Molecular Cloning and Bioinformatics Analysis of DQA Gene from Mink (Neovison vison).

Zhaobin Fan,Houfeng Zhang,Zhenxing Yu,Min Rong,Peihong Jiang,Dongmei Meng,Lili Jiang

doi:10.3390/ijms20051037

Abstract

In the present study, we cloned, sequenced, and explored the structural and functional characteristics of the major histocompatibility complex (MHC)-DQA gene from mink (Neovison vison) for the first time. The full-length sequence of DQA gene was 1147-bp-long, contained a coding region of 768-bp, which was predicted to encoding 255 amino acid residues. The comparison between DQA from mink (Neovison vison) and other MHC-DQA molecules from different animal species showed that nucleotide and encoded amino acid sequences of the mink DQA gene exhibited high similarity with the ferret (Mustela pulourius furo). Phylogenetic analysis revealed that mink (Neovison vison) DQA is grouped with that of ferret (Mustela pulourius furo). The cloned sequence contained a 23-amino acid NH2-terminal signal sequence with the signal peptide cutting site located in amino acids 23–24, and had three Asn-Xaa-Ser/Thr sequons. Three cysteine residues were also identified (Cys-85, Cys-121, and Cys-138). The 218 to 240 amino acids were predicted to be the transmembrane domains. The prediction of the secondary structure revealed three α-helixes and fourteen β-sheets in Neovison vison DQA protein, while random coil was a major pattern. In this study, the whole CDS sequence of Neovison vison DQA gene was successfully cloned, which was valuable for exploring the function and antiviral molecular mechanisms underlying the molecule. The findings of the present study have laid the foundation for the disease resistance and breeding of mink.

Highlights

The major histocompatibility complex (MHC) is a chromosomal region consisting of a group of closely linked loci
Due to the polygenic characteristics, MHC was divided into MHC class I, II, and III genes according to the differences in the structure, tissue distribution, and function of the coding molecules [4]
The amplicons were obtained by PCR amplification of the complementary DNA (cDNA) with gene-specific primers encoding the DQA gene (Figure 1)

Summary

Introduction

The major histocompatibility complex (MHC) is a chromosomal region consisting of a group of closely linked loci. It binds to specific epitopes, which is the key to triggering the immune system to attack the virus-infected cell through the proteins involved in the immune response of the body [1,2,3]. The class II genes of MHC encoded for α and β chains of DR and DQ dimer molecules, which present antigenic peptides to the helper T cells and was considered as a candidate gene for animal disease-resistant breeding [5,6,7]. Due to the central role of DQA gene in the vertebrate immune system, it is presumed that one of the main selective pressures promoting MHC diversity gives rise to the susceptibility or resistance against infectious diseases and autoimmune disorders [11,12]

Methods

Results

Conclusion