title: Physical association of the WC-1 photoreceptor and the histone acetyltransferase NGF-1 is required for blue light signal transduction in Neurospora crassa.
abstract: In Neurospora crassa and other filamentous fungi, light-dependent-specific phenomena are regulated by transcription factors WC-1 and WC-2. In addition to its transcriptional activity, WC-1 is able to directly sense light stimuli through a LOV sensor domain. Its location in the nucleus and heterodimerization with WC-2, together with the presence of a zinc-finger DNA-binding domain and an environmental sensor domain, all resemble the functional evolutionary architecture adopted by vertebrate nuclear receptors (NRs). Here we describe a scenario in which WC-1 represents a functional orthologue of NRs and acts through association with the chromatin-modifying coactivator NGF-1, which encodes a homologue of the yeast Gcn5p acetyltransferase. To support this view, we show a direct association between WC-1 and NGF-1 that depends on a WC-1 region containing a conserved functional LXXLL motif, a signature previously described as being an exclusive feature of NR/coactivator interaction. Our data suggest that a WC-1/NGF-1 complex is preassembled in the dark on light-inducible promoters and that, after exposure to light stimulation, NGF-1-associated HAT activity leads to histone H3 acetylation and transcriptional activation. Finally, we provide evidence for a NGF-1-independent acetylated form of WC-1. Overall our data indicate that Neurospora and higher eukaryotes share a common mechanism for the signal transduction of environmental stimuli.
authors.affiliation: Pasteur Cenci Bolognetti Foundation, Department of Biology and Biotechnology "Charles Darwin," Sapienza University of Rome, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Brenna
authors.forename: Benedetto
authors.initials: B
authors.lastname: Grimaldi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Filetici
authors.forename: Paola
authors.initials: P
authors.lastname: Ballario
mesh_terms: D000107:Acetylation; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D044127:Epigenesis, Genetic; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D051548:Histone Acetyltransferases / Q000737:chemistry / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D008027:Light; D008969:Molecular Sequence Data; D009492:Neurospora crassa / Q000201:enzymology / Q000378:metabolism* / Q000528:radiation effects; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011499:Protein Processing, Post-Translational; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000528:radiation effects; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D006657:Histones; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; C105589:wc-1 protein, Neurospora crassa; D051548:Histone Acetyltransferases