The Rrop GTPase switch turns on polar growth in pollen.
Pollen-tube growth not only represents an essential stage of plant reproduction but also provides an attractive model for studying cell polarity and morphogenesis. For many years, pollen-tube growth has been known to require a tip-focused Ca2+ gradient and dynamic F actin, but the way that these are controlled remained a mystery until recently. Rop appears to be activated at growth sites by a tip-localized growth cue, acting as a central switch that controls the polar growth of pollen tubes, probably having its effect through phosphoinositides and Ca2+. These findings have begun to shed light on the molecular basis of pollen-tube growth and cell morphogenesis in plants.
Zheng
Z L
ZL
Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA.
Yang
Z
Z
D000199:Actins / Q000378:metabolism; D020013:Calcium Signaling; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D011058:Pollen / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism
D000199:Actins; D017853:Phosphotransferases (Alcohol Group Acceptor); C020077:1-phosphatidylinositol-4-phosphate 5-kinase; D020558:GTP Phosphohydrolases