Dual function of Arabidopsis glucan synthase-like genes GSL8 and GSL10 in male gametophyte development and plant growth

• Published in: The Plant journal : for cell and molecular biology Vol. 54; no. 5; pp. 911 - 923
• Main Authors: Töller, Armin, Brownfield, Lynette, Neu, Christina, Twell, David, Schulze-Lefert, Paul
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01-06-2008; Blackwell Publishing Ltd; Blackwell Science
• Subjects: 1,3-beta-glucan synthase; Arabidopsis - enzymology; Arabidopsis - growth & development; Base Sequence; Biological and medical sciences; Botany; callose synthase; cell-wall integrity; Cellular biology; DNA Primers; DNA, Plant; Fundamental and applied biological sciences. Psychology; gametophytic lethality; Genes, Plant; Glucosyltransferases - genetics; Isoenzymes - genetics; Males; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Mutation; plant growth; Plant growth. Development of the storage organs; Plant physiology and development; Pollen - ultrastructure; pollen development; pollen mitosis; Reverse Transcriptase Polymerase Chain Reaction; Transgenic plants; Vegetative apparatus, growth and morphogenesis. Senescence; gametophytic lethality; Growth; Mitosis; Synthase; Cell wall; Gene; Cruciferae; Dicotyledones; Angiospermae; Development; Pollen; plant growth; callose synthase; Enzyme; Arabidopsis; Perturbation; Growth habit; Callose; cell-wall integrity; pollen development; Microspore; pollen mitosis; Spermatophyta; Mutation; Cytoplasm
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1111/j.1365-313x.2008.03462.x

Members of the glucan synthase-like (GSL) family are believed to be involved in synthesis of the cell-wall component callose in specialized locations throughout the plant. We identified two members of the Arabidopsis GSL gene family, GSL8 and GSL10, that are independently required for male gametophyte development and plant growth. Analysis of gsl8 and gsl10 mutant pollen during development revealed specific malfunctions associated with asymmetric microspore division. GSL8 and GSL10 are not essential for normal microspore growth and polarity, but play a role in entry of microspores into mitosis. Impaired function of GSL10 also leads to perturbation of microspore division symmetry, irregular callose deposition and failure of generative-cell engulfment by the cytoplasm of the vegetative cell. Silencing of GSL8 or GSL10 in transgenic lines expressing gene-specific dsRNAi constructs resulted in a dwarfed growth habit, thereby revealing additional and independent wild-type gene functions for normal plant growth.