MoCDC14 is important for septation during conidiation and appressorium formation in Magnaporthe oryzae

論文信息：Haohui Li, Shulin Cao, Chengkang Zhang , Yonghui Zhang, Qiang Zhang, Jinrong Xu, Chenfang Wang. MoCDC14 is important for septation during conidiation and appressorium formation in Magnaporthe oryzae. Molecular Plant Pathology (2018) 19(2), 328–340.

JCR分區(qū)Q1, IF=4.297

論文摘要：As a typical foliar pathogen, appressorium formation and pene- tration are critical steps in the infection cycle of Magnaporthe oryzae. Because appressorium formation and penetration are closely co-regulated with the cell cycle, and Cdc14 phosphatases have an antagonistic relationship with cyclin-dependent kinases (CDKs) on proteins related to mitotic exit and cytokinesis, in this study, we functionally characterized the MoCDC14 gene in M. oryzae. The Mocdc14 deletion mutant showed significantly reduced growth rate and conidiation. It was also defective in sep- tum formation and nuclear distribution. Septation was irregular in Mocdc14 hyphae and hyphal compartments became multi- nucleate. Mutant conidia often showed incomplete septa or lacked any septum. During appressorium formation, the septum delimiting appressoria from the rest of the germ tubes was often formed far away from the neck of the appressoria or not formed at all. Unlike the wild-type, some mutant appressoria had more than one nucleus at 24 h. In addition to appressoria, melaniza- tion occurred on parts of the germ tubes and conidia, depending on the irregular position of the appressorium-delimiting septum. The Mocdc14 mutant was also defective in glycogen degradation during appressorium formation and appressorial penetration of intact plant cells. Similar defects in septum formation, melaniza- tion and penetration were observed with appressorium-like struc- tures formed at hyphal tips in the Mocdc14 mutant. Often a long fragment of mutant hyphae was melanized, together with the apical appressorium-like structures. These results indicate that MoCDC14 plays a critical role in septation, nuclear distribution and pathogenesis in M. oryzae, and correct septum formation during conidiogenesis and appressorium formation requires the MoCdc14 phosphatase.