The Branching Gene RAMOSUS1 Mediates Interactions among Two Novel Signals and Auxin in Pea

Genetic, and physiological evidence that RMS1 plays a central role in a shoot-to-root-to-shoot feedback system that regulates shoot branching in pea

Eloise Foo; Erika Bullier; Magali Goussot; Fabrice Foucher; Catherine Rameau; Christine Anne Beveridge

2005

Scholarcy highlights

  • The timing of axillary bud outgrowth and the ensuing growth of axillary shoots is one of the key determinants of shoot architecture
  • In pea plants with two decapitated shoots, replacement of one shoot tip with exogenous indole3-acetic acid can lead to inhibition of branching in both shoots even though very little auxin moves between shoots
  • We present evidence that RMS1 expression is stimulated by a mobile feedback signal that is largely independent from IAA and appears to require RMS2
  • The expression studies presented here indicate that RMS1, which regulates levels of a novel hormone-like branching inhibitor, plays a central role in the signal cross talk that regulates shoot branching
  • We propose that IAA interacts with RMS1, at least partly, by stimulating expression of the RMS1 gene
  • We provide molecular evidence for an additional IAA-independent feedback signal that stimulates expression of the RMS1 gene
  • Because decapitation and triiodobenzoic acid may affect the levels and/or transport of other long-distance signals, the small increase in RMS1 expression in intact plants in response to indole3-acetic acid was an important observation

Need more features? Save interactive summary cards to your Scholarcy Library.