AUTHOR=Xu Zhe , Tong Qi , Lv Wuyun , Xiao Yu , Wang Zhengyi 

TITLE=Phosphocholine cytidylyltransferase MoPct1 is crucial for vegetative growth, conidiation, and appressorium-mediated plant infection by Magnaporthe oryzae

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1136168

DOI=10.3389/fmicb.2023.1136168

ISSN=1664-302X

ABSTRACT=<p>Phosphatidylcholine (PC) plays crucial biological roles in eukaryotic cells. In <italic>Saccharomyces cerevisiae</italic>, apart from phosphatidylethanolamine (PE) methylation pathway, PC is also synthesized via CDP–choline pathway. Phosphocholine cytidylyltransferase Pct1 is the rate-limiting enzyme to catalyze the conversion from phosphocholine to CDP–choline in this pathway. Here, we report the identification and functional characterization of an ortholog of the budding yeast <italic>PCT1</italic> in <italic>Magnaporthe oryzae</italic>, named <italic>MoPCT1</italic>. Targeted gene deletion mutants of <italic>MoPCT1</italic> were impaired in vegetative growth, conidiation, appressorium turgor accumulation and cell wall integrity. Also, the mutants were severely compromised in appressorium-mediated penetration, infectious growth and pathogenicity. Western blot analysis revealed that cell autophagy was activated by the deletion of <italic>MoPCT1</italic> under nutrient-rich conditions. Moreover, we found several key genes in PE methylation pathway, such as <italic>MoCHO2</italic>, <italic>MoOPI3</italic>, and <italic>MoPSD2</italic>, were significantly up-regulated in the <italic>ΔMopct1</italic> mutants, indicating that a pronounced compensation effect exists between the two PC biosynthesis pathways in <italic>M. oryzae</italic>. Interestingly, in the <italic>ΔMopct1</italic> mutants, histone H3 was hypermethylated and expression levels of several methionine cycling-related genes were significantly up-regulated, suggesting that <italic>MoPCT1</italic> is involved in histone H3 methylation and methionine metabolism. Taken together, we conclude that the phosphocholine cytidylyltransferase coding gene <italic>MoPCT1</italic> plays important roles in vegetative growth, conidiation and appressorium-mediated plant infection by <italic>M. oryzae</italic>.</p>