Control of male germ‐cell development in flowering plants

Abstract

Plant reproduction is vital for species survival, and is also central to the production of food for human consumption. Seeds result from the successful fertilization of male and female gametes, but our understanding of the development, differentiation of gamete lineages and fertilization processes in higher plants is limited. Germ cells in animals diverge from somatic cells early in embryo development, whereas plants have distinct vegetative and reproductive phases in which gametes are formed from somatic cells after the plant has made the transition to flowering and the formation of the reproductive organs. Recently, novel insights into the molecular mechanisms underlying male germ-line initiation and male gamete development in plants have been obtained. Transcriptional repression of male germ-line genes in non-male germ-line cells have been identified as a key mechanism for spatial and temporal control of male germ-line development. This review focuses on molecular events controlling male germ-line development especially, on the nature and regulation of gene expression programs operating in male gametes of flowering plants.

Molecular repertoire of flowering plant male germ cells

“…Following asymmetric division, GRSF is absent from the smaller generative cell, leading to de-repression of gamete-specific genes. (Modified from Singh and Bhalla 2007) promising strategy for characterizing higher plant male gamete proteins that are critical for fertilization. The predicament of not knowing the surface proteins that mediate sperm-egg fusion in flowering plants is changing as newer, more sensitive approaches become available.…”

RA68 is required for postmeiotic pollen development in Oryza sativa

“…The place and time of PMII depends on the species. In the plant families of Cruciferae and Gramineae, PMII occurs during pollen maturity in the anther and mature pollen grains are tricellular, whereas in other plant families such as Solanaceae and Liliaceae, PMII occurs at the growing pollen tube after pollen pollination, so the mature pollen is bicellular at anthesis (Ma 2005;McCormick 1993McCormick , 2004Singh and Bhalla 2007;Twell et al 1998).…”

Stamen specification and anther development in rice

“…Pollen development requires cooperative functional interactions between gametophytic and sporophytic tissues within the anther, which includes a series of crucial events such as male sporogenous cell differentiation, meiosis, microspore formation and maturation. Recent reviews on stamen and anther development include articles by Scott et al [1] , Ma [2] , Singh et al [3] and Wilson and Zhang [4] . Meiosis in plants including Arabidopsis, rice (Oryza sativa) and maize (Zea mays) was also recently reviewed by Mercier [5] .…”