Development of Genomic Tools for Cucumber, Cucumis sativus L.

Abstract

Genomics tools have become increasingly varied and valuable for crop improvement. While several species have been targeted for concerted genomic efforts, the majority of horticultural species have received limited attention. Despite the wide variety of important cucurbit crop species, the Cucurbitaceae family has had minimal effort. We have initiated projects to develop genomic tools for cucumber, Cucumis sativus L. Efforts include production of cDNA, yeast two-hybrid, and genomic libraries, and development of an EST database and website for cucumber genomics. Sequences of cucumber leaf ESTs so far indicate that the cDNA library is of high quality and has modest redundancy. Distribution of sequences, as nominally predicted from GeneBank BLAST analysis, indicates that expressed genes fall in the following general categories: photosynthesis (21%), DNA/RNA/protein synthesis (20%), metabolism (15%), signaling (5%), other (16%), and unknown proteins (23%). Cucumber sequence data have been deposited into GenBank and are available on the Michigan State Univ. website (http://genomics.msu.edu/cucumberdb). The yeast two-hybrid library has been successfully used to identify and characterize several genes based on interaction with key proteins of interest, including genes interacting with viral replicases and poly(A) binding protein. The genomic library has been verified to be of high quality and has been used to identify clones of interest.