Cloning of Mulberry MuPR1a Gene and Activity Assay of Its Promoter

Pathogenesis-related proteins( PR) play a key role in plant defense response against pathogens. In this study,mulberry pathogenesis-related protein gene MuPR1a( GenBank accession No. KC453993) was cloned from mulberry leaves. The full length of its coding region is 516 bp and encodes 171 amino acids. MuPR1a possesses one typical secretory signal peptide and multiple conserved domains of PR proteins. Sequence comparison analysis showed that MuPR1a had very high sequence identity with RP1a protein from other plants. The promoter of MuPR1a gene was cloned using TailPCR technique and was designated as MPRp( GenBank accession No. KC849423). MPRp contains cis-acting elements CAAT-box,TATA-box,TCA-element,and GCC box,which are necessary for the normal transcriptional initiation. The activity of MPRp was investigated by means of Agrobacterium-mediated transient expression in tobacco leaves,and the result indicated that MPRp could drive the expression of reporter gene and could be induced upon infection of pathogen.