Aspergillus nidulans sod^VIC1mutation causes defects in cell wall biogenesis and protein secretion

Abstract

Growth at the restrictive temperature (42 degrees C) of Aspergillus nidulans B120, carrying the conditional-lethal mutation sod(VI)C1, was partially improved by the addition of 1.0 M sorbitol to the medium. The mutant grown at 42 degrees C, with osmotic stabilizer, showed abnormal hyphal morphology, a decrease in beta-1,3-glucan synthase activity as well as cell wall sugar content, but an increase in chitin synthase activity and N-acetyl-glucosamine content. The mutation also affected the secretion of extracellular protease. The temperature-dependent osmo-sensitive phenotype of a Saccharomyces cerevisiae alpha-COP mutation can be rescued by the A. nidulans sod(VI)C(+) gene. These results indicate that the sod(VI)C1 mutation affects proper processing of secretory proteins destined for the surface of cells or beyond.

Depletion of ε-COP in the COPI Vesicular Coat Reduces Cleistothecium Production inAspergillus nidulans

“…Our previous study showed that the C-terminal domains of both α-COP and ε-COP are essential for their interaction, and that the N-terminal WD40 motif of α-COP and the TPR region of ε-COP are involved in controlling the interaction between these two COPs in A. nidulans [ 16 ]. We also reported that A. nidulans α-COP can substitute for S. cerevisiae α-COP functions in vivo [ 15 ]. In yeast, ε-COP is known to stabilize the thermo-sensitive α-COP mutation.…”

“…In Aspergillus nidulans , α-COP is essential for viability. However, like in yeast, a mutation in A. nidulans α-COP gene results in a temperature-sensitive defect in growth, cell-wall construction, and protein secretion [ 14 , 15 ]. Interestingly, the temperature dependent-osmo-sensitive phenotype of the S. cerevisiae α-COP mutant is suppressed by introduction of the A. nidulans sod VI C (stabilization of disomy) gene for α-COP [ 15 ].…”

“…However, like in yeast, a mutation in A. nidulans α-COP gene results in a temperature-sensitive defect in growth, cell-wall construction, and protein secretion [ 14 , 15 ]. Interestingly, the temperature dependent-osmo-sensitive phenotype of the S. cerevisiae α-COP mutant is suppressed by introduction of the A. nidulans sod VI C (stabilization of disomy) gene for α-COP [ 15 ]. In addition, the C-terminus of the A. nidulans ε-COP, AneA, including tetratrico peptide repeat (TPR: W 4 G 8 Y 11 G 15 Y 17 A 20 Y 24 A 27 P 32 ) interacts with the C-terminus of α-COP [ 16 ].…”

Sbg1 Is a Novel Regulator for the Localization of the β-Glucan Synthase Bgs1 in Fission Yeast

“…In A . nidulans , the α-COP protein Sod VI Cp plays a role in cell wall synthesis and protein secretion by affecting β-glucan synthase activity [32]. Moreover, S .…”

Role of LAMMER Kinase in Cell Wall Biogenesis during Vegetative Growth ofAspergillus nidulans

“…Chemical analysis of the composition of the cell wall was performed using the method described previously [ 14 ]. Sensitivity toward cell wall-perturbing agents was investigated via the method described by Kovács et al [ 5 ] using media supplemented with Calcofluor white (CFW) or Congo red (CR).…”