title: Characterization and tissue distribution of Lhx9 and Lhx9α in Chinese giant salamander Andrias davidianus.
abstract: Lhx9 is an LIM (named for the first three proteins in which the domain was found, Lin-11, Isl1 and Mec-3) homeodomain protein involved in development and differentiation of the gonad. In this study, we isolated the full-length Lhx9 and Lhx9α from Andrias davidianus, detected the tissue distribution and analysed the methylation of the promoters. We identified Lhx9 of 1411 bp and Lhx9α of 1153-bp length, differing in the 3'-flanking region, encoding 399 and 330 amino acids, respectively. The Lhx9 gene was detected primarily in liver, ovary and heart with moderate expression in brain, pituitary, intestine and spleen, and low expression in the remaining examined tissues, while Lhx9α expression was high in heart, pituitary and liver, and low in spleen and stomach. Significantly higher Lhx9 expression was observed in ovary than in testis, with no differences in Lhx9α expression between testis and ovary observed. Bisulphite sequencing revealed significantly higher methylation in testis compared to ovary. The methylation level of CpG sites -733, -673, -615 and -594 exhibited significantly higher levels in testis than in ovary, which was negatively correlated with Lhx9 expression. The methylation and expression patterns suggested that promoter methylation suppressed expression of Lhx9 in A. davidianus.
authors.affiliation: Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Science, Wudayuan First Road 8, 430223 Wuhan, People's Republic of China.xhb@yfi.ac.cn.
authors.forename: Qiaomu
authors.initials: Q
authors.lastname: Hu
authors.forename: Haifeng
authors.initials: H
authors.lastname: Tian
authors.forename: Yan
authors.initials: Y
authors.lastname: Meng
authors.forename: Hanbing
authors.initials: H
authors.lastname: Xiao
mesh_terms: D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D019175:DNA Methylation; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D060850:LIM-Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D008099:Liver / Q000254:growth & development / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism; D010053:Ovary / Q000254:growth & development / Q000378:metabolism*; D010902:Pituitary Gland / Q000254:growth & development / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012741:Sexual Maturation / Q000235:genetics*; D013154:Spleen / Q000254:growth & development / Q000378:metabolism; D013270:Stomach / Q000254:growth & development; D013737:Testis / Q000254:growth & development / Q000378:metabolism*; D014562:Caudata / Q000235:genetics* / Q000254:growth & development
chemical_list: D029845:Amphibian Proteins; D060850:LIM-Homeodomain Proteins; D020033:Protein Isoforms