Molecular dissection of PINCH-1 reveals a mechanism of coupling and uncoupling of cell shape modulation and survival

J Biol Chem. 2005 Jul 29;280(30):27631-7. doi: 10.1074/jbc.M504189200. Epub 2005 Jun 7.

Abstract

How cells couple and uncouple regulation of cellular processes such as shape change and survival is an important question in molecular cell biology. PINCH-1, a widely expressed protein consisting of five LIM domains and a C-terminal tail, is an essential focal adhesion protein with multiple functions including regulation of the integrin-linked kinase (ILK) level, cell shape, and survival signaling. We show here that the LIM1-mediated interaction with ILK regulates all these three processes. By contrast, the LIM4-mediated interaction with Nck-2, which regulates cell morphology and migration, is not required for the control of the ILK level and survival. Remarkably, a short 15-residue tail C-terminal to LIM5 is required for both cell shape modulation and survival, albeit it is not required for the control of the ILK level. The C-terminal tail not only regulates PINCH-1 localization to focal adhesions but also functions after it localizes there. These findings suggest that PINCH-1 functions as a molecular platform for coupling and uncoupling diverse cellular processes via overlapping but yet distinct domain interactions.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Amino Acid Sequence
  • Apoptosis
  • Blotting, Western
  • Cell Adhesion
  • Cell Shape
  • Cell Survival
  • DNA / metabolism
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / physiology*
  • Green Fluorescent Proteins / metabolism
  • HeLa Cells
  • Humans
  • LIM Domain Proteins
  • Membrane Proteins
  • Molecular Sequence Data
  • Oncogene Proteins / metabolism
  • Phosphorylation
  • Point Mutation
  • Protein Binding
  • Protein Structure, Tertiary
  • RNA, Small Interfering / metabolism
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Transfection

Substances

  • Adaptor Proteins, Signal Transducing
  • DNA-Binding Proteins
  • LIM Domain Proteins
  • LIMS1 protein, human
  • Membrane Proteins
  • NCK2 protein, human
  • Oncogene Proteins
  • RNA, Small Interfering
  • Green Fluorescent Proteins
  • DNA