Analysis of the role of transcription factor VAD-5 in conidiation of Neurospora crassa
Analysis of the role of transcription factor VAD-5 in conidiation of Neurospora crassa
复制标题
转录因子VAD-5在粗糙脉孢菌分生孢子形成中的作用分析
DOI：
10.1016/j.fgb.2012.03.003
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发表时间：
2012-05-01
影响因子：
3
通讯作者：
Li, Shaojie
中科院分区：
文献类型：
--
作者：
Sun, Xianyun;Yu, Luning;Li, Shaojie
分生孢子是许多丝状真菌的主要繁殖方式。粗糙脉孢菌的vad-5基因编码一种类似GAL4的Zn2Cys6转录因子，在先前使用敲除突变体的研究中被认为对分生孢子的形成有贡献。在本研究中，我们通过基因互补证实了vad-5在分生孢子形成中的积极作用。为了了解VAD-5在分生孢子形成中的作用，比较了VAD-5缺失突变株和野生型菌株的数字基因表达谱。在检测到的7559个基因中，有176个基因在vad-5缺失突变体中转录下调，277个基因转录上调，以>；=1倍变化作为截断阈值。在下调的基因中，已知与分生孢子形成有关的四个基因--ffffy、ada-6、rca-1和eas--在时间进程实验中被进一步检测。在分生孢子发育过程中，vad-5缺失突变体中四个基因的转录均低于野生型菌株。对vad-5缺失下调的132个基因的缺失突变体的表型观察表明，17个基因的缺失突变体产生的分生孢子比野生型少。通过对vad-5缺失突变体中上调的211个基因的缺失突变体的表型观察，发现了两种类型的缺失突变。其中一种类型比野生型菌株产生更多的分生孢子，包括先前特征基因CAT-2、CAT-3和SAH-1以及非特征基因NCU07221的缺失突变。代表第二种类型的缺失突变体NCU06302和NCU11090比野生型菌株更早产生分生孢子。根据这些分生孢子表型，我们将NCU07221命名为高产分生孢子-1(HCP-1)，将NCU06302和NCU11090分别命名为早期分生孢子发育-1(ECD-1)和ECD-2。根据本研究的总体结果，我们认为VAD-5通过激活促进分生孢子形成的基因和抑制消极影响分生孢子发育的基因来影响分生孢子的形成。(C)2012 Elsevier Inc.保留所有权利。
Conidiation is the major mode of reproduction in many filamentous fungi. The Neurospora crassa gene vad-5, which encodes a GAL4-like Zn2Cys6 transcription factor, was suggested to contribute to conidiation in a previous study using a knockout mutant. In this study, we confirmed the positive contribution of vad-5 to conidiation by gene complementation. To understand the role of VAD-5 in conidiation, transcriptomic profiles generated by digital gene expression profiling from the vad-5 deletion mutant and the wild-type strain were compared. Among 7559 detected genes, 176 genes were found to be transcriptionally down-regulated and 277 genes transcriptionally upregulated in the vad-5 deletion mutant, using >= 1-fold change as a cutoff threshold. Among the down-regulated genes, four which were already known to be involved in conidiation - fluffy, ada-6, rca-1, and eas - were examined further in a time course experiment. Transcription of each of the four genes in the vad-5 deletion mutant was lower than in the wild-type strain during conidial development. Phenotypic observation of deletion mutants for 132 genes down-regulated by vad-5 deletion revealed that deletion mutants for 17 genes, including fluffy, ada-6, and eas, produced fewer conidia than the wild type. By phenotypic observation of deletion mutants for 211 genes upregulated in the vad-5 deletion mutant, two types of deletion mutants were found. One type, which produced more conidia than the wild-type strain, includes deletion mutants for previously characterized genes cat-2, cat-3, and sah-1 and for a non-characterized gene NCU07221. Deletion mutants of NCU06302 and NCU11090, representing the second type, produced conidia earlier than the wild-type strain. Based on these conidiation phenotypes, we designated NCU07221 as high conidial production-1 (hcp-1) and named NCU06302 and NCU11090 as early conidial development-1 (ecd-1) and ecd-2, respectively. Given the collective results from this study, we propose that VAD-5 exerts an effect on conidiation by activating genes that positively contribute to conidiation as well as by repressing genes that negatively influence conidial development. (C) 2012 Elsevier Inc. All rights reserved.