Construction of Suppression Subtractive Hybridization cDNA Library of Sweetpotato Induced by Ditylenchus destructor and Analysis of Its Expressed Sequence Tags
Abstract:Abstract: A suppression subtractive hybridization (SSH) cDNA library was constructed by using the storage roots of sweetpotato (Ipomoea batatas (L.) Lam.) cv. Lushu 3 resistant to sweetpotato stem nematode. A total of 1379 positive clones were screened and sequenced, and then clustered by CAP3 software, 185 unique expressed sequence tags (ESTs) were obtained. After blasted in Genbank, innotated GO and matched metabolism pathway in KEGG by Blast2Go software, it was found that 151 unigenes, accounting for 81.6% of all the unigenes, showed high homology with the function known genes or ESTs, which were related to energy metabolism, signal transduction, defense response and protein synthesis metabolism. Results of analysis on the function known genes suggest that mitogen-activated protein kinase, serine/threonine protein kinase, catalase, chitinase and glucanase may involve in the process of resistance reaction to sweetpotato stem nematode. Four defense-related genes wereconfirmed to have different expression profile at different times after inoculated with the stem nematodes by real-time quantitative reverse-transcriptase PCR.