The role of sugar supply and signalling in the regulation of maize leaf growth.

Plants need light to grow and how plants regulate growth in response to light is the central theme in this project. Light drives the generation of sugars by photosynthesis and sugars act as signalling molecules that regulate developmental processes including cell division and expansion. Studies on growth regulation by sugars have been done largely in Arabidopsis, but we use the maize leaf due it its larger size that allows to performe analyses of the sugar metabolism, particularly in proliferating and expanding cells that drive growth. Our preliminary data show that shading mature leaves inhibits growth of younger leaves, but shading the mature part of the growing leaf stimulates growth. Also 4 mutations of sugar metabolism genes affect leaf growth. To understand how this regulation works we study to what extent sugar is transported from source leaves and from the mature part of growing leaf (by studying transport of radioactive 11CO2 fed to different leaves. How this sugar regulates leaf growth at cellular (cell division and expansion), metabolic (different sugars and hormones); biochemical (enzyme activities) and transcriptional (mRNA )levels in the growth zone at the base of the leaf. Our combined results will lead to new knowledge about the mechanism linking genetic, molecular, cellular and physiological levels to whole organ growth rates, which can be used to improve the growth of crop species in the context of changing climate conditions.

Keywords:EXPERIMENTAL STUDY

Disciplines:Plant biology

Project type:Collaboration project