The Pochonia chlamydosporia serine protease gene vcp1 is subject to regulation by carbon, nitrogen and pH: implications for nematode biocontrol.
The Pochonia chlamydosporia serine protease gene vcp1 is subject to regulation by carbon, nitrogen and pH: implications for nematode biocontrol.
复制标题
DOI：
10.1371/journal.pone.0035657
复制
发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Hirsch PR
中科院分区：
文献类型：
--
作者：
Ward E;Kerry BR;Manzanilla-López RH;Mutua G;Devonshire J;Kimenju J;Hirsch PR
真菌 Pochonia chlamydosporia 的碱性丝氨酸蛋白酶 VCP1 属于枯草杆菌蛋白酶家族，参与线虫和昆虫宿主的感染。它参与感染过程的早期，去除线虫卵的外部蛋白质卵黄膜。尽管了解营养物质和其他因素如何影响其表达对于确保其作为生物防治剂的功效至关重要，但人们对该基因的调控知之甚少。本文提供了有关vcp1表达调控的新信息。对 30 个分离株中该基因上游调控区的序列分析表明，它高度保守，并且包含受碳、氮和 pH 调控的基因特征的序列基序。表达研究、监测酶活性和 mRNA，证实这些因素影响 VCP1 的产生。正如预期的那样，葡萄糖降低了 VCP1 的表达，氯化铵在几个小时内也能降低 VCP1 的表达。然而，令人惊讶的是，在存在氯化铵的情况下，到 24 小时，大多数分离株的 VCP1 水平均有所增加。环境 pH 值也调节 VCP1 的表达，大多数分离株在碱性条件下产生更多的 VCP1。具有独特上游序列（包括变异调控基序谱）的一种分离株的反应存在一些差异。冷冻扫描电子显微镜研究表明，线虫卵的存在会刺激厚垣孢子虫产生 VCP1，但仅限于两者密切接触的情况。总体而言，结果表明，根际/卵团环境中易代谢的碳源和不利的 pH 值可能会损害厚垣孢子线虫的寄生。然而，与之前使用其他食线虫和昆虫病原真菌的迹象相反，硝酸铵（例如来自肥料）在某些情况下可能会增强生物防治潜力。
The alkaline serine protease VCP1 of the fungus Pochonia chlamydosporia belongs to a family of subtilisin-like enzymes that are involved in infection of nematode and insect hosts. It is involved early in the infection process, removing the outer proteinaceous vitelline membrane of nematode eggs. Little is known about the regulation of this gene, even though an understanding of how nutrients and other factors affect its expression is critical for ensuring its efficacy as a biocontrol agent. This paper provides new information on the regulation of vcp1 expression. Sequence analysis of the upstream regulatory region of this gene in 30 isolates revealed that it was highly conserved and contained sequence motifs characteristic of genes that are subject to carbon, nitrogen and pH-regulation. Expression studies, monitoring enzyme activity and mRNA, confirmed that these factors affect VCP1 production. As expected, glucose reduced VCP1 expression and for a few hours so did ammonium chloride. Surprisingly, however, by 24 h VCP1 levels were increased in the presence of ammonium chloride for most isolates. Ambient pH also regulated VCP1 expression, with most isolates producing more VCP1 under alkaline conditions. There were some differences in the response of one isolate with a distinctive upstream sequence including a variant regulatory-motif profile. Cryo-scanning electron microscopy studies indicated that the presence of nematode eggs stimulates VCP1 production by P. chlamydosporia, but only where the two are in close contact. Overall, the results indicate that readily-metabolisable carbon sources and unfavourable pH in the rhizosphere/egg-mass environment may compromise nematode parasitism by P. chlamydosporia. However, contrary to previous indications using other nematophagous and entomopathogenic fungi, ammonium nitrate (e.g. from fertilizers) may enhance biocontrol potential in some circumstances.
登录
查看更多内容
影响因子：
3.6
作者：
KULMBURG, P;MATHIEU, M;FELENBOK, B
通讯作者：
FELENBOK, B
影响因子：
2.8
作者：
Ahman, J;Ek, B;Tunlid, A
通讯作者：
Tunlid, A
影响因子：
--
作者：
Esteves, Ivania;Peteira, Belkis;Kerry, Brian
通讯作者：
Kerry, Brian
影响因子：
3.5
作者：
ESPESO, EA;PENALVA, MA
通讯作者：
PENALVA, MA
影响因子：
4.9
作者：
Hirsch, PR;Atkins, SD;Kerry, BR
通讯作者：
Kerry, BR