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Expression analysis of Candida albicans following a block in mitotic exit

ABSTRACT: Candida albicans demonstrates three main growth morphologies yeast, pseudohyphal and true hyphal forms. Cell separation is distinct in these morphological forms and the process of separation is closely linked to the completion of mitosis and cytokinesis. In Saccharomyces cerevisiae the small GTPase Tem1 is known to initiate the mitotic exit network, a signalling pathway involved in signalling the end of mitosis and initiating cytokinesis and cell separation. We have characterised the role of Tem1 in C. albicans, and demonstrate that it is essential for mitotic exit and cytokinesis, and that this essential function is signalled through the kinase Cdc15. Consistent with its role in activating the mitotic exit network Tem1 localised to spindle pole bodies in a cell cycle dependent manner. Cells depleted of Tem1 displayed highly polarised growth but ultimately fail to complete cytokinesis and re-enter the cell cycle following nuclear division. At the transcriptional level genes downregulated following the depletion of Tem1 where significantly enriched for genes whose expression peaks early in the cell cycle and for those associated with glycolysis. For expression analysis triplicate RNA samples were generated from exponentially growing C. albicans yeast cells and from cells following 8 h inhibition of TEM1 expression. Gene expression was determined using RNA-seq on the Illumina HiSeq 2000 platform.

ORGANISM(S): Candida albicans

SUBMITTER: Steven Bates

PROVIDER: E-GEOD-48650 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Expression analysis of Candida albicans following a block in mitotic exit

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