ISOLATION OF A GENE REQUIRED FOR PROGRAMMED INITIATION OF DEVELOPMENT BY ASPERGILLUS-NIDULANS
ISOLATION OF A GENE REQUIRED FOR PROGRAMMED INITIATION OF DEVELOPMENT BY ASPERGILLUS-NIDULANS
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DOI：
10.1128/mcb.12.9.3827
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发表时间：
1992-09-01
影响因子：
5.3
通讯作者：
LEE, BN
中科院分区：
文献类型：
--
作者：
ADAMS, TH;HIDE, WA;LEE, BN
与微生物发育的许多其他情况相反，构巢曲霉分生孢子梗的产生主要是作为生命周期的一个程序性部分启动的，而不是作为对营养缺乏的一种反应。acoD基因座的突变导致“绒毛状”菌落，其似乎比野生型生长得更快，并作为未分化的营养细胞团增殖。我们表明，与野生型菌株不同，acoD缺失突变体在最佳生长条件下不能形成分生孢子梗，但在营养受限的生长条件下可被诱导产生分生孢子。在分生孢子梗发育过程中对acoD的需求发生在brlA（一种主要的发育调节因子）激活之前。acoD转录本在发育诱导前的营养菌丝以及发育中的培养物中均存在。然而，acoD突变的影响只有在发育诱导之后才能被检测到。我们提出acoD的活性主要在转录后水平受到控制，并且它是引导发育特异性变化所必需的，这些变化导致生长抑制以及brlA表达的激活，从而导致分生孢子梗的发育。
In contrast to many other cases in microbial development, Aspergillus nidulans conidiophore production initiates primarily as a programmed part of the life cycle rather than as a response to nutrient deprivation. Mutations in the acoD locus result in "fluffy" colonies that appear to grow faster than the wild type and proliferate as undifferentiated masses of vegetative cells. We show that unlike wild-type strains, acoD deletion mutants are unable to make conidiophores under optimal growth conditions but can be induced to conidiate when growth is nutritionally limited. The requirement for acoD in conidiophore development occurs prior to activation of brlA, a primary regulator of development. The acoD transcript is present both in vegetative hyphae prior to developmental induction and in developing cultures. However, the effects of acoD mutations are detectable only after developmental induction. We propose that acoD activity is primarily controlled at the posttranscriptional level and that it is required to direct developmentally specific changes that bring about growth inhibition and activation of brlA expression to result in conidiophore development.