Calcium ions function as a booster of chromosome condensation

Rinyaporn Phengchat; Hideaki Takata; Kenichi Morii; Noriko Inada; Hideji Murakoshi; Susumu Uchiyama; Kiichi Fukui

doi:10.1038/srep38281

Calcium ions function as a booster of chromosome condensation

Sci Rep. 2016 Dec 2:6:38281. doi: 10.1038/srep38281.

Authors

Rinyaporn Phengchat¹, Hideaki Takata¹, Kenichi Morii¹, Noriko Inada², Hideji Murakoshi³, Susumu Uchiyama¹, Kiichi Fukui¹

Affiliations

¹ Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan.
² The Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama-Cho Ikoma-shi, Nara 630-0192, Japan.
³ Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan.

Abstract

Chromosome condensation is essential for the faithful transmission of genetic information to daughter cells during cell division. The depletion of chromosome scaffold proteins does not prevent chromosome condensation despite structural defects. This suggests that other factors contribute to condensation. Here we investigated the contribution of divalent cations, particularly Ca²⁺, to chromosome condensation in vitro and in vivo. Ca²⁺ depletion caused defects in proper mitotic progression, particularly in chromosome condensation after the breakdown of the nuclear envelope. Fluorescence lifetime imaging microscopy-Förster resonance energy transfer and electron microscopy demonstrated that chromosome condensation is influenced by Ca²⁺. Chromosomes had compact globular structures when exposed to Ca²⁺ and expanded fibrous structures without Ca²⁺. Therefore, we have clearly demonstrated a role for Ca²⁺ in the compaction of chromatin fibres.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Calcium / metabolism
Calcium / pharmacology*
Calcium Chelating Agents / metabolism
Calcium Chelating Agents / pharmacology
Chromatin / drug effects*
Chromatin / metabolism
Chromatin / ultrastructure
Chromatin Assembly and Disassembly / drug effects*
DNA Packaging / drug effects*
Egtazic Acid / analogs & derivatives
Egtazic Acid / metabolism
Egtazic Acid / pharmacology
Fluorescence Resonance Energy Transfer
Fluorescent Dyes / chemistry
Fura-2 / analogs & derivatives
Fura-2 / chemistry
Gene Expression
Genes, Reporter
Green Fluorescent Proteins / genetics
Green Fluorescent Proteins / metabolism
HeLa Cells
Humans
Luminescent Proteins / genetics
Luminescent Proteins / metabolism
Metaphase / drug effects*
Microscopy, Fluorescence
Nuclear Envelope / drug effects
Nuclear Envelope / metabolism
Nuclear Envelope / ultrastructure
Red Fluorescent Protein

Substances

Calcium Chelating Agents
Chromatin
Fluorescent Dyes
Luminescent Proteins
enhanced green fluorescent protein
fura-2-am
Green Fluorescent Proteins
Egtazic Acid
1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid
Calcium
Fura-2