Heterochromatin protein 1alpha: a hallmark of cell proliferation relevant to clinical oncology.

ABSTRACT: Mammalian cells contain three closely related heterochromatin protein 1 (HP1) isoforms, HP1alpha, beta and gamma, which, by analogy to their unique counterpart in Schizosaccharomyces pombe, have been implicated in gene silencing, genome stability and chromosome segregation. However, the individual importance of each isoform during normal cell cycle and disease has remained an unresolved issue. Here, we reveal that HP1alpha shows a proliferation-dependent regulation, which neither HP1beta nor gamma display. During transient cell cycle exit, the HP1alpha mRNA and protein levels diminish. Transient depletion of HP1alpha, but not HP1beta or gamma, in tumoural and primary human cells leads to defects in chromosome segregation. Notably, analysis of an annotated collection of samples derived from

SUBMITTER: De Koning L 

PROVIDER: S-EPMC3378125 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature