We amplified the 197 bp HMG box sequence by using Polymerase Chain Reaction (PCR) with primers according to the known SRY sequence from male raccoon genomic DNA, and then cloned and sequenced. The nucleic acid and amino acid sequence comparison between raccoon and other mammals revealed high conservation of the SRY HMG box in mammals (about 80%), which implied that the DNA binding activity was crucial to mediate the action of SRY in sex determination. The variation of raccoon HMG box sequence mainly occurred on purine by replacement and missense mutation, which implicated that only the HMG box protein with advanced structure had efficient activity. The homology and difference between mammals HMG box was accorded to the evolution systematic tree.
The full coding region of brain derived neurotrophic factor (BDNF) gene from Tylototriton taliangensis genome was amplified by PCR with the primers designed according to the sequence of human BDNF gene. Sequence analysis shows that the coding region has 744 bp in length and is highly homologous with that of mammals and aves. The homology of deduced BDNF protein sequence is about 90% with that of human. It is the first time to amplify and analyze BDNF gene from the newt genome, which will provide useful information for protecting and studying the severely endangered species. Fig1,Tab1,Ref
大多数两栖类物种的染色体较长大,数目较少,是细胞遗传学,细胞工程学,发育生物学等研究的好材料。两栖类在进化地位上介于水生脊椎动物和陆生脊椎动物之间,因此,进行两栖类染色体的比较研究,对于探讨和认识动物的系统演化具有一定的意义。 有关无尾两栖类染色体组型的研究,国外已有不少报道(Benirschke et al.,1973;Bogart,1968;Guillemnin,1967;Haertel,1974;Schmid,1978a,1978b),国内吴政安(1978,1981;吴政安等,1980,1981)李树深等(1981)作了几种蛙的染色体组型研究。
