Molecular Biology of the Cell click for CBE Life Science Education Page

Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Brizzio, V.
Right arrow Articles by Rose, M. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Brizzio, V.
Right arrow Articles by Rose, M. D.

Vol. 10, Issue 3, 609-626, March 1999

Genetic Interactions between KAR7/SEC71, KAR8/JEM1, KAR5, and KAR2 during Nuclear Fusion in Saccharomyces cerevisiae

Valeria Brizzio,*dagger Waheeda Khalfan,* Don Huddler,* Christopher T. Beh,*Dagger Søren S.L. Andersen,*§ Martin Latterich,parallel and Mark D. Rose*

 *Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544-1014; and  parallel Molecular Biology and Virology Laboratory, The Salk Institute, La Jolla, California 92037-109

During mating of Saccharomyces cerevisiae, two nuclei fuse to produce a single diploid nucleus. Two genes, KAR7 and KAR8, were previously identified by mutations that cause defects in nuclear membrane fusion. KAR7 is allelic to SEC71, a gene involved in protein translocation into the endoplasmic reticulum. Two other translocation mutants, sec63-1 and sec72Delta , also exhibited moderate karyogamy defects. Membranes from kar7/sec71Delta and sec72Delta , but not sec63-1, exhibited reduced membrane fusion in vitro, but only at elevated temperatures. Genetic interactions between kar7 and kar5 mutations were suggestive of protein-protein interactions. Moreover, in sec71 mutants, Kar5p was absent from the SPB and was not detected by Western blot or immunoprecipitation of pulse-labeled protein. KAR8 is allelic to JEMI, encoding an endoplasmic reticulum resident DnaJ protein required for nuclear fusion. Overexpression of KAR8/JEM1 (but not SEC63) strongly suppressed the mating defect of kar2-1, suggesting that Kar2p interacts with Kar8/Jem1p for nuclear fusion. Electron microscopy analysis of kar8 mutant zygotes revealed a nuclear fusion defect different from kar2, kar5, and kar7/sec71 mutants. Analysis of double mutants suggested that Kar5p acts before Kar8/Jem1p. We propose the existence of a nuclear envelope fusion chaperone complex in which Kar2p, Kar5p, and Kar8/Jem1p are key components and Sec71p and Sec72p play auxiliary roles.

   Present addresses: dagger Millennium Pharmaceuticals, Cambridge, MA 02139; Dagger Department of Molecular and Cellular Biology, University of California, Berkeley, CA 94720; and §Department of Neurobiology, University of California at San Diego, La Jolla, CA 92093-0357.
   Corresponding author. E-mail address: mrose{at}molbio.princeton.edu.

Molecular Biology of the Cell
Vol. 10, 609-626, March 1999
Copyright © 1999 by The American Society for Cell Biology


This article has been cited by other articles:


Home page
 Mol. Biol. CellHome page
P. Melloy, S. Shen, E. White, and M. D. Rose
Distinct Roles for Key Karyogamy Proteins during Yeast Nuclear Fusion
Mol. Biol. Cell, September 1, 2009; 20(17): 3773 - 3782.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Biol. CellHome page
S. Shen, C. E. Tobery, and M. D. Rose
Prm3p Is a Pheromone-induced Peripheral Nuclear Envelope Protein Required for Yeast Nuclear Fusion
Mol. Biol. Cell, May 1, 2009; 20(9): 2438 - 2450.
[Abstract] [Full Text] [PDF]

Home page
 GENES CELLSHome page
S.-i. Nishikawa, A. Hirata, and T. Endo
Nuclear inner membrane fusion facilitated by yeast Jem1p is required for spindle pole body fusion but not for the first mitotic nuclear division during yeast mating.
Genes Cells, November 1, 2008; 13(11): 1185 - 1195.
[Abstract] [Full Text] [PDF]

Home page
 GENES CELLSHome page
T. Makio, S.-i. Nishikawa, T. Nakayama, H. Nagai, and T. Endo
Identification and characterization of a Jem1p ortholog of Candida albicans: dissection of Jem1p functions in karyogamy and protein quality control in Saccharomyces cerevisiae
Genes Cells, October 1, 2008; 13(10): 1015 - 1026.
[Abstract] [Full Text] [PDF]

