ABSTRACT
The Sox (SRY-related high-mobility-group box) family of genes shares a conserved HMG box and is involved in a diverse range of developmental processes and sex determination in vertebrates. Twenty Sox genes are present in the genomes of humans and mice, but far less is known about the Sox gene family in reptiles. Using two pairs of highly degenerate primers designed from a multiple alignment of Sox amino acid sequences in several species, different positive clones were obtained from male and female Eremias multiocellata, a viviparous lizard which is subject to TSD (temperature-dependent sex determination). These clones were sequenced and identified. They are members of the SoxB (Sox2, Sox14), SoxC (Sox11, Sox12) and SoxE (Sox9a, Sox9b, Sox10) groups. No sex-specific differences were observed. Based on the amino acid sequence similarities, the phylogenetic analysis was carried out and these genes clustered with their orthologues. In addition, we found the gene duplication in E. multiocellata, it may be a mechanism to produce new functional genes.
Subject(s)
Lizards/genetics , SOXB1 Transcription Factors/genetics , SOXC Transcription Factors/genetics , SOXE Transcription Factors/genetics , Amino Acid Sequence , Animals , Base Sequence , Female , HMG-Box Domains/genetics , Humans , Male , Mice , Molecular Sequence Data , Phylogeny , SOXB1 Transcription Factors/isolation & purification , SOXC Transcription Factors/isolation & purification , SOXE Transcription Factors/isolation & purification , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sex Determination ProcessesABSTRACT
To investigate the function and evolutionary origin of the SOXE subgroup, we amplified the genomic DNA of Misgurnus anguillicaudatus using a pair of degenerate primers. Using RACE, we obtained two versions of Sox8 (MaSox8a and MaSox8b) from M. anguillicaudatus. The overall sequence identity of the deduced amino acids from the two genes was 54.38%, with only one amino acid change in the high-mobility group domain. Southern blotting and evidence from the phylogenetic tree provided further proof for the existence of two Sox8 genes at the genomic level. This is the first evidence of two distinct Sox8 genes in Cypriniformes. Semi-quantitative and real-time quantitative PCR assays showed the expression trend of the genes was opposite in early embryonic development, and both were expressed ubiquitously in several adult tissues. The similar expression patterns indicated that MaSox8a and MaSox8b have possible overlapping functions.