Neutral Lipids in the Flowers of Arabidopsis Mutants

University Of California-Riverside, Riverside CA

Investigators

Abstract

Sexual reproduction in plants is a dynamic process, and its mechanism and control are complicated. Research into the molecular basis of flowering and fruiting is intellectually intriguing as well as practical in agriculture. Promoting sexual reproduction could enhance the yield of fruits and seeds. Suppressing the process could increase the yield of vegetable produce. Other possible manipulations include utilizing male sterile genes to produce hybrid seeds, generating seedless fruits, and promoting self fertilization. A major step in sexual reproduction is the interaction between the male sperm-containing pollen and the female egg-containing part in the flowers. This interaction is initiated largely by the molecules on the pollen surface. The pollen coat contains water-insoluble lipids and semi-water-soluble proteins as the major constituents. These lipids and proteins originate from subcellular particles in the parental cells enclosing the maturing pollen. The laboratory of Professor Anthony Huang at the University of California at Riverside will study these subcellular particles in Arabidopsis, a model plant of the cabbage family. The studies will emphasize the lipid and protein constituents in terms of their selective degradation and retention, their transport to and deposition on the pollen surface, and their function in the pollination and fertilization process. Arabidopsis mutants deficient in the lipids and proteins will be employed to dissect this parent-to-pollen pathway. The results will delineate the mechanism of the control that the parental cells have over pollen maturation, especially on the pollen coat formation. They will also define the functions of the abundant lipids and proteins in the pollen coat in pollination, pollen germination, and tube penetration into the stigma.