Abstract
A defect in mcb, encoding the cAMP-dependent protein kinase A (PKA) regulatory subunit in Neurospora crassa, which confers an apolar growth phenotype, is accompanied by an increase in PKA activity levels. Both PKA and CRE-1 [a key carbon catabolite repression (CCR) regulator] mediate the cellular response to carbon-source availability. Inactivation of the cre-1 gene resulted in reduced growth rate, abnormal hyphal morphology and altered CCR. Both PKA and CRE-1 affected morphology in a carbon-dependent manner, as fructose suppressed the apolar morphology of the mcb strain and enabled faster growth of the Deltacre-1 mutant. An increase in cre-1 transcript abundance was observed in mcb and a reduction in PKA activity levels was measured in Deltacre-1. CRE-1 is involved in determining PKA-dependent polarity, as an mcb;Deltacre-1 strain displayed partial reestablishment of hyphal polarity. Taken together, our results demonstrate regulatory interactions between PKA and CRE-1 that affect cell polarity in a filamentous fungus.
Original language | English |
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Pages (from-to) | 103-116 |
Number of pages | 14 |
Journal | Experimental Mycology |
Volume | 45 |
Issue number | 2 |
DOIs | |
State | Published - Feb 2008 |
Bibliographical note
Funding Information:We thank S. Seiler and Y. Hadar for their helpful comments and discussions and Yi Liu for providing unpublished data. This research project was supported by The Israel Science Foundation.