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Internuclear diffusion of histone H1 within cellular compartments of Aspergillus nidulans.

ABSTRACT: Histone H1 is an evolutionarily conserved linker histone protein that functions in arranging and stabilizing chromatin structure and is frequently fused to a fluorescent protein to track nuclei in live cells. In time-lapse analyses, we observed stochastic exchange of photoactivated Dendra2-histone H1 protein between nuclei within the same cellular compartment. We also observed exchange of histones between genetically distinct nuclei in a heterokaryon derived from fusion of strains carrying histone H1-RFP or H1-GFP. Subsequent analysis of the resulting uninucleate conidia containing both RFP- and GFP-labeled histone H1 proteins showed only parental genotypes, ruling out genetic recombination and diploidization. These data together suggest that the linker histone H1 protein can diffuse between non-daughter nuclei in the filamentous fungus Aspergillus nidulans.

SUBMITTER: Mela AP

PROVIDER: S-EPMC6095493 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Internuclear diffusion of histone H1 within cellular compartments of Aspergillus nidulans.

Mela Alexander P AP Momany Michelle M

PloS one 20180816 8

Histone H1 is an evolutionarily conserved linker histone protein that functions in arranging and stabilizing chromatin structure and is frequently fused to a fluorescent protein to track nuclei in live cells. In time-lapse analyses, we observed stochastic exchange of photoactivated Dendra2-histone H1 protein between nuclei within the same cellular compartment. We also observed exchange of histones between genetically distinct nuclei in a heterokaryon derived from fusion of strains carrying histo ...[more]

PMID: 30114268

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