Isolation, expression, and functional analysis of anther-specific genes

In this study, isolation, expression, and sequence analysis have been achieved for six novel anther-specific transcripts of Arabidopsis thaliana. Additional achievements have been functional characterization of one of these genes, and identification of T-DNA insertions associated with gametophyte developmental and functional defects.;The ATA7 gene is expressed specifically in the anther tapetum cells during pollen development, and the cDNA sequence suggests that it encodes a protein related to the lipid transfer proteins, but differs from them in charge. Whereas the known lipid transfer proteins are basic, ATA7 encodes a protein with predicted neutral isoelectric point and lacks three highly conserved basic residues of the known lipid transfer proteins. It seems reasonable to suspect that this change reflects a difference in binding specificity. This finding combined with ultrastructural and cytochemical evidence for tryphine synthesis in the tapetum cells is consistent with a role for neutral lipid binding proteins in the deposition of tryphine on pollen grains.;The ATA20 gene is also tapetum-specific in expression, and the cDNA sequence suggests repeating amino acid motifs that are likely to have structural roles. Unlike previously described tapetum-specific transcripts encoding glycine rich proteins, the predicted ATA20 sequence does not share the oleosin domain and is more similar to glycine-rich proteins of the cell wall.;Another tapetum-specific gene (ATA27) is predicted to encode a protein with high similarity (...