A Myb transcription factor of Phytophthora sojae, regulated by MAP kinase PsSAK1, is required for zoospore development.

Abstract

PsSAK1, a mitogen-activated protein (MAP) kinase from Phytophthora sojae, plays an important role in host infection and zoospore viability. However, the downstream mechanism of PsSAK1 remains unclear. In this study, the 3'-tag digital gene expression (DGE) profiling method was applied to sequence the global transcriptional sequence of PsSAK1-silenced mutants during the cysts stage and 1.5 h after inoculation onto susceptible soybean leaf tissues. Compared with the gene expression levels of the recipient P. sojae strain, several candidates of Myb family were differentially expressed (up or down) in response to the loss of PsSAK1, including of a R2R3-type Myb transcription factor, PsMYB1. qRT-PCR indicated that the transcriptional level of PsMYB1 decreased due to PsSAK1 silencing. The transcriptional level of PsMYB1 increased during sporulating hyphae, in germinated cysts, and early infection. Silencing of PsMYB1 results in three phenotypes: a) no cleavage of the cytoplasm into uninucleate zoospores or release of normal zoospores, b) direct germination of sporangia, and c) afunction in zoospore-mediated plant infection. Our data indicate that the PsMYB1 transcription factor functions downstream of MAP kinase PsSAK1 and is required for zoospore development of P. sojae.

• Authors: Meng Zhang, Jing Lu, Kai Tao, Wenwu Ye, Aining Li, Xiaoyun Liu, Liang Kong, Suomeng Dong, Xiaobo Zheng, Yuanchao Wang
• Journal: PloS one (PLoS One) Vol. 7 Issue 6 Pg. e40246 ( 2012) ISSN: 1932-6203 [Electronic] United States
• PMID: 22768262 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Transcription Factors
• Mitogen-Activated Protein Kinases

Topics

• Amino Acid Sequence
• Cell Nucleus (metabolism)
• Gene Expression Profiling
• Gene Expression Regulation
• Gene Silencing
• Mitogen-Activated Protein Kinases (chemistry, metabolism)
• Molecular Sequence Data
• Phytophthora (cytology, enzymology, genetics, growth & development)
• Plant Diseases (microbiology)
• Reproduction, Asexual (genetics)
• Reverse Transcriptase Polymerase Chain Reaction
• Glycine max (microbiology)
• Sporangia (cytology, genetics, growth & development)
• Transcription Factors (genetics, metabolism)