Abstract
Human telomere length is controlled by a negative feedback loop based on the binding of TRF1 to double-stranded telomeric DNA. The TRF1 complex recruits POT1, a single-stranded telomeric DNA-binding protein necessary for cis-inhibition of telomerase. By mass spectrometry, we have identified a new telomeric protein, which we have named POT1-interacting protein 1 (PIP1). PIP1 bound both POT1 and the TRF1-interacting factor TIN2 and could tether POT1 to the TRF1 complex. Reduction of PIP1 or POT1 levels with shRNAs led to telomere elongation, indicating that PIP1 contributes to telomere length control through recruitment of POT1.
Copyright 2004 Cold Spring Harbor Laboratory Press ISSN
Publication types
-
Comparative Study
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Carrier Proteins / metabolism*
-
Cloning, Molecular
-
Fluorescent Antibody Technique
-
HeLa Cells
-
Humans
-
Intracellular Signaling Peptides and Proteins*
-
Mass Spectrometry
-
RNA Interference
-
Shelterin Complex
-
Telomere / metabolism
-
Telomere / physiology*
-
Telomere-Binding Proteins / metabolism*
-
Telomeric Repeat Binding Protein 1 / metabolism*
-
Two-Hybrid System Techniques
Substances
-
Carrier Proteins
-
Intracellular Signaling Peptides and Proteins
-
PAK1IP1 protein, human
-
POT1 protein, human
-
Shelterin Complex
-
TINF2 protein, human
-
Telomere-Binding Proteins
-
Telomeric Repeat Binding Protein 1