Comparative genomics of Arabidopsis and maize: prospects and limitations

Abstract

The completed Arabidopsis genome seems to be of limited value as a model for maize genomics. In addition to the expansion of repetitive sequences in maize and the lack of genomic micro-colinearity, maize-specific or highly-diverged proteins contribute to a predicted maize proteome of about 50,000 proteins, twice the size of that of Arabidopsis.

Figure 1

Maize inflorescences. The separation of (a) female inflorescence (ear) and (b) male inflorescence (tassel) is one of the key features of the maize plant responsible for its pivotal role in plant genetics, greatly simplifying controlled pollination (photos courtesy of Tom Peterson, Iowa State University).

Figure 2

Comparison of maize proteins predicted from EST sequences with Arabidopsis proteins. A non-redundant set of protein sequences consisting of at least 120 amino acids each, derived from 27,294 distinct maize ESTs, was compared with 25,617 putative Arabidopsis proteins at different BLASTP stringency levels. The percentages in each pie chart give the fractions of the two sequence sets involved in these matches, at each stringency level.