The Observation of PlcA Mutation and Localization in Aspergillus nidulans

Abstract

To know the function of the plcA gene, which encodes a putative phosphoinositide-specific phospholipase C, in a model filamentous fungus Aspergillus nidulans, it was disrupted thorough homologous recombination and examined. The germination rate of Delta plcA was reduced by approximately 65% and germination of Delta plcA at a lower temperature (25 degrees C) was much slower than germination under normal conditions (37 degrees C), suggesting the plcA is responsible for cold-sensitivity. The hyphal growth of Delta plcA was slightly reduced at 37 degrees C and conspicuously reduced at 25 degrees C. While germinating Delta plcA formed giant swollen spores, and generated short and thick hyphae. The results of the nuclear examination of Delta plcA showed nuclear division with mis-segregation, and the rate of nuclear division was lower than that of wild type at both 25 degrees C and 37 degrees C. The results of this study showed that plcA is localized to the nucleus through intracellular calcium signaling in A. nidulans. The abnormal nuclear division, resulting from plcA gene deletion, affects conidiation in asexual development. Taken together, these results suggested that plcA is required for normal vegetative growth, morphogenesis, conidiation, and nuclear division in A. nidulans.