Abstract
Inactivation of the von Hippel-Lindau (VHL) tumor suppressor is associated with renal carcinoma, hemangioblastoma and pheochromocytoma. The VHL protein is a component of a ubiquitin ligase complex that ubiquitinates and degrades hypoxia inducible factor-α (HIF-α). Degradation of HIF-α by VHL is proposed to suppress tumorigenesis and tumor angiogenesis. Several lines of evidence also suggest important roles for HIF-independent VHL functions in tumor suppression and other biological processes. Using GST-VHL pull-down experiment and mass spectrometry, we detected an interaction between VHL and heterochromatin protein 1 (HP1). We identified a conserved HP1-binding motif (PXVXL) in the β domain of VHL, which is disrupted in a renal carcinoma-associated P81S mutant. We show that the VHL P81S mutant displays reduced binding to HP1, yet retains the ability to interact with elongin B, elongin C, and cullin 2 and is fully capable of degrading HIF-α. We also demonstrate that HP1 increases the chromatin association of VHL. These results suggest a role for the VHL-HP1 interaction in VHL chromatin targeting.
Copyright © 2011 Elsevier Inc. All rights reserved.
Publication types
-
Research Support, N.I.H., Extramural
MeSH terms
-
Amino Acid Motifs
-
Amino Acid Substitution
-
Animals
-
Cell Line
-
Chromatin / genetics
-
Chromatin / metabolism*
-
Chromobox Protein Homolog 5
-
Chromosomal Proteins, Non-Histone / genetics
-
Chromosomal Proteins, Non-Histone / metabolism*
-
Cullin Proteins / genetics
-
Cullin Proteins / metabolism
-
Elongin
-
Humans
-
Hypoxia-Inducible Factor 1, alpha Subunit / genetics
-
Hypoxia-Inducible Factor 1, alpha Subunit / metabolism*
-
Kidney Neoplasms / genetics
-
Kidney Neoplasms / metabolism*
-
Mice
-
Mutation, Missense
-
Neovascularization, Pathologic / genetics
-
Neovascularization, Pathologic / metabolism
-
Proteolysis*
-
Transcription Factors / genetics
-
Transcription Factors / metabolism
-
Ubiquitination / genetics
-
Von Hippel-Lindau Tumor Suppressor Protein / genetics
-
Von Hippel-Lindau Tumor Suppressor Protein / metabolism*
Substances
-
CUL2 protein, human
-
Chromatin
-
Chromosomal Proteins, Non-Histone
-
Cullin Proteins
-
ELOB protein, human
-
ELOC protein, human
-
Elob protein, mouse
-
Eloc protein, mouse
-
Elongin
-
HIF1A protein, human
-
Hypoxia-Inducible Factor 1, alpha Subunit
-
Transcription Factors
-
Chromobox Protein Homolog 5
-
Von Hippel-Lindau Tumor Suppressor Protein
-
VHL protein, human