In:
Frontiers in Plant Science, Frontiers Media SA, Vol. 13 ( 2022-9-9)
Abstract:
The rice blast fungus Magnaporthe oryzae spores differentiate and mature into functional appressoria by sensing the host surface signals. Environmental stimuli are transduced into cells through internalization during appressorium formation, such as in the cAMP-PKA pathway. Here, we describe a novel contribution to how appressoria mature on the surface of a leaf, and its connection to endosomes and the cAMP-PKA pathway. An appressorium membrane-specific protein, Pams1, is required for maintaining endosomal structure, appressorium maturation, and virulence in M. oryzae . During appressorium development, Pams1 was translocated from the cell membrane to the endosomal membrane. Deletion of PAMS1 led to the formation of two types of abnormal appressoria after 8 h post inoculation (hpi): melanized type I had a reduced virulence, while pale type II was dead. Before 8 hpi, Δ pams1 formed appressoria that were similar to those of the wild type. After 8 hpi, the appressoria of Δ pams1 was differentiated into two types: (1) the cell walls of type I appressoria were melanized, endosomes were larger, and had a different distribution from the wild type and (2) Type II appressoria gradually stopped melanization and began to die. The organelles, including the nucleus, endosomes, mitochondria, and endoplasmic reticula, were degraded, leaving only autophagic body-like vesicles in type II appressoria. The addition of exogenous cAMP to Δ pams1 led to the formation of a greater proportion of type I appressoria and a smaller proportion of type II appressoria. Thus, defects in endosomal structure and the cAMP-PKA pathway are among the causes of the defective appressorium maturation and virulence of Δ pams1 .
Type of Medium:
Online Resource
ISSN:
1664-462X
DOI:
10.3389/fpls.2022.955254
DOI:
10.3389/fpls.2022.955254.s001
DOI:
10.3389/fpls.2022.955254.s002
DOI:
10.3389/fpls.2022.955254.s003
DOI:
10.3389/fpls.2022.955254.s004
Language:
Unknown
Publisher:
Frontiers Media SA
Publication Date:
2022
detail.hit.zdb_id:
2687947-5
detail.hit.zdb_id:
2613694-6
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