Pongsunk Supinya, Andrianopoulos Alex, Chaiyaroj Sansanee C
Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand.
Fungal Genet Biol. 2005 Nov;42(11):893-903. doi: 10.1016/j.fgb.2005.07.002. Epub 2005 Oct 13.
Problems can arise in studying the regulation of transcription in fungi if gene disruption is employed to evaluate the role of essential transcription factors. Herein, we have developed a method to characterize the essential genes of Penicillium marneffei. This has been used to examine the significance of P. marneffei TATA-binding protein (TBP) in growth and development. Strains in which the expression of TbpA could be regulated were constructed by placing tbpA under the control of the xylP promoter. The construct was introduced into P. marneffei and the resulting strains were used to produce P. marneffei tbpA deletion strains. Phenotypic examination of growth of the tbpA overexpressing strains revealed that high levels of TbpA expression inhibit fungal growth at conidial germination in both filamentous and yeast forms. Under repressing conditions, the tbpA deletion strains failed to grow at 25 degrees C whilst showing reduced growth at 37 degrees C. The results suggested that TbpA is essential for P. marneffei filamentous growth, but plays a less significant role in growth and development during the yeast phase.
如果采用基因敲除来评估必需转录因子的作用，那么在研究真菌转录调控时可能会出现问题。在此，我们开发了一种方法来鉴定马尔尼菲青霉的必需基因。该方法已用于检验马尔尼菲青霉TATA结合蛋白（TBP）在生长和发育中的重要性。通过将tbpA置于xylP启动子的控制下，构建了可调控TbpA表达的菌株。将该构建体导入马尔尼菲青霉，所得菌株用于产生马尔尼菲青霉tbpA缺失菌株。对tbpA过表达菌株生长的表型检查表明，高水平的TbpA表达在丝状和酵母形式的分生孢子萌发时均抑制真菌生长。在抑制条件下，tbpA缺失菌株在25℃下无法生长，而在37℃下生长减缓。结果表明，TbpA对马尔尼菲青霉的丝状生长至关重要，但在酵母阶段的生长和发育中作用较小。
