Wei-Cai Yang
Institute of Genetics and Developmental Biology, China
Title: Pollen Tube Guidance: The Interplay between Male and Female Gametophytes
Biography
Biography: Wei-Cai Yang
Abstract
During evolution, novel reproductive structures and mechanisms have been emerged in plants. In angiosperms, such evolutionary development is manifested by the flower, multicellular gametophyte, double fertilization, loss of sperm motility, and siphonogamy in which the immotile sperm was delivered to the egg by a pollen tube produced by the male gametophyte (pollen), a process named pollen tube guidance (PTG). Previous studies suggested that PTG requires the intimate interactions between the pollen tube and maternal tissue of the pistil and the female gametophyte respectively. Through genetic screen, we isolated a number of Arabidopsis mutants that disrupt these processes. CCG, a central cell-specifically expressed gene, is required for the female gametophyte to attract the pollen tube. CCG encodes a nuclear protein that regulates the expression of a number genes important for PTG via interacting with RNA polymerase II, the Mediator complex and AGL transcription factors. POD1, a pollen tube-expressed gene, is required for the male gametophyte to respond to the female signals. POD1 encodes a ER protein that interact specifically with CRT3, suggesting that it might play a role in the protein folding of putative receptor proteins. Recently, we identified the male MDIS/MDIK receptor complex that recognizes the female attracting signals. These findings provide novel insight to mechanims controlling PTG. And more recent progresses will be discussed.