title: POT1-interacting protein PIP1: a telomere length regulator that recruits POT1 to the TIN2/TRF1 complex.
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.
authors.affiliation: Laboratory for Cell Biology and Genetics and Laboratory for Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York 10021, USA. jeffery.ye@med.nyu.edu
authors.forename: Jeffrey Zheng-Sheng
authors.initials: JZ
authors.lastname: Ye
authors.forename: Dirk
authors.initials: D
authors.lastname: Hockemeyer
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Krutchinsky
authors.forename: Diego
authors.initials: D
authors.lastname: Loayza
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Hooper
authors.forename: Brian T
authors.initials: BT
authors.lastname: Chait
authors.forename: Titia
authors.initials: T
authors.lastname: de Lange
mesh_terms: D002352:Carrier Proteins / Q000378:metabolism*; D003001:Cloning, Molecular; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D013058:Mass Spectrometry; D034622:RNA Interference; D000089804:Shelterin Complex; D016615:Telomere / Q000378:metabolism / Q000502:physiology*; D034501:Telomere-Binding Proteins / Q000378:metabolism*; D035321:Telomeric Repeat Binding Protein 1 / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; C430457:PAK1IP1 protein, human; C440849:POT1 protein, human; D000089804:Shelterin Complex; C440868:TINF2 protein, human; D034501:Telomere-Binding Proteins; D035321:Telomeric Repeat Binding Protein 1