.Chaoneng Ji: These two authors contributed equally to this paper.  相似文献   
999.
Analysis of synonymous codon usage in H5N1 virus and other influenza A viruses   总被引:11,自引:0,他引:11  
Zhou T  Gu W  Ma J  Sun X  Lu Z 《Bio Systems》2005,81(1):77-86
In this study, we calculated the codon usage bias in H5N1 virus and performed a comparative analysis of synonymous codon usage patterns in H5N1 virus, five other evolutionary related influenza A viruses and a influenza B virus. Codon usage bias in H5N1 genome is a little slight, which is mainly determined by the base compositions on the third codon position. By comparing synonymous codon usage patterns in different viruses, we observed that the codon usage pattern of H5N1 virus is similar with other influenza A viruses, but not influenza B virus, and the synonymous codon usage in influenza A virus genes is phylogenetically conservative, but not strain-specific. Synonymous codon usage in genes encoded by different influenza A viruses is genus conservative. Compositional constraints could explain most of the variation of synonymous codon usage among these virus genes, while gene function is also correlated to synonymous codon usages to a certain extent. However, translational selection and gene length have no effect on the variations of synonymous codon usage in these virus genes.  相似文献   
1000.
Phosphine (PH3) was monitored in the Taihu Lake in China by a GC/NPD method, coupled with cryo-trapping enrichment technology. Results showed that PH3 was universally detected in sediments, lake water and atmosphere of the Taihu Lake area. Total phosphorus (TPs) and fractions of different phosphorus species in lake sediments were separately measured as dissolved phosphate (DP), phosphorus bound to aluminum (Al-P), iron (Fe-P) and calcium (Ca-P), occluded phosphorus (OP), and organic phosphorus (Org-P) by sequential chemical extraction. High PH3 levels were correlated with high TPs values in sediments and with eutrophication at different sites. In addition, a positive linear correlation equation was obtained between the concentrations of PH3 in lake sediments and of the phosphorus fractions. The resulting multiple linear regression equation is PH3 = −165 + 63.3 DP + 0.736 Al-P + 2.33 Ca-P + 2.29 Org-P. The flux of PH3 across the sediment–water interface was estimated from sediment core incubation in May and October 2002. The annual average sediment–water flux of PH3 was estimated at ca. 0.0138±0.005 pg dm−2 h−1, the average yearly emission value of PH3 from Taihu Lake sediments to water was calculated to be 28.3±10.2 g year−1, which causes a water PH3 concentration of up to 0.178±0.064 pmol dm−3. The real importance of PH3 could be higher, because PH3 could be consumed in the oxic sediment–water boundary layer and in the water column. Spatial and temporal distributions of total phosphorus (TPw) and chlorophyll a (Chl-a) in the water column of Taihu Lake were measured over the study period. Higher water PH3 has also been found where the TPw content was high. Similarly, high Chl-a was consistent with higher water PH3. Positive relationships between PH3 and TPw (average R2 = 0.47±0.26) and Chl-a (average R2 = 0.23±0.31) were observed in Taihu Lake water.  相似文献   
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