Glycobiology, 2000, Vol. 10, No. 7 737-744
© 2000 Oxford University Press
Evidence for interaction of yeast protein kinase C with several subunits of oligosaccharyl transferase
Department of Biochemistry and Cell Biology, and Institute for Cell and Developmental Biology, SUNY at Stony Brook, Stony Brook, New York 11794, USA
Oligosaccharyltransferase (OT) in Saccharomyces cerevisiae is an enzyme complex consisting of 8 transmembrane proteins located in the endoplasmic reticulum (ER). Studies on potential protein–protein interactions in OT using a two-hybrid library screen revealed that protein kinase C (Pkc1p) interacted with the lumenal domains of several OT subunits. Additional genetic experiments revealed that overexpression of two OT subunits rescued the growth defect caused by overexpression of a Pkc1 active site mutant, implying that there are specific genetic interactions between PKC1 and OT. These in vivo findings were complemented by in vitro studies that showed that several of the OT subunits bound to a fusion protein consisting of glutathione S-transferase linked via its C-terminus to Pkc1p. Assays of OT activity, in which glycosylation of a simple acceptor peptide was assayed in microsomes from wild-type and a pkc1 null revealed a 50% reduction in activity in the microsomes from the null strain. In contrast, strains containing null mutations of two other genes known to be downstream of Pkc1p in the PKC1-MAP kinase pathway had a level of OT activity comparable to that of wild-type cells. These in vivo and in vitro experiments suggest that in yeast cells Pkc1p may be involved in regulation of the N-glycosylation of proteins.
1 To whom correspondence should be addressed
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  R. Rodicio, S. Koch, H.-P. Schmitz, and J. J. Heinisch KlRHO1 and KlPKC1 are essential for cell integrity signalling in Kluyveromyces lactis. Microbiology, September 1, 2006; 152(Pt 9): 2635 - 2649. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. H. Black, A. Sanjay, K. van Leyen, B. Lauring, and G. Kreibich Cholesterol and Steroid Synthesizing Smooth Endoplasmic Reticulum of Adrenocortical Cells Contains High Levels of Proteins Associated with the Translocation Channel Endocrinology, October 1, 2005; 146(10): 4234 - 4249. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. E. Levin Cell Wall Integrity Signaling in Saccharomyces cerevisiae Microbiol. Mol. Biol. Rev., June 1, 2005; 69(2): 262 - 291. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Yan, E. Wu, and W. J. Lennarz Studies of yeast oligosaccharyl transferase subunits using the split-ubiquitin system: Topological features and in vivo interactions PNAS, May 17, 2005; 102(20): 7121 - 7126. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Denis and M. S. Cyert Molecular Analysis Reveals Localization of Saccharomyces cerevisiae Protein Kinase C to Sites of Polarized Growth and Pkc1p Targeting to the Nucleus and Mitotic Spindle Eukaryot. Cell, January 1, 2005; 4(1): 36 - 45. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Chavan, M. Rekowicz, and W. Lennarz Insight into Functional Aspects of Stt3p, a Subunit of the Oligosaccharyl Transferase: EVIDENCE FOR INTERACTION OF THE N-TERMINAL DOMAIN OF Stt3p WITH THE PROTEIN KINASE C CASCADE J. Biol. Chem., December 19, 2003; 278(51): 51441 - 51447. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Yan, E. Ahmed, Q. Yan, and W. J. Lennarz New Findings on Interactions among the Yeast Oligosaccharyl Transferase Subunits Using a Chemical Cross-linker J. Biol. Chem., August 29, 2003; 278(35): 33078 - 33087. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H.-P. Schmitz, S. Huppert, A. Lorberg, and J. J. Heinisch Rho5p downregulates the yeast cell integrity pathway J. Cell Sci., January 8, 2002; 115(15): 3139 - 3148. [Abstract] [Full Text] [PDF]
|
|