(1→3)-β-D-glucan synthases of plants.

Abstract

This thesis investigates the involvement of the plant glucan synthase-like or GSL genes in the formation of callose. Callose is a (1→3)-β-D-glucan widely distributed in higher plants. During normal plant growth, callose is found as a transitory component of the cell plate in dividing cells, it is a major component of pollen mother cell walls and pollen tubes, and is found as a structural component of plasmodesmatal canals, and is also in abscission zones and the phloem of dormant tissues. Callose is also deposited between the plasma membrane and the cell wall following exposure of plants to a range of abiotic and biotic stresses, including wounding, dessication, metal toxicity and microbial attack. Gene isolation was conducted in ryegrass, but functional analyses were conducted in barley. Ultimate proof of function of a single GSL gene was achieved in the plant model Arabidopsis.