Phylogenetic Analysis Of SERPINA Subfamily And SERPINA3n Expression In Microtus Fortis

SERPINs (serine protease inhibitors) is a widely distributed protease inhibitors superfamily, and some members play an important regulatory role in physiological and pathological processes in the body, especially the immune regulations and inflammation responses. And other members' function need further study. Active evolution and significant differentiation is the basis for different biological functions. This study use evolutionary analysis, explain the evolution law of SERPIN, pointed out the goals and directions of the further study of the functions of SERPIN family members.Schistosomiasis is worldwide distributed, and is one of the most serious hazards of zoonotic parasitic diseases. The human or mouse infected with Schistosoma japonicum result a low cellular immune status. However, Microtus fortis is the only mammal that has natural anti-schistosomiasis abilities. Existing research results show that some members of SERPIN participate in the course of against Schistosoma japonicum infection. This experiment use bioinformatics, and RT-PCR, to determine which members of Microtus fortis SERPIN family associated with natuaral resistance to Schistosoma japonicum, and helping to clarify the molecular mechanism of Microtus fortis against Schistosoma japonicum infection. We use the knowned SERPINs and their conserved regions BLAST genome database, phyligenetic analyze the representative species' SERPINs as:Gallus gallus, Mus musculus, Pan troglodytes and Homo sapiens. The results show that A, B subfamily's evolution is very active. The further phyligenetic analysis of mammals SERPINA subfamily shows that the evolutionary of Rodentia A3 subfamily is extremely active. And the evolution's activity is closely related to the function's diversity.Through designing SERPIN primers from conserved regions in rats and mice, amplified 5 members of Microtus fortis SERPINA subfamily genes'reactive center loop(RCL) sequences and SERPINA3n's ORF. The evolution and sequence structure analysis shows that the Microtus fortis SERPINA3n gene differs from rat and mouse orthologous, especially in the ractive site loop, P1 residue, the specific protease hydrolysis site. As structrue determines function, suggests Microtus fortis SERPINA3n have a different suppression function.In order to understand the Microtus fortis SERPINA3n's role in the actions of anti-Schistosoma japonicum. Extracted total RNA from liver tissues of Microtus fortis and mouse that infected with Schistosoma japonicum, as:0 days,7 days after and 12 days after infection, using RT-PCR detecting the differences of SERPINA3n subfamily in gene expression. The results show that SERPINA3n gene both down-regulated in Microtus fortis and mice, and there is difference between them. In conclusion, the evolutionary of Rodentia A3 subfamily is extremely active, obviously its members have significant functional differentiation, and needs further study. Microtus fortis SERPINA3n gene's RCL obviously differs from rat and mouse, and have a different reaction specificity. Microtus fortis SERPINA3n gene evidently down-regulated after infection, may play an immune suppression role in the course of anti-Schistosoma japonicum.