Home page
 Plant Cell PhysiolHome page
M. Yamamoto, D. Maruyama, T. Endo, and S.-i. Nishikawa
Arabidopsis thaliana Has a Set of J Proteins in the Endoplasmic Reticulum that are Conserved from Yeast to Animals and Plants
Plant Cell Physiol., October 1, 2008; 49(10): 1547 - 1562.
[Abstract] [Full Text] [PDF]

Home page
 JCBHome page
P. Melloy, S. Shen, E. White, J. R. McIntosh, and M. D. Rose
Nuclear fusion during yeast mating occurs by a three-step pathway
J. Cell Biol., November 19, 2007; 179(4): 659 - 670.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
M. F. Portereiko, L. Sandaklie-Nikolova, A. Lloyd, C. A. Dever, D. Otsuga, and G. N. Drews
NUCLEAR FUSION DEFECTIVE1 Encodes the Arabidopsis RPL21M Protein and Is Required for Karyogamy during Female Gametophyte Development and Fertilization
Plant Physiology, July 1, 2006; 141(3): 957 - 965.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Biol. CellHome page
D. Poteryaev, J. M. Squirrell, J. M. Campbell, J. G. White, and A. Spang
Involvement of the Actin Cytoskeleton and Homotypic Membrane Fusion in ER Dynamics in Caenorhabditis elegans
Mol. Biol. Cell, May 1, 2005; 16(5): 2139 - 2153.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
B. Kroczynska, C. M. Evangelista, S. S. Samant, E. C. Elguindi, and S. Y. Blond
The SANT2 Domain of the Murine Tumor Cell DnaJ-like Protein 1 Human Homologue Interacts with {alpha}1-Antichymotrypsin and Kinetically Interferes with Its Serpin Inhibitory Activity
J. Biol. Chem., March 19, 2004; 279(12): 11432 - 11443.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
S.-i. Nishikawa, Y. Terazawa, T. Nakayama, A. Hirata, T. Makio, and T. Endo
Nep98p Is a Component of the Yeast Spindle Pole Body and Essential for Nuclear Division and Fusion
J. Biol. Chem., March 7, 2003; 278(11): 9938 - 9943.
[Abstract] [Full Text] [PDF]

Home page
 Plant CellHome page
C. A. Christensen, S. W. Gorsich, R. H. Brown, L. G. Jones, J. Brown, J. M. Shaw, and G. N. Drews
Mitochondrial GFA2 Is Required for Synergid Cell Death in Arabidopsis
PLANT CELL, September 1, 2002; 14(9): 2215 - 2232.
[Abstract] [Full Text] [PDF]

Home page
 J. Cell Sci.Home page
A. Matynia, S. S. Salus, and S. Sazer
Three proteins required for early steps in the protein secretory pathway also affect nuclear envelope structure and cell cycle progression in fission yeast
J. Cell Sci., January 15, 2002; 115(2): 421 - 431.
[Abstract] [Full Text] [PDF]

Home page
 JCBHome page
S.-i. Nishikawa, S. W. Fewell, Y. Kato, J. L. Brodsky, and T. Endo
Molecular Chaperones in the Yeast Endoplasmic Reticulum Maintain the Solubility of Proteins for Retrotranslocation and Degradation
J. Cell Biol., May 28, 2001; 153(5): 1061 - 1070.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Biol. CellHome page
S. Wittke, M. Dünnwald, and N. Johnsson
Sec62p, A Component of the Endoplasmic Reticulum Protein Translocation Machinery, Contains Multiple Binding Sites for the Sec-Complex
Mol. Biol. Cell, November 1, 2000; 11(11): 3859 - 3871.
[Abstract] [Full Text]

Home page
 Mol. Biol. CellHome page
A.-L. Hänninen, M. Simola, N. Saris, and M. Makarow
The Cytoplasmic Chaperone Hsp104 Is Required for Conformational Repair of Heat-denatured Proteins in the Yeast Endoplasmic Reticulum
Mol. Biol. Cell, November 1, 1999; 10(11): 3623 - 3632.
[Abstract] [Full Text]

Home page
 J. Biol. Chem.Home page
M. Yu, R. H. A. Haslam, and D. B. Haslam
HEDJ, an Hsp40 Co-chaperone Localized to the Endoplasmic Reticulum of Human Cells
J. Biol. Chem., August 4, 2000; 275(32): 24984 - 24992.
[Abstract] [Full Text] [PDF]


Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]