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Symmetry breaking and the establishment of cell polarity in budding yeast.

ABSTRACT: Cell polarity is typically oriented by external cues such as cell-cell contacts, chemoattractants, or morphogen gradients. In the absence of such cues, however, many cells can spontaneously polarize in a random direction, suggesting the existence of an internal polarity-generating mechanism whose direction can be spatially biased by external cues. Spontaneous 'symmetry-breaking' polarization is likely to involve an autocatalytic process set off by small random fluctuations. Here we review recent work on the nature of the autocatalytic process in budding yeast and on the question of why polarized cells only develop a single 'front'.

SUBMITTER: Johnson JM

PROVIDER: S-EPMC3224179 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Symmetry breaking and the establishment of cell polarity in budding yeast.

Johnson Jayme M JM Jin Meng M Lew Daniel J DJ

Current opinion in genetics & development 20110928 6

Cell polarity is typically oriented by external cues such as cell-cell contacts, chemoattractants, or morphogen gradients. In the absence of such cues, however, many cells can spontaneously polarize in a random direction, suggesting the existence of an internal polarity-generating mechanism whose direction can be spatially biased by external cues. Spontaneous 'symmetry-breaking' polarization is likely to involve an autocatalytic process set off by small random fluctuations. Here we review recent ...[more]

PMID: 21955794

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