Affiliation:
1. Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
2. State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
Abstract
The surface of the Saccharomyces cerevisiae spore wall exhibits a ridged appearance. The outermost layer of the spore wall is believed to be a dityrosine layer, which is primarily composed of a crosslinked dipeptide bisformyl dityrosine. The dityrosine layer is impervious to protease digestion; indeed, most of bisformyl dityrosine molecules remain in the spore after protease treatment. However, we find that the ridged structure is removed by protease treatment. Thus, a ridged structure is distinct from the dityrosine layer. By proteomic analysis of the spore wall-bound proteins, we found that hydrophilin proteins, including Sip18, its paralog Gre1, and Hsp12, are present in the spore wall. Mutant spores with defective hydrophilin genes exhibit functional and morphological defects in their spore wall, indicating that hydrophilin proteins are required for the proper organization of the ridged and proteinaceous structure. Previously, we found that RNA fragments were attached to the spore wall in a manner dependent on spore wall-bound proteins. Thus, the ridged structure also accommodates RNA fragments. Spore wall-bound RNA molecules function to protect spores from environmental stresses.
Funder
National first-class discipline program of Light Industry Technology and Engineering
Project 111
Collaborative Innovation Center of Jiangsu Modern Industrial Fermentation
International Joint Research Laboratory for the production of therapeutic glycoproteins at Jiangnan University
Fundamental Research Funds for the Central Universities
NSFC
Subject
Plant Science,Ecology, Evolution, Behavior and Systematics,Microbiology (medical)
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