This Article
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 arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sengar, A. S.
Right arrow Articles by Young, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sengar, A. S.
Right arrow Articles by Young, D.

 Previous Article  |  Next Article 

Mol. Cell. Biol., 07 1997, 3508-3519, Vol 17, No. 7
Copyright © 1997, American Society for Microbiology

Mkh1, a MEK kinase required for cell wall integrity and proper response to osmotic and temperature stress in Schizosaccharomyces pombe

AS Sengar, NA Markley, NJ Marini and D Young
Department of Medical Biochemistry, University of Calgary Health Science Centre, Alberta, Canada.

We have identified a Schizosaccharomyces pombe gene, mkh1, that encodes a MEK kinase (MEKK) homolog. The coding region of mkh1 is contained within a single exon encoding a 1,116-amino-acid protein. The putative catalytic domain of Mkh1 is 54% identical to the catalytic domain of S. cerevisiae Bck1, the most closely related protein. Deletion of mkh1 did not significantly affect cell growth or division under standard conditions. However, mkh1delta cell growth was inhibited by high KCl or NaCl concentrations. mkh1delta cells required a longer time to reenter the cell cycle after prolonged stationary-phase arrest. Also, mkh1delta cells exhibited a round cell shape, while overexpression of Mkh1 resulted in an elongated cell shape. mkh1delta cells exhibited a more dramatic phenotype when grown in nutrient-limiting conditions at high temperature or in hyperosmotic medium. In such conditions, completion of cytokinesis was inhibited, resulting in the growth of pseudohyphal filaments with multiple septa and nuclei. Also, mkh1delta cells were hypersensitive to beta-glucanase treatment. Together these results suggest that Mkh1 regulates cell morphology, cell wall integrity, salt resistance, cell cycle reentry from stationary-phase arrest, and filamentous growth in response to stress. These phenotypes are essentially identical to those exhibited by cells lacking Pmk1/Spm1, a recently identified mitogen-activated protein kinase. Our evidence suggests that Pmk1/Spm1 acts downstream from Mkh1 in a common pathway. Our results also suggest that Mkh1 and Pck2 act independently to maintain cell wall integrity, cell morphology, and salt resistance but act in opposition to regulate filamentous growth.


This article has been cited by other articles:

