Sequence of Asr2, a member of a gene family from Lycopersicon esculentum encoding chromosomal proteins: homology to an intron of the polygalacturonase gene

Abstract

Asr is a family of genes regulated by abscisic acid, stress and ripening in tomato. Asr2, a recently reported member of this family, has been further characterized through sequencing of a genomic clone. We report the sequencing of 2029 bp of Asr2, spanning its AT-rich (62%) upstream region with probable regulatory functions. This region displays several candidate TATA and CAAT boxes that might be involved in transcription initiation, as well as a motif similar to one previously reported to be responsible for induction by ABA. Apart from that, we found a 108-bp stretch from the 3’ non-coding region which displays a high homology (92%) to a region within intron 6 of the polygalacturonase gene, which, like Asr2, is expressed in ripening tomato fruit. This striking similarity suggests the presence of either a conserved regulatory motif or an abundant mobile element.

Key Words:

• tomato
• abscisic acid
• promoter
• polygalacturonase gene