title: FgKin1 kinase localizes to the septal pore and plays a role in hyphal growth, ascospore germination, pathogenesis, and localization of Tub1 beta-tubulins in Fusarium graminearum.
abstract: The Kin1/Par-1/MARK kinases regulate various cellular processes in eukaryotic organisms. Kin1 orthologs are well conserved in fungal pathogens but none of them have been functionally characterized. Here, we show that KIN1 is important for pathogenesis and growth in two phytopathogenic fungi and that FgKin1 regulates ascospore germination and the localization of Tub1 β-tubulins in Fusarium graminearum. The Fgkin1 mutant and putative FgKIN1(S172A) kinase dead (nonactivatable) transformants were characterized for defects in plant infection, sexual and asexual reproduction, and stress responses. The localization of FgKin1 and two β-tubulins were examined in the wild-type and mutant backgrounds. Deletion of FgKIN1 resulted in reduced virulence and defects in ascospore germination and release. FgKin1 localized to the center of septal pores. FgKIN1 deletion had no effect on Tub2 microtubules but disrupted Tub1 localization. In the mutant, Tub1 appeared to be enriched in the nucleolus. In Magnaporthe oryzae, MoKin1 has similar functions in growth and infection and it also localizes to septal pores. The S172A mutation had no effect on the localization and function of FgKIN1 during sexual reproduction. These results indicate that FgKIN1 has kinase-dependent and independent functions and it specifically regulates Tub1 β-tubulins. FgKin1 plays a critical role in ascospore discharge, germination, and plant infection.
authors: State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China.
authors: Yongping
authors: Y
authors: Luo
authors: Hongchang
authors: H
authors: Zhang
authors: Linlu
authors: L
authors: Qi
authors: Shijie
authors: S
authors: Zhang
authors: Xiaoying
authors: X
authors: Zhou
authors: Yimei
authors: Y
authors: Zhang
authors: Jin-Rong
authors: JR
authors: Xu
mesh_terms: D002473:Cell Wall / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005670:Fusarium / Q000378:metabolism / Q000472:pathogenicity* / Q000502:physiology; D017353:Gene Deletion; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D025301:Hyphae / Q000254:growth & development / Q000378:metabolism; D020082:Magnaporthe / Q000378:metabolism / Q000472:pathogenicity; D009154:Mutation; D030781:Organisms, Genetically Modified; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D013172:Spores, Fungal / Q000254:growth & development* / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism*; D014774:Virulence / Q000235:genetics; D003313:Zea mays / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D014404:Tubulin; D049452:Green Fluorescent Proteins; D017346:Protein Serine-Threonine Kinases
keywords: ascospore germination; ascospore release; beta-tubulins; cytokinesis; pathogenesis; septation