1 USDA-ARS, Crop Production and Pest Control Research Unit, Department of Agronomy, Purdue University, West Lafayette, IN 47907-1155 USA
2 USDA-ARS, Crop Production and Pest Control Research Unit, Department of Entomology, Purdue University, West Lafayette, IN 47907-1155 USA
3 USDA-ARS, Crop Production and Pest Control Research Unit, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907-1155 USA
As part of a project to analyze the functional genomics of pest resistance in wheat, an EST database
was constructed from the cultivar P29. Random cDNA clones from a non-normalized library made
from nine-day old seedling tissue were sequenced at the Purdue University Genome Facility.
Blast analyses of the first 254 ESTs from the database revealed abundant messages for genes
involved in photosynthesis, as well as more unusual sequences. Approximately 25% of the ESTs
corresponded to rubisco, 5% to rubisco activase, 10% to chlorophyl a/b binding proteins and 7%
to photosystem I and II sequences. Among the remaining 132 ESTs, 76 were tentatively identified
by similarity to previously cloned genes in the Blast searches. At least 60 different genes were
identified in total. Wheat homologs were present already in GenBank for only nine of these genes.
Two sequences were similar to previous wheat entries in GenBank, but had higher Blast hits with
accessions from other species. No corresponding wheat entries were present in GenBank for the
remaining 49 genes. Enzymes involved in glycolysis, gluconeogenesis, carbohydrate and fatty acid
metabolism, nucleotide and protein biosynthesis were identified. ESTs for structural proteins included
histone H3 and beta-tubulin. In addition, a Cf2-like EST was identified that showed high derived
amino acid similarity to both an Arabidopsis and a barley sequence. Cf2 conditions resistance to
the fungus Cladosporium fulvum in tomato but its function in wheat remains unknown.