Cloning And Sequence Analysis Of Sox HMG-box And Dmrt DM Domain From Andrias Davidianus

Andrias davidianus is rare and valuable species in China, with the continuous deterioration of the ecological environment, the population dropped sharply. In order to increase its population, many research workers carried out a lot of its research, but on its genetic material was very little. Sox gene family and Dmrt gene family are two of the gene families which participate in the development process of animal. The Sox gene family is characterized by a highly conserved DNA-binding and bending domain known as an HMG box. They play important roles in embryonic development, sex differentiation and organism formation. The DMRT genes constitute a new gene family related to sex-determination.They were isolated by virtue of its homology to the double sex gene from Drosophila,Mab-3 from Citisaenorhabd elegan and human DMRT, which encode putative transcription factors with a conserved DM domain.that is thought to bind specific DNA sequence in form of zinic finger. The characteristic and function of Dmrt genes were also discussed in the review.This research cloning the Sox HMG-box and Dmrt DM domain of A. davidianus through experimental technique of molecular biology, and then analysis the bioinformatics of them. This study presented evidence of sex determination genes in the ancient amphibian species of A.davidianus for the first time, which provides sequence information for further molecular investigation and gene function.1.Degenerate primers designed from a highly conserved HMG-box region of multiple aligned Sox gene sequences, was successfully used for the amplification of the HMG-box region of the Sox gene from A.davidianus by polymerase chain reaction (PCR) technique. A DNA fragment was obtained by PCR using A.davidianus genomic DNA as a template. Homology searching against databases confirmed its identity as HMG-box region of the Sox gene from A.davidianus. The sequence comparison analysis showed that the A.davidianus HMG-box shared high sequence similarity with HMG-box region of Sox genes from Oryzias latipes (79%),Xenopus tropicalis (83%), Gallus gallus (88%), Musculust (91%), Canis lupus(91%)and Homo sapiens (90%) at DNA level;and its amino acid sequence is 81%,89%,92%,92%,92%,92% respectively.2.Degenerate primers designed from a highly conserved DM region of multiple aligned Dmrt gene sequences, was successfully used for the amplification of the DM domain of the Dmrt gene from A.davidianus by polymerase chain reaction (PCR) technique. A DNA fragment was obtained by PCR using A. davidianus genomic DNA as a template. Homology searching against databases confirmed its identity as DM region of the Dmrt gene from A.davidianus. The sequence comparison analysis showed that the Andrias DM shared high sequence similarity with DM of Dmrt genes from Macaca mulatta (91%), Oryzias latipes (92%), Homo sapiens (92%), Mus musculus (89%), Rana rugosa (86%) and Bos taurus (91%) at DNA level, but its amino acid sequence remained at a similar level with all other DMs (≈91%).