Cloning and characterization of an HOG1 MAPK homologous gene CgHOG1 from Candida glycerinogenes

Abstract:

Abstract:［Objective］This study was aimed to obtain a key gene of osmo-adaptation and glycerol synthesis regulation in Candida glycerinogenes，namely mitogen-activated protein kinase HOG1 gene (CgHOG1)，and to verify its function of osmo-regulation.［Methods］The gene CgHOG1 was amplified by Degenerate PCR and Self-Formed Adaptor PCR from the C. glycerinogenes genome and the bioinformatic analysis of CgHOG1 gene was conducted. The CgHOG1 gene was transformed in Saccharomyces cerevisiae hog1Δ null mutant and its salt tolerance characteristics was investigated.［Results］The gene CgHOG1 encoded a protein of 387 amino acids with an open reading frame of 1164 bp and the amino acid sequence showed 86% identity to Hog1p of Ogataea parapolymorpha． Heterologous expression of CgHOG1 gene in S.cerevisiae W303 hog1Δ null mutant showed an increase in salt tolerance and glycerol production compared to S.cerevisiae W303 hog1Δ null mutant.［Conclusion］The CgHOG1 obtained in this study is a novel HOG1 gene from C. glycerinogenes，which plays an essential role in the yeast hyperosmotic response and glycerol synthesis. We supplied a new gene for the osmo-adaptation mechanism in C. glycerinogenes and molecular modification of the salt-tolerant and droughtresistant crops.

Key words:Keywords: Mitogen activated protein kinase，Candida glycerinogenes，HOG1，Osmo-regulation