Arf6 controls endocytosis and polarity during asexual development of Magnaporthe oryzae.
Asexual development of phytopathogenic fungi such as Magnaporthe oryzae involves morphological changes that require spatiotemporal regulation of polarized growth. ADP-ribosylation factor 6 (Arf6) is a small GTPase known to regulate membrane trafficking and organization of the actin cytoskeleton at the cell surface, and consequently has an impact on cell morphology and polarity. In this study, we have functionally characterized the Arf6 homolog in M. oryzae, showing that ▵arf6 exhibits hyperbranching at hyphal tips and morphologically abnormal conidia as a result of defective polarized growth. ▵arf6 hyphae are also defective in endocytosis as evidenced by a significant delay of FM4-64 uptake. Most ▵arf6 conidia display reduced conidial length, and have defects in conidial septum formation and nuclear distribution. Furthermore, ▵arf6 conidia show a disorganized actin cytoskeleton with random distribution of actin patches at the cell cortex and reduced accumulation of tropomyosin. Arf6-GFP is found to concentrate at the septum area and possibly in endocytic vesicles. Taken together, our data indicate that Arf6 plays an essential role in endocytosis and polarity establishment during asexual development of M. oryzae.
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.|Key Laboratory for Functional Genomics of Plant Fungal Pathogens, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Xiaohan
X
Zhu
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China zhoutengsheng@hotmail.com zhangdongmei127@126.com.|Key Laboratory for Functional Genomics of Plant Fungal Pathogens, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Tengsheng
T
Zhou
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.|Key Laboratory for Functional Genomics of Plant Fungal Pathogens, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Liqiong
L
Chen
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Shiqin
S
Zheng
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Shaohua
S
Chen
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China zhoutengsheng@hotmail.com zhangdongmei127@126.com.|Key Laboratory for Functional Genomics of Plant Fungal Pathogens, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Dongmei
D
Zhang
Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Guangpu
G
Li
Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.|Key Laboratory for Functional Genomics of Plant Fungal Pathogens, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Zonghua
Z
Wang
D000089982:ADP-Ribosylation Factor 6; D020727:ADP-Ribosylation Factors / Q000235:genetics* / Q000378:metabolism; D008841:Actin Cytoskeleton / Q000235:genetics* / Q000502:physiology; D016764:Cell Polarity / Q000235:genetics* / Q000502:physiology; D004705:Endocytosis / Q000235:genetics* / Q000502:physiology; D025301:Hyphae / Q000235:genetics / Q000254:growth & development; D020082:Magnaporthe / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity; D012275:Oryza / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology; D013172:Spores, Fungal / Q000235:genetics / Q000254:growth & development; D014335:Tropomyosin / Q000378:metabolism
D000089982:ADP-Ribosylation Factor 6; D014335:Tropomyosin; D020727:ADP-Ribosylation Factors
Rice blast; conidiogensis; membrane traffic; polarization