unigene catalogue of 5700 expressed genes in cassava

• Published in: Plant molecular biology 2004-11, Vol.56 (4), p.541-554
• Main Authors: Lopez, C, Jorge, V, Piegu, B, Mba, C, Cortes, D, Restrepo, S, Soto, M, Laudie, M, Berger, C, Cooke, R
• Format: Article
• Language: English
• Subjects: agronomic traits; bacterial diseases of plants; Biosynthesis; blight; carbohydrate content; Cassava; cDNA libraries; clones; Cluster Analysis; complementary DNA; Cultivars; disease resistance; DNA, Complementary; DNA, Complementary - chemistry; DNA, Complementary - genetics; Economic importance; Expressed Sequence Tags; gene expression; Gene Expression Regulation, Plant; Gene Library; genes; Genes, Plant; Genes, Plant - genetics; Genetics; Libraries; Life Sciences; Manihot; Manihot - genetics; Manihot - metabolism; Manihot - microbiology; Manihot esculenta; Molecular Sequence Data; Multigene Family; Multigene Family - genetics; nucleotide sequences; Pathogens; Plant Diseases; Plant Diseases - genetics; Plant Diseases - microbiology; plant pathogenic bacteria; Plant tissues; Plants genetics; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Starch; Starch - biosynthesis; Xanthomonas; Xanthomonas - growth & development; Xanthomonas axonopodis; Xanthomonas axonopodis pv. manihotis
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/s11103-004-0123-4

Two economically important characters, starch content and cassava bacterial blight resistance, were targeted to generate a large collection of cassava ESTs. Two libraries were constructed from cassava root tissues of varieties with high and low starch contents. Other libraries were constructed from plant tissues challenged by the pathogen Xanthomonas axonopodis pv.manihotis. We report here the single pass sequencing of 11,954 cDNA clones from the 5' ends, including 111 from the 3' ends. Cluster analysis permitted the identification of a unigene set of 5,700 sequences. Sequence analyses permitted the assignment of a putative functional category for 37% of sequences whereas approximately 16% sequences did not show any significant similarity with other proteins present in the database and therefore can be considered as cassava specific genes. A group of genes belonging to a large multigene family was identified. We characterize a set of genes detected only in infected libraries putatively involved in the defense response to pathogen infection. By comparing two libraries obtained from cultivars contrasting in their starch content a group of genes associated to starch biosynthesis and differentially expressed was identified. This is the first large cassava EST resource developed today and publicly available thus making a significant contribution to genomic knowledge of cassava.