RIB1 — Aspergillus fumigatus

Summary

AFU1G13300 (symbol RIB1, preferred name AfRIB1) on Aspergillus fumigatus chromosome 1 encodes a GTP cyclohydrolase II (EC 3.5.4.25) with cyclohydrolase activity, GTP binding, and metal binding, belonging to the RibA family and GTP_cyclohydro_II domain. The gene is associated with riboflavin and vitamin A biosynthesis, homeostasis, and localizes to the cytosol and nucleus. Phenotypic associations include abnormal cell cycle progression (arrest at G1, G2/M, and premature metaphase/telophase), increased autophagy, abnormal budding patterns, decreased viability and sporulation, increased chitin deposition, altered redox state, and abnormal cell size and shape. Studies of related genes in other fungi link the family to decreased alkaline pH resistance, anaerobic growth, desiccation resistance, and chronological lifespan, as well as increased innate thermotolerance.