Molecular Plant
Volume 6, Issue 1, January 2013, Pages 164-173
Journal home page for Molecular Plant

Research Article
Long-Distance Signaling in bypass1 Mutants: Bioassay Development Reveals the bps Signal to Be a Metabolite

https://doi.org/10.1093/mp/sss129Get rights and content
Under an Elsevier user license
open archive

ABSTRACT

Root-to-shoot signaling is used by plants to coordinate shoot development with the conditions experienced by the roots. A mobile and biologically active compound, the bps signal, is over-produced in roots of an Arabidopsis thaliana mutant called bypass1 (bps1), and might also be a normally produced signaling molecule in wild-type plants. Our goal is to identify the bps signal chemically, which will then allow us to assess its production in normal plants. To identify any signaling molecule, a bioassay is required, and here we describe the development of a robust, simple, and quantitative bioassay for the bps signal. The developed bioassay follows the growth-reducing activity of the bps signal using the pCYCB1;1::GUS cell cycle marker. Wild-type plants carrying this marker, and provided the bps signal through either grafts or metabolite extracts, showed reduced cell division. By contrast, control grafts and treatment with control extracts showed no change in pCYCB1;1::GUS expression. To determine the chemical nature of the bps signal, extracts were treated with RNase A, Proteinase K, or heat. None of these treatments diminished the activity of bps1 extracts, suggesting that the active molecule might be a metabolite. This bioassay will be useful for future biochemical fractionation and analysis directed toward bps signal identification.

Summary

A bioassay for the mobile and biologically active compound over-produced in bypass roots was developed. Chemical characterization suggests that the compound is a small mobile metabolite.

Key words

hormone biology
metabolic regulation
physiology of plant growth
secondary metabolism/natural products
signaling
organismal level
development

Cited by (0)

Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.