  • Garcia, P., Tajadura, V., Sanchez, Y. (2009). The Rho1p Exchange Factor Rgf1p Signals Upstream from the Pmk1 Mitogen-activated Protein Kinase Pathway in Fission Yeast. Mol. Biol. Cell 20: 721-731 [Abstract] [Full Text]  
  • Robertson, A. M., Hagan, I. M. (2008). Stress-regulated kinase pathways in the recovery of tip growth and microtubule dynamics following osmotic stress in S. pombe. J. Cell Sci. 121: 4055-4068 [Abstract] [Full Text]  
  • Codlin, S., Haines, R. L., Jemima, J., Burden, E., Mole, S. E. (2008). btn1 affects cytokinesis and cell-wall deposition by independent mechanisms, one of which is linked to dysregulation of vacuole pH. J. Cell Sci. 121: 2860-2870 [Abstract] [Full Text]  
  • Takada, H., Nishimura, M., Asayama, Y., Mannse, Y., Ishiwata, S., Kita, A., Doi, A., Nishida, A., Kai, N., Moriuchi, S., Tohda, H., Giga-Hama, Y., Kuno, T., Sugiura, R. (2007). Atf1 Is a Target of the Mitogen-activated Protein Kinase Pmk1 and Regulates Cell Integrity in Fission Yeast. Mol. Biol. Cell 18: 4794-4802 [Abstract] [Full Text]  
  • Madrid, M., Nunez, A., Soto, T., Vicente-Soler, J., Gacto, M., Cansado, J. (2007). Stress-activated Protein Kinase-mediated Down-Regulation of the Cell Integrity Pathway Mitogen-activated Protein Kinase Pmk1p by Protein Phosphatases. Mol. Biol. Cell 18: 4405-4419 [Abstract] [Full Text]  
  • Ma, Y., Kuno, T., Kita, A., Asayama, Y., Sugiura, R. (2006). Rho2 Is a Target of the Farnesyltransferase Cpp1 and Acts Upstream of Pmk1 Mitogen-activated Protein Kinase Signaling in Fission Yeast. Mol. Biol. Cell 17: 5028-5037 [Abstract] [Full Text]  
  • Madrid, M., Soto, T., Khong, H. K., Franco, A., Vicente, J., Perez, P., Gacto, M., Cansado, J. (2006). Stress-induced Response, Localization, and Regulation of the Pmk1 Cell Integrity Pathway in Schizosaccharomyces pombe. J. Biol. Chem. 281: 2033-2043 [Abstract] [Full Text]  
  • Bimbo, A., Jia, Y., Poh, S. L., Karuturi, R. K. M., den Elzen, N., Peng, X., Zheng, L., O'Connell, M., Liu, E. T., Balasubramanian, M. K., Liu, J. (2005). Systematic Deletion Analysis of Fission Yeast Protein Kinases. Eukaryot Cell 4: 799-813 [Abstract] [Full Text]  
  • Torbett, N. E., Casamassima, A., Parker, P. J. (2003). Hyperosmotic-induced Protein Kinase N 1 Activation in a Vesicular Compartment Is Dependent upon Rac1 and 3-Phosphoinositide-dependent Kinase 1. J. Biol. Chem. 278: 32344-32351 [Abstract] [Full Text]  
  • Huang, T. Y., Markley, N. A., Young, D. (2003). Nak1, an Essential Germinal Center (GC) Kinase Regulates Cell Morphology and Growth in Schizosaccharomyces pombe. J. Biol. Chem. 278: 991-997 [Abstract] [Full Text]  
  • Jang, M. J., Jwa, M., Kim, J.-H., Song, K. (2002). Selective Inhibition of MAPKK Wis1 in the Stress-activated MAPK Cascade of Schizosaccharomyces pombe by Novel Berberine Derivatives. J. Biol. Chem. 277: 12388-12395 [Abstract] [Full Text]  
  • Meijer, M., Karimi-Busheri, F., Huang, T. Y., Weinfeld, M., Young, D. (2002). Pnk1, a DNA Kinase/Phosphatase Required for Normal Response to DNA Damage by gamma -Radiation or Camptothecin in Schizosaccharomyces pombe. J. Biol. Chem. 277: 4050-4055 [Abstract] [Full Text]  
  • Bandyopadhyay, A., Matsumoto, T., Maitra, U. (2000). Fission Yeast Int6 Is Not Essential for Global Translation Initiation, but Deletion of int6+ Causes Hypersensitivity to Caffeine and Affects Spore Formation. Mol. Biol. Cell 11: 4005-4018 [Abstract] [Full Text]  
  • Loewith, R, Hubberstey, A, Young, D (2000). Skh1, the MEK component of the mkh1 signaling pathway in Schizosaccharomyces pombe. J. Cell Sci. 113: 153-160 [Abstract]  
  • Nosanchuk, J. D., Cleare, W., Franzot, S. P., Casadevall, A. (1999). Amphotericin B and Fluconazole Affect Cellular Charge, Macrophage Phagocytosis, and Cellular Morphology of Cryptococcus neoformans at Subinhibitory Concentrations. Antimicrob. Agents Chemother. 43: 233-239 [Abstract] [Full Text]  
  • Arellano, M, Valdivieso, M., Calonge, T., Coll, P., Duran, A, Perez, P (1999). Schizosaccharomyces pombe protein kinase C homologues, pck1p and pck2p, are targets of rho1p and rho2p and differentially regulate cell integrity. J. Cell Sci. 112: 3569-3578 [Abstract]  
  • Gustin, M. C., Albertyn, J., Alexander, M., Davenport, K. (1998). MAP Kinase Pathways in the Yeast Saccharomyces cerevisiae. Microbiol. Mol. Biol. Rev. 62: 1264-1300 [Abstract] [Full Text]