A component of the septation initiation network complex, AaSepM, is involved in multiple cellulose-responsive signaling pathways in Aspergillus aculeatus
A component of the septation initiation network complex, AaSepM, is involved in multiple cellulose-responsive signaling pathways in Aspergillus aculeatus
复制标题
分隔启动网络复合体的一个组成部分 AaSepM 参与棘孢曲霉中的多种纤维素响应信号通路
DOI：
10.1007/s00253-021-11110-7
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发表时间：
2021
影响因子：
5
通讯作者：
Tani Shuji
中科院分区：
文献类型：
--
作者：
Tsumura Ryosuke;Sawada Kazumi;Kunitake Emi;Sumitani Jun-ichi;Kawaguchi Takashi;Tani Shuji
鳗鱼体内的各种碳水化合物活性酶是对生理诱导物的应答，这些酶在转录水平上受到调控。为了阐明曲霉的诱导机制，我们从大约10，000株棘孢曲霉T-DNA插入突变体中筛选了参与纤维素应答诱导的新调控因子。利用携带乳清酸核苷5′-单磷酸脱羧酶基因（pyrG）的宿主菌构建了T-DNA插入突变体文库。因此，通过针对5-氟乳清酸（5-FOA）的反向选择，阳性筛选纤维素应答诱导缺陷的候选突变体。在不到200个5-FOA抗性突变体中，有一个突变体，其T-DNA插入到AaseP M基因座上，降低了响应纤维素的bhi I表达。由于AaSepM与粟酒裂殖酵母Cdc 14 p（E值为2 e-20，同源性为33%）相似，是分隔起始网络（SIN）复合体的一个组成部分，因此我们构建了一个AasepM缺失突变体（ΔAasepM）。我们分析了纤维素酶和木聚糖酶基因在ΔAasepM中响应纤维素、分隔和分生孢子的表达。AasepM缺失导致A. aculeatus但不影响菌丝在基本培养基上的生长。我们还证实了AaSepM参与了纤维素酶和木聚糖酶基因的多个纤维素响应信号通路，这些信号通路受ManR依赖性、XlnR依赖性以及ManR和XlnR非依赖性信号通路的控制。关键点·已鉴定出一种新的纤维素分解基因表达调节因子。·AaSepM参与A. aculeatus。AasepM参与多种纤维素应答信号通路。
AbstractVarious carbohydrate-active enzymes inAspergillusare produced in response to physiological inducers, which is regulated at the transcriptional level. To elucidate the induction mechanisms inAspergillus, we screened for new regulators involved in cellulose-responsive induction from approximately 10,000Aspergillus aculeatusT-DNA-inserted mutants. We constructed the T-DNA-inserted mutant library using the host strain harboring the orotidine 5′-monophosphate decarboxylase gene (pyrG) under the control of the FIII-avicelase gene (cbhI) promoter. Thus, candidate mutants deficient in cellulose-responsive induction were positively screened via counter selection against 5-fluoroorotic acid (5-FOA). Among less than two hundred 5-FOA-resistant mutants, one mutant that the T-DNA inserted into theAasepMlocus reduced thecbhIexpression in response to cellulose. Since AaSepM is similar toSchizosaccharomyces pombeCdc14p (E-value, 2e-20; identities, 33%), which is a component of the septation initiation network (SIN)-complex, we constructed anAasepMdeletion mutant (ΔAasepM). We analyzed the expression of cellulase and xylanase genes in response to cellulose, septation, and conidiation in ΔAasepM. TheAasepMdeletion leads to delayed septation and decreased formation of the conidium chain inA. aculeatusbut does not affect hyphal growth on minimal media. We also confirmed AaSepM’s involvement in multiple cellulose-responsive signaling pathways of cellulase and xylanase genes under the control of the ManR-dependent, XlnR-dependent, and ManR- and XlnR-independent signaling pathways.Key points•A new regulator for cellulolytic gene expression has been identified.•AaSepM is involved in septation and conidiation in A. aculeatus.•AasepM is involved in multiple cellulose-responsive signaling pathways.