Gene expression and EST analyses of Ustilago maydis germinating teliospores.
Ustilago maydis grows in its host Zea mays eliciting the formation of obvious tumors that are full of black teliospores. Teliospores are thick-walled, dormant, diploid cells that have evolved for dispersal and survival of the pathogen. Their germination leads to new rounds of infection and is temporally linked to meiosis. We are investigating gene expression during teliospore germination to gain insight into the control of this process. Here we identify genes expressed through creation of an expressed sequence tag (EST) library. We generated 2871 ESTs that are assembled into 1293 contiguous sequences. Based upon a blast search similarity cutoff of E < or =10(-5) 38% of all contigs were orphans while 62% showed similarity to sequences in the protein database. Analyses of blast searches were used to functionally classify genes. Northern hybridizations using specific cDNA clones reveal a relative level of expression consistent with the number of sequences per contig. Identified genes and expression information provide a base for genome annotation of U. maydis and further investigation of teliospore germination and pathogenesis.
Sacadura
Nuno T
NT
Department of Botany, University of Toronto at Mississauga, 3359 Mississauga Road North, Mississauga, Ont., Canada L5L 1C6.
Saville
Barry J
BJ
D015152:Blotting, Northern; D018076:DNA, Complementary / Q000032:analysis / Q000235:genetics; D016208:Databases, Factual; D020224:Expressed Sequence Tags; D015870:Gene Expression; D015966:Gene Expression Regulation, Fungal; D015723:Gene Library; D005800:Genes, Fungal / Q000235:genetics; D008969:Molecular Sequence Data; D013172:Spores, Fungal / Q000235:genetics* / Q000378:metabolism; D014588:Ustilago / Q000201:enzymology / Q000235:genetics*; D003313:Zea mays / Q000382:microbiology
D018076:DNA, Complementary