The RACE amplifying and sequence analyzing of secreted aspartic pro- teinase gene SA76 of Trichoderma harzianum

摘要

Total RNA was isolated from mycelium of T. harzianum by Total RNA extraction kit, and two clear bands of rRNA (28S and 18S) were observed in agarose electrophoresis. By joining the 3'end sequence with the known SA76 EST from cDNA library of T. harzianum, a full-length cDNA sequence of 2019bp was obtained, whose open reading frame contained 1593bp, a stop codon TAA, a 5'untranslated region (5'UTR) of 266bp, a 3'untranslated region (3'UTR) of 201bp, and poly (A) 29 encoded a protein of 530 amino acids, had a signal peptide. T. harzianum shared 53% identity of secreted aspartic proteinase gene with G. zeae, 37% with N. crassa and 36% with C. globosum. The full-length cDNA sequence of secreted aspartic proteinase gene from T. harzianum was cloned for the first time by using BD SMART RACE technique, which provides a foundation to obtain and validate functional genes of T. harzianum.