| Title: | Chitin synthesis in Saccharomyces cerevisiae in response to supplementation of growth medium with glucosamine and cell wall stress |
| Author(s): | Bulik DA; Olczak M; Lucero HA; Osmond BC; Robbins PW; Specht CA; |
| Address: | "Department of Molecular and Cell Biology, School of Dental Medicine, Boston University, Boston, Massachusetts 02118, USA" |
| DOI: | 10.1128/EC.2.5.886-900.2003 |
| ISSN/ISBN: | 1535-9778 (Print) 1535-9786 (Electronic) 1535-9786 (Linking) |
| Abstract: | "In Saccharomyces cerevisiae most chitin is synthesized by Chs3p, which deposits chitin in the lateral cell wall and in the bud-neck region during cell division. We have recently found that addition of glucosamine (GlcN) to the growth medium leads to a three- to fourfold increase in cell wall chitin levels. We compared this result to the increases in cellular chitin levels associated with cell wall stress and with treatment of yeast with mating pheromone. Since all three phenomena lead to increases in precursors of chitin, we hypothesized that chitin synthesis is at least in part directly regulated by the size of this pool. This hypothesis was strengthened by our finding that addition of GlcN to the growth medium causes a rapid increase in chitin synthesis without any pronounced change in the expression of more than 6,000 genes monitored with Affymetrix gene expression chips. In other studies we found that the specific activity of Chs3p is higher in the total membrane fractions from cells grown in GlcN and from mutants with weakened cell walls. Sucrose gradient analysis shows that Chs3p is present in an inactive form in what may be Golgi compartments but as an active enzyme in other intracellular membrane-bound vesicles, as well as in the plasma membrane. We conclude that Chs3p-dependent chitin synthesis in S. cerevisiae is regulated both by the levels of intermediates of the UDP-GlcNAc biosynthetic pathway and by an increase in the activity of the enzyme in the plasma membrane" |
| Keywords: | "Acetylglucosamine/analysis/pharmacology Cell Wall/*metabolism Chitin/*biosynthesis Chitin Synthase/genetics/*metabolism Down-Regulation Fungal Proteins/metabolism Gene Deletion Gene Expression Profiling Gene Expression Regulation, Fungal Genotype Glucosam;" |
| Notes: | "MedlineBulik, Dorota A Olczak, Mariusz Lucero, Hector A Osmond, Barbara C Robbins, Phillips W Specht, Charles A eng GM31318/GM/NIGMS NIH HHS/ R01 GM031318/GM/NIGMS NIH HHS/ AI44070/AI/NIAID NIH HHS/ R01 AI025780/AI/NIAID NIH HHS/ AI25780/AI/NIAID NIH HHS/ R01 AI044070/AI/NIAID NIH HHS/ Research Support, U.S. Gov't, P.H.S. 2003/10/14 Eukaryot Cell. 2003 Oct; 2(5):886-900. doi: 10.1128/EC.2.5.886-900.2003" |
