Bio

Professional Education


  • Ph.D., Rockefeller University, Biology (2011)
  • B.S., Bradley University, Biology and Psychology (2002)
  • Post-Bac IRTA, National Institutes of Health, Retrotransposons (2004)

Stanford Advisors


Publications

Journal Articles


  • De Novo Growth Zone Formation from Fission Yeast Spheroplasts PLOS ONE Kelly, F. D., Nurse, P. 2011; 6 (12)

    Abstract

    Eukaryotic cells often form polarized growth zones in response to internal or external cues. To understand the establishment of growth zones with specific dimensions we used fission yeast, which grows as a rod-shaped cell of near-constant width from growth zones located at the cell tips. Removing the cell wall creates a round spheroplast with a disorganized cytoskeleton and depolarized growth proteins. As spheroplasts recover, new growth zones form that resemble normal growing cell tips in shape and width, and polarized growth resumes. Regulators of the GTPase Cdc42, which control width in exponentially growing cells, also control spheroplast growth zone width. During recovery the Cdc42 scaffold Scd2 forms a polarized patch in the rounded spheroplast, demonstrating that a growth zone protein can organize independent of cell shape. Rga4, a Cdc42 GTPase activating protein (GAP) that is excluded from cell tips, is initially distributed throughout the spheroplast membrane, but is excluded from the growth zone after a stable patch of Scd2 forms. These results provide evidence that growth zones with normal width and protein localization can form de novo through sequential organization of cellular domains, and that the size of these growth zones is genetically controlled, independent of preexisting cell shape.

    View details for DOI 10.1371/journal.pone.0027977

    View details for Web of Science ID 000298370400008

    View details for PubMedID 22194800

  • Spatial control of Cdc42 activation determines cell width in fission yeast MOLECULAR BIOLOGY OF THE CELL Kelly, F. D., Nurse, P. 2011; 22 (20): 3801-3811

    Abstract

    The fission yeast Schizosaccharomyces pombe is a rod-shaped cell that grows by linear extension at the cell tips, with a nearly constant width throughout the cell cycle. This simple geometry makes it an ideal system for studying the control of cellular dimensions. In this study, we carried out a near-genome-wide screen for mutants wider than wild-type cells. We found 11 deletion mutants that were wider; seven of the deleted genes are implicated in the control of the small GTPase Cdc42, including the Cdc42 guanine nucleotide exchange factor (GEF) Scd1 and the Cdc42 GTPase-activating protein (GAP) Rga4. Deletions of rga4 and scd1 had additive effects on cell width, and the proteins localized independently of one another, with Rga4 located at the cell sides and Scd1 at the cell tips. Activated Cdc42 localization is altered in rga4?, scd1?, and scd2? mutants. Delocalization and ectopic retargeting experiments showed that the localizations of Rga4 and Scd1 are crucial for their roles in determining cell width. We propose that the GAP Rga4 and the GEF Scd1 establish a gradient of activated Cdc42 within the cellular tip plasma membrane, and it is this gradient that determines cell growth-zone size and normal cell width.

    View details for DOI 10.1091/mbc.E11-01-0057

    View details for Web of Science ID 000296346600006

    View details for PubMedID 21849474

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