Cloning and molecular characteristics of Datong yak's LF gene.

A cDNA sequence containing coding region of LF gene of yak was cloned by RT-PCR and compared to corresponding sequences of cow.The sequences were analysed in yak and other species.Using online biological softwares,the structure and properties of LF protein of yak were predicted.The 2 344 bp cDNA of LF gene of yak was cloned,and the length of coding region of LF gene was 2 124 bp,encoding 708 amino acids.There were 15 mutations in the cDNA between yak and cow.There was high homology of LF protein among different species.The evolutionary tree of all species complies with laws of evolution.There was 36.0% alpha helix,22.4% extended strand,31.1% beta turn,12.9% random coil in LF protein of yak.Homogenous 3D model of LF by predict showed that LF protein formed two similar and symmetrical leaves,namely N-leaf and C-leaf connected by an alpha helix impressionable to proteinase,and LF protein presented "two-folium-ginkgo-shaped" structure.