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Updated: Apr 8, 2026

Identification of Kinase-substrate Pairs Using High Throughput Screening
11:13

Identification of Kinase-substrate Pairs Using High Throughput Screening

Published on: August 29, 2015

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A Screen for Extracellular Signal-Regulated Kinase-Primed Glycogen Synthase Kinase 3 Substrates Identifies the p53

Crystal Woodard1, Gangling Liao2, C Rory Goodwin3

  • 1High Throughput Biology Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA Department of Pharmacology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.

Journal of Virology
|June 26, 2015
PubMed
Abstract

Insights

Kaposi's sarcoma-associated herpesvirus (KSHV) infection promotes cancer by altering cell signaling. Inhibiting the iASPP protein in KSHV-infected cells induces cancer cell death, offering a new therapeutic strategy.

Area of Science:

  • Oncology
  • Virology
  • Molecular Biology

Background:

  • Kaposi's sarcoma-associated herpesvirus (KSHV) drives malignancies like primary effusion lymphoma (PEL).
  • The KSHV LANA protein promotes cancer cell growth and survival by modulating cellular kinases, including ERK and GSK-3.
  • Understanding LANA's kinase interactions is crucial for developing targeted therapies against KSHV-driven cancers.

Purpose of the Study:

  • To identify cellular proteins phosphorylated by ERK and GSK-3 in the context of KSHV infection.
  • To investigate the role of identified substrates, specifically iASPP, in PEL cell survival and apoptosis.
  • To evaluate iASPP inhibition as a potential therapeutic strategy for KSHV-associated malignancies.

Main Methods:

  • Protein microarray screening to identify ERK-primed GSK-3 substrates.
  • Mass spectrometry and cotransfection assays to validate iASPP as a substrate and assess its degradation.
  • Treatment of PEL cells with an iASPP inhibitor, alone and in combination with Nutlin-3, to assess apoptosis induction.

Main Results:

  • Identified 58 potential ERK-primed GSK-3 substrates, with iASPP confirmed as a target.
  • GSK-3 mediates the degradation of iASPP, which normally inhibits p53-induced apoptosis.
  • Inhibition of iASPP induced apoptosis in KSHV-infected PEL cells, an effect additive with Nutlin-3.

Conclusions:

  • iASPP is a key mediator of KSHV-driven cell survival by antagonizing apoptosis.
  • Targeting iASPP represents a promising therapeutic approach to sensitize KSHV-positive PEL cells to cell death.
  • This study reveals a novel mechanism by which KSHV promotes oncogenesis and identifies a potential vulnerability.

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