Current Genetics

, Volume 53, Issue 4, pp 235–247

Characterization of MYR1, a dosage suppressor of YPT6 and RIC1 deficient mutants

  • Alexander Georgiev
  • Arunas Leipus
  • Ida Olsson
  • Jean-Marc Berrez
  • Ann Mutvei
Research Article

DOI: 10.1007/s00294-008-0183-0

Cite this article as:
Georgiev, A., Leipus, A., Olsson, I. et al. Curr Genet (2008) 53: 235. doi:10.1007/s00294-008-0183-0

Abstract

Membrane traffic is tightly regulated and the Rab protein family of small GTPases plays a central role in this regulation. One member of this family is the Saccharomyces cerevisae protein Ypt6. To search for new genes interacting with Ypt6-related pathways, we performed a genetic screen for high copy suppressors of ypt6Δ temperature sensitivity at 35°C. Among the suppressors, MYR1 was also able to suppress the temperature sensitive mutant lacking Ric1, a subunit of the Ypt6 guanine exchanging factor complex Ric1/Rgp1. Myr1 is characterized by a coiled coil region and a GYF domain, a protein module binding proline-rich sequences. Myr1 is able to bind membranes but is also associated with larger structures insoluble in Triton X-100. By immunofluorescence, Myr1 shows a network-like pattern as well as small foci. Overexpression of Myr1 influences nuclear envelope morphology and high levels are lethal. This lethality is rescued when the N-terminal region, containing the GYF domain, is deleted. The transcription profile of a myr1Δ strain shows effects on genes involved in nuclear migration, Ras signalling and transcription. Taken together, these results suggest that Myr1 is a novel factor linked to the secretory pathway and important cellular regulatory mechanisms.

Keywords

Ypt6 Ric1 GYF domain Membrane traffic Coiled coil Yeast Myr1 

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Alexander Georgiev
    • 1
    • 3
  • Arunas Leipus
    • 2
  • Ida Olsson
    • 1
  • Jean-Marc Berrez
    • 1
  • Ann Mutvei
    • 1
  1. 1.School of Life SciencesSödertörns HögskolaHuddingeSweden
  2. 2.Department of BiochemistryUmeå UniversityUmeåSweden
  3. 3.Department of Biochemistry and BiophysicsStockholm UniversityStockholmSweden