Isolation, expression and phylogenetic inheritance of an acetolactate synthase gene from Brassica napus

Document Type

Article

Publication Date

1989

Publication Title

Molecular and General Genetics MGG

Volume

219

Issue

3

First Page

413

Last Page

420

Abstract

SummaryAn acetolactate synthase gene was isolated and characterized from Brassica napus. This B. napus acetolactate synthase gene encodes a deduced polypeptide sequence of 637 amino acids which is 85% homologous to the corresponding proposed gene product from Arabidopsis thaliana. Peptide domains recently associated with herbicide resistance/sensitivity are conserved between the two sequences. From Southern analysis we conclude that the gene isolated is one member of a multigene acetolactate synthase gene family comprising four or five members. A probe spanning the presumptive transit peptide sequence of this gene was shown by Southern analysis to hybridize to a unique sequence in the B. napus genome. This unique probe was used to analyse DNA from B. campestris and B. oleracea, the presumed progenitors of B. napus. On the basis of restriction fragment length polymorphism, we conclude that the B. napus gene isolated here originated in B. campestris. Total acetolactate synthase-homologous transcripts were analysed in a variety of B. napus tissues, and showed preferential accumulation in rapidly growing material. The genomic clone was mutated in vitro at codon 173 to replace a proline residue with serine. This was re-introduced into plants, using Agrobacterium vectors, producing a herbicide-resistant phenotype which is characteristic of the predicted gene product.

DOI

10.1007/BF00259614

Share

COinS