Haploid and diploid expression of a Brassica campestris anther-specific gene promoter in Arabidopsis and tobacco

Abstract

The anther-specific cDNA clone Bcp1 from Brassica campestris is expressed in both the haploid pollen and diploid tapetum, as shown by in situ hybridization. We have isolated Bgpl, a genomic clone homologous to Bcpl. The coding region and extensive 5′ flanking sequences of Bgp1 have been sequenced, and the coding region shows 88% identity with Bcp1. RNA gel blot analysis confirmed the expression of Bgp1-specific transcripts in B. campestris pollen. A 767 by 5′ DNA fragment was fused to the reporter gene β-glucuronidase (gus) and introduced into both Arabidopsis thaliana and Nicotiana tabacum by transformation. This 5′ fragment directed high-level expression in the pollen and tapetum of transg..