title: Regulation of Neurospora Catalase-3 by global heterochromatin formation and its proximal heterochromatin region.
abstract: Catalase-3 (CAT-3) constitutes the main catalase activity in growing hyphae of Neurospora crassa, and its activity increases during exponential growth or is induced under different stress conditions. Although extensive progress has been made to identify catalase regulators, the regulation mechanism of CAT-3 at the chromatin level still remains unclear. Here, we aim at investigating the molecular regulation mechanisms of cat-3 at the chromatin level. We found that CAT-3 protein levels increased in mutants defective in proper global heterochromatin formation. Bioinformatics analysis identified a 5-kb AT-rich sequence adjacent to the cat-3 promoter as a heterochromatin region because of its enrichment of H3K9me3 and HP1. Expression of CAT-3 was induced by H2O2treatment in wild-type and such change occurred along with the accumulation of histone H3 acetylation at 5-kb heterochromatin boundaries and cat-3 locus, but without alteration of its H3K9me3 repressive modification. Moreover, disruption of 5-kb heterochromatin region results in elevated cat-3 expression, and higher levels of cat-3 expression were promoted by the combination with global heterochromatin defective mutants. Interestingly, the molecular weight and activity bands of CAT-3 protein are different in heterochromatin defective mutants compared with those in wild-type, suggesting that its N-terminal processing and modification may be altered. Our study indicates that the local chromatin structure creates a heterochromatin repressive environment to repress nearby gene expression.
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Yajun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Zhaolan
authors.initials: Z
authors.lastname: Ding
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Kexin
authors.initials: K
authors.lastname: Gai
authors.affiliation: College of Life Science, Heilongjiang University, Harbin 150080, China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Han
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Farah Naz
authors.initials: FN
authors.lastname: Kaleri
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: He
authors.affiliation: State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China. Electronic address: wangying@cau.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
mesh_terms: D002374:Catalase / Q000235:genetics* / Q000378:metabolism; D042002:Chromatin Assembly and Disassembly / Q000187:drug effects; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D006570:Heterochromatin / Q000737:chemistry* / Q000378:metabolism; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D025301:Hyphae / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009492:Neurospora crassa / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011499:Protein Processing, Post-Translational
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D005656:Fungal Proteins; D006570:Heterochromatin; D006657:Histones; D000090266:Chromobox Protein Homolog 5; D006861:Hydrogen Peroxide; D002374:Catalase
keywords: Catalase-3; Heterochromatin; Hydrogen peroxide; Post-translational modification