The Conserved NDR Kinase Orb6 Controls Polarized Cell Growth by Spatial Regulation of the Small GTPase Cdc42

Maitreyi Das, David J. Wiley, Xi Chen, Kavita Shah, Fulvia Verde

Research output: Contribution to journalArticle

55 Scopus citations

Abstract

The conserved NDR kinase regulates cell morphogenesis and polarized cell growth in different eukaryotic cells ranging from yeast to neurons [1-4]. Although studies have unraveled the mechanism of regulation of NDR kinase activity [4], the mechanism of morphology control by NDR and the effectors that mediate NDR function are unknown. Via a chemical genetic approach, we show that the fission yeast NDR homolog, Orb6 kinase, maintains polarized cell growth at the cell tips by spatially regulating the localization of Cdc42 GTPase, a key morphology regulator. Loss of Orb6 kinase activity leads to the recruitment of Cdc42 GTPase and the Cdc42-dependent formin For3, normally found only at the cell tips, to the cell sides. Furthermore, we show that loss of Orb6 kinase activity leads to ectopic lateral localization of the Cdc42 guanine nucleotide exchange factor (GEF) Gef1, but not of the other Cdc42 GEF, Scd1. Consistent with these observations, gef1 deletion suppresses the increased cell diameter phenotype of orb6 mutants. In contrast, the microtubule cytoskeleton and the localization of the microtubule-dependent polarity markers Tea1 and Tea4 are not altered by loss of Orb6 kinase activity. Our findings indicate that the conserved NDR kinase Orb6 regulates cell polarity by spatially restricting the localization and activity of Cdc42 GTPase.

Original languageEnglish (US)
Pages (from-to)1314-1319
Number of pages6
JournalCurrent Biology
Volume19
Issue number15
DOIs
StatePublished - Aug 11 2009

Keywords

  • CELLBIO
  • CELLCYCLE
  • SIGNALING

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'The Conserved NDR Kinase Orb6 Controls Polarized Cell Growth by Spatial Regulation of the Small GTPase Cdc42'. Together they form a unique fingerprint.

  • Cite this