title: N-Glycosylation of Gel1 or Gel2 is vital for cell wall β-glucan synthesis in Aspergillus fumigatus.
abstract: Fungal cell wall is a dynamic structure that communicates with and protects the cell from outside stress. In Aspergillus fumigatus, the cell wall β-glucans are mainly elongated by β-1,3-glucanosyltransferases Gels, which consist of seven family members (Gel1-7) utilizing β-1,3-glucan chains as substrates. Previously, we have shown that the mutant deficient of N-glycan processing displays a reduction in the cell wall β-glucans, suggesting that N-glycosylation is required for the proper function of β-1,3-glucanosyltransferase. To verify this hypothesis, in this study, the gene encoding β-1,3-glucanosyltransferase Gel1 or Gel2 was deleted in the Δcwh41 mutant to construct a double-mutant Δgel1Δcwh41 or Δgel2Δcwh41. The growth phenotypes of both double mutants were similar to the single-mutant Δcwh41, suggesting that Gel1 and Gel2 are proteins that are mainly affected by deficient N-glycan processing in Δcwh41. Furthermore, the mutant Δgel1(Gel1-NM) or Δgel2(Gel2-NM), in which all potential N-glycosylation sites on Gel1 or Gel2 were removed by site-directed mutagenesis, showed phenotypes similar to the single-mutant Δgel1 or Δgel2. Biochemical analysis revealed that N-glycosylation was essential for the function of Gel1 or Gel2 and thus required for β-glucan synthesis in A. fumigatus.
authors: State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
authors: Wan
authors: W
authors: Zhao
authors: Yang
authors: Y
authors: Lü
authors: Haomiao
authors: H
authors: Ouyang
authors: Hui
authors: H
authors: Zhou
authors: Jianghong
authors: J
authors: Yan
authors: Ting
authors: T
authors: Du
authors: Cheng
authors: C
authors: Jin
mesh_terms: D001232:Aspergillus fumigatus / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism*; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000235:genetics / Q000378:metabolism*; D005936:Glucans / Q000096:biosynthesis*; D006031:Glycosylation; D009154:Mutation
chemical_list: D005936:Glucans; C117939:1,3-beta-glucanosyltransferase; D004693:Glucan Endo-1,3-beta-D-Glucosidase
keywords: Aspergillus fumigatus; N-glycosylation; cell wall; cell wall integrity; β-1,3-glucanosyltranferase