Purschwitz Janina, Müller Sylvia, Fischer Reinhard
Institute of Applied Biosciences, Applied Microbiology, University of Karlsruhe, Karlsruhe Institute of Technology (KIT), Hertzstrasse 16, 76187, Karlsruhe, Germany.
Mol Genet Genomics. 2009 Jan;281(1):35-42. doi: 10.1007/s00438-008-0390-x. Epub 2008 Oct 21.
Aspergillus nidulans senses red and blue-light and employs a phytochrome and a Neurospora crassa White Collar (WC) homologous system for light perception and transmits this information into developmental decisions. Under light conditions it undergoes asexual development and in the dark it develops sexually. The phytochrome FphA consists of a light sensory domain and a signal output domain, consisting of a histidine kinase and a response regulator domain. Previously it was shown that the phytochrome FphA directly interacts with the WC-2 homologue, LreB and another regulator, VeA. In this paper we mapped the interaction of FphA with LreB to the histidine kinase and the response regulator domain at the C-terminus in vivo using the bimolecular fluorescence complementation assay and in vitro by co-immunoprecipitation. In comparison, VeA interacted with FphA only at the histidine kinase domain. We present evidence that VeA occurs as a phosphorylated and a non-phosphorylated form in the cell. The phosphorylation status of the protein was independent of the light receptors FphA, LreB and the WC-1 homologue LreA.
构巢曲霉能感知红光和蓝光，并利用一种光敏色素和一种与粗糙脉孢菌白领（WC）同源的系统进行光感知，并将此信息转化为发育决策。在光照条件下，它进行无性发育，在黑暗中则进行有性发育。光敏色素FphA由一个光感应结构域和一个信号输出结构域组成，信号输出结构域由一个组氨酸激酶和一个反应调节结构域组成。此前已表明，光敏色素FphA直接与WC-2同源物LreB以及另一种调节因子VeA相互作用。在本文中，我们使用双分子荧光互补试验在体内以及通过免疫共沉淀在体外将FphA与LreB的相互作用定位到C端的组氨酸激酶和反应调节结构域。相比之下，VeA仅在组氨酸激酶结构域与FphA相互作用。我们提供的证据表明，VeA在细胞中以磷酸化和非磷酸化两种形式存在。该蛋白的磷酸化状态与光受体FphA、LreB以及WC-1同源物LreA无关。
