Disruption of human vigilin impairs chromosome condensation and segregation.

Abstract

Appropriate packaging and condensation are critical for eukaryotic chromatin's accommodation and separation during cell division. Human vigilin, a multi-KH-domain nucleic acid-binding protein, is associated with alpha satellites of centromeres. DDP1, a vigilin's homolog, is implicated with chromatin condensation and segregation. The expression of vigilin was previously reported to elevate in highly proliferating tissues and increased in a subset of hepatocellular carcinoma patients. Other studies showed that vigilin interacts with CTCF, contributes to regulation of imprinted genes Igf2/H19, and colocalizes with HP1α on heterochromatic satellite 2 and β-satellite repeats. These studies indicate that human vigilin might be involved in chromatin remodeling and regular cell growth. To investigate the potential role of human vigilin in cell cycle, the correlations between vigilin and chromosomal condensation and segregation were studied. Depletion of human vigilin by RNA interference in HepG2 cells resulted in chromosome undercondensation and various chromosomal defects during mitotic phase, including chromosome misalignments, lagging chromosomes, and chromosome bridges. Aberrant polyploid nucleus in telophase was also observed. Unlike the abnormal staining pattern of chromosomes, the shape of spindle was normal. Furthermore, the chromatin showed a greater sensitivity to MNase digestion. Collectively, our findings show that human vigilin apparently participates in chromatin condensation and segregation.

• Authors: Ling Wei, Xiaoyan Xie, Junhong Li, Ran Li, Wenyan Shen, Shuwang Duan, Rongce Zhao, Wenli Yang, Qiuying Liu, Qiang Fu, Yang Qin
• Journal: Cell biology international (Cell Biol Int) Vol. 39 Issue 11 Pg. 1234-41 (Nov 2015) ISSN: 1095-8355 [Electronic] England
• PMID: 26032007 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 International Federation for Cell Biology.

Chemical References

• CBX5 protein, human
• Chromatin
• RNA-Binding Proteins
• Chromobox Protein Homolog 5
• high density lipoprotein binding protein

Topics

• Carcinoma, Hepatocellular (genetics, metabolism)
• Cell Cycle (genetics)
• Centromere (metabolism)
• Chromatin (drug effects, metabolism)
• Chromobox Protein Homolog 5
• Chromosome Segregation (physiology)
• Chromosomes, Human (genetics, physiology)
• Hep G2 Cells
• Humans
• Liver Neoplasms (genetics, metabolism)
• Mitosis (physiology)
• RNA Interference
• RNA-Binding Proteins (antagonists & inhibitors, genetics, metabolism)