Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
EMBO J. 2000 Aug 15;19(16):4248-56.

ACAULIS5, an Arabidopsis gene required for stem elongation, encodes a spermine synthase.

Author information

  • 1Division of Biological Sciences, Graduate School of Science, Hokkaido University, N10, W8, Sapporo 060-0810, Japan.

Abstract

Polyamines have been implicated in a wide range of biological processes, including growth and development in bacteria and animals, but their function in higher plants is unclear. Here we show that the Arabidopsis: ACAULIS5 (ACL5) gene, whose inactivation causes a defect in the elongation of stem internodes by reducing cell expansion, encodes a protein that shares sequence similarity with the polyamine biosynthetic enzymes spermidine synthase and spermine synthase. Expression of the recombinant ACL5 protein in Escherichia coli showed that ACL5 possesses spermine synthase activity. Restoration of the acl5 mutant phenotype by somatic reversion of a transposon-induced allele suggests a non-cell-autonomous function for the ACL5 gene product. We also found that expression of the ACL5 cDNA under the control of a heat shock gene promoter in acl5 mutant plants restores the phenotype in a heat shock-dependent manner. The results of the experiments showed that polyamines play an essential role in promotion of internode elongation through cell expansion in Arabidopsis: We discuss the relationships to plant growth regulators such as auxin and gibberellins that have related functions.

PMID:
10944107
[PubMed - indexed for MEDLINE]
PMCID:
PMC302034
Free PMC Article

Images from this publication.See all images (7)Free text

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk