The maize two-dimensional gel protein database: towards an integrated genome analysis program

This paper describes the first maize database of proteins separated by two-dimensional electrophoresis. Fifty-six coleoptile proteins and 18 leaf proteins from two maize lines were partially microsequenced. Thirty-six proteins (49%) displayed high similarity with database proteins. Nine of these proteins, representing five different functions, had never been described in maize. No conclusive function could be found for 45 polypeptides (61% of the microsequenced proteins). In addition, an alternative identification method, based on amino acid analysis, allowed candidates to be proposed for 17 proteins out of 44 additional proteins analyzed in the coleoptiles. These results are stored in a database which also includes, when available, genetic information about the chromosomal location of structural genes and regulatory factors of proteins. This database is being used in the context of a project on the genetic mapping of the expressed genome in maize.