title: PnPMA1, an atypical plasma membrane H(+)-ATPase, is required for zoospore development in Phytophthora parasitica.
abstract: Biflagellate zoospores are the major infective agents that initiate plant infection for most Phytophthora species. Once released from sporangia, zoospores swim and use a number of tactic responses to actively target host tissues. However, the molecular mechanisms controlling zoospore development and behaviour are largely unknown. Previous studies have shown that the PnPMA1 gene is highly expressed in zoospores and germinated cysts of Phytophthora parasitica and encodes an atypical plasma membrane H(+)-ATPase containing an insertion of ~155 amino acid residues at the C terminus. Using topology determination we now show that the C-terminal insertion loop in the PnPMA1 protein is located in the extracellular space. To elucidate the biological function of PnPMA1, PnPMA1-deficient transformants were generated by homology-dependent gene silencing and were confirmed by quantitative PCR of PnPMA1 transcripts and detection of associated small interfering RNAs (siRNAs). High levels of PnPMA1 silencing in P. parasitica resulted in production of nonflagellate and large aberrant zoospores, rapid transition from zoospores to cysts, and a decreased germination rate of cysts. These results indicate that PnPMA1 plays important roles in zoospore development.
authors.affiliation: State Key Laboratory of Crop Stress Biology in Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
authors.forename: Meixiang
authors.initials: M
authors.lastname: Zhang
authors.forename: Yuling
authors.initials: Y
authors.lastname: Meng
authors.forename: Qinhu
authors.initials: Q
authors.lastname: Wang
authors.forename: Dandan
authors.initials: D
authors.lastname: Liu
authors.forename: Junli
authors.initials: J
authors.lastname: Quan
authors.forename: Adrienne R
authors.initials: AR
authors.lastname: Hardham
authors.forename: Weixing
authors.initials: W
authors.lastname: Shan
mesh_terms: D002462:Cell Membrane / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D010838:Phytophthora / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D010935:Plant Diseases / Q000469:parasitology; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013170:Spores / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*
chemical_list: D006180:Proton-Translocating ATPases