Role of linker histone in the formation and function of nucleolus.

2016 Fiscal Year Final Research Report

• Project/Area Number: 26850230
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Applied molecular and cellular biology
• Research Institution: The University of Tokyo
• Principal Investigator: Hayakawa Koji 東京大学, 大学院農学生命科学研究科(農学部), 特任助教 (50636800)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: リンカーヒストン / 核小体 / エピジェネティクス / クロマチン

Outline of Final Research Achievements

Linker histone H1 directly binds with DNA and thereby remodels and stabilizes the chromatin structure. Ten H1 variants in mammals are classified into somatic and germ cell-specific variants. H1T is one of the germ cell-specific H1s that is highly expressed in testis, but little more than this expression profile is known about H1T.
Here, we describe the target loci and function of H1T. To elucidate the intracellular localization and target loci of H1T, fluorescent immunostaining and ChIP-seq were performed. H1T accumulated in nucleoli and predominantly targeted ribosomal DNA (rDNA) repeats, which differs from somatic H1s’ targets. Furthermore, the function of H1T at rDNA repeats was analyzed. According to the results of DNase I sensitive assay and RT-qPCR, H1T repressed rDNA transcription by condensing the chromatin structure. Imaging analysis indicated that H1T expression affected nucleolar formation. Collectively, H1T plays a role in rDNA transcription by targeting rDNA repeats.

Free Research Field

エピジェネティクス