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Updated: Oct 7, 2026

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
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Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay

Published on: May 3, 2018

Caveolin-1 and a 29-kDa caveolin-associated protein are phosphorylated on tyrosine in cells expressing a

C Corley Mastick1, A R Sanguinetti, J H Knesek

  • 1Department of Biochemistry, University of Nevada, Reno, Nevada 89557, USA. cmastick@med.unr.edu

Experimental Cell Research
|May 8, 2001
PubMed

Insights

Caveolin-1 phosphorylation by v-Abl kinase is observed, but it does not solely cause cell changes. This finding impacts understanding of oncogene-driven cell transformation and tyrosine kinase substrates.

Area of Science:

  • Cell Biology
  • Molecular Oncology
  • Biochemistry

Background:

  • Caveolin-1, a protein involved in cell signaling, was initially linked to oncogenic transformation via tyrosine phosphorylation.
  • Tyrosine kinases, such as v-Src, can phosphorylate caveolin-1, suggesting a role in cancer development.

Purpose of the Study:

  • To investigate the interaction and phosphorylation of caveolin-1 by the v-Abl tyrosine kinase.
  • To determine if caveolin-1 phosphorylation is sufficient to induce cellular changes associated with v-Abl transformation.

Main Methods:

  • Analysis of phosphotyrosine signals in v-Abl-transformed cells.
  • Biochemical assays to identify preferred kinase substrates.
  • Use of a temperature-sensitive v-Abl allele (ts120 v-Abl) to study functional consequences.

Main Results:

  • Caveolin-1 and a 29 kDa associated protein are highly phosphorylated on tyrosine in v-Abl-expressing cells.
  • v-Abl kinase preferentially phosphorylates caveolin-1 and the 29 kDa protein.
  • Phosphorylation of caveolin-1 at tyrosine 14 occurs but does not lead to loss of caveolin expression or cell adhesion.

Conclusions:

  • Caveolin-1 and the 29 kDa protein are likely direct substrates of the Abl kinase.
  • Caveolin-1 phosphorylation, while occurring in v-Abl-transformed cells, is not the sole mediator of v-Abl-induced cellular alterations like loss of adhesion.

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