Analysis of EST Libraries from Leptosphaeria maculans and Blackleg Infected Brassica napus

Abstract

The ascomycete Leptosphaeria maculans is the causal agent of blackleg of crucifers. cDNA libraries were constructed and partially sequenced to increase the amount of L. maculans sequence data available and to survey genes expressed during pathogenesis. Two libraries were built, one from cultured mycelia (LM) and one from Brassica napus leaf tissue infected with L. maculans (ILS). A total of 741 expressed sequence tags (ESTs) were obtained from the LM library, and 1284 were obtained from the ILS library. The vast majority of the ESTs obtained from the ILS library appear to originate from B. napus (70-81% depending on the identification method). Various methods for determining sequence origin in mixed libraries were compared. cDNAs with a putative role in pathogenesis were identified from the ILS library. These and other cDNAs of interest from the LM library are discussed.