| Title: | Glycosylation and structure of the yeast MF alpha 1 alpha-factor precursor is important for efficient transport through the secretory pathway |
| Author(s): | Caplan S; Green R; Rocco J; Kurjan J; |
| Address: | "Department of Biological Sciences, Columbia University, New York, New York 10027" |
| DOI: | 10.1128/jb.173.2.627-635.1991 |
| ISSN/ISBN: | 0021-9193 (Print) 1098-5530 (Electronic) 0021-9193 (Linking) |
| Abstract: | "The MF alpha 1 gene encodes a precursor, prepro-alpha-factor, that undergoes several proteolytic processing steps within the classical secretory pathway to produce the mature peptide pheromone, alpha-factor. To investigate the role of structural features of the MF alpha 1 precursor in alpha-factor production, we analyzed the effect of mf alpha 1 mutations that alter precursor structure in a number of ways. These mutations resulted in decreased alpha-factor secretion and intracellular accumulation of pro-alpha-factor. With the exception of the mutant lacking all three N glycosylation sites, the pro-alpha-factor forms that accumulated were core glycosylated but had not yet undergone the addition of outer chain carbohydrate. The delay, therefore, occurred at a step prior to the first proteolytic processing step involved in maturation of the precursor and was probably due to inefficient endoplasmic reticulum-to-Golgi transport. Elimination of all three N-glycosylation sites caused a delay in disappearance of intracellular precursor, and alpha-factor secretion was also slowed. These data indicate that N glycosylation is important but not essential for transport of the precursor through the secretory pathway. The decreased alpha-factor secretion and increased precursor accumulation seen with many different structural changes of pro-alpha-factor indicate that the secretory pathway is extremely sensitive to changes in precursor structure. This sensitivity could cause inefficient secretion of heterologous proteins and hybrids between MF alpha 1 and heterologous proteins in yeast cells" |
| Keywords: | "Amino Acid Sequence Base Sequence Genes, Fungal Glycosylation Kinetics Mating Factor Molecular Sequence Data Mutagenesis, Site-Directed Oligonucleotide Probes Peptides/*genetics/metabolism Protein Precursors/*genetics *Protein Processing, Post-Translation;" |
| Notes: | "MedlineCaplan, S Green, R Rocco, J Kurjan, J eng GM 38501/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 1991/01/01 J Bacteriol. 1991 Jan; 173(2):627-35. doi: 10.1128/jb.173.2.627-635.1991" |
