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The IAP proteins: caspase inhibitors and beyond

B W Richter1, C S Duckett

  • 1Division of Clinical Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.

Science'S STKE : Signal Transduction Knowledge Environment
|December 26, 2001
PubMed

Insights

Inhibitors of apoptosis proteins (IAPs) are crucial regulators that prevent cell death. This review explores their diverse roles beyond apoptosis, including signal transduction and protein ubiquitination, highlighting ongoing research into their functions.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Apoptosis, or programmed cell death, is a vital biological process for maintaining organismal health and homeostasis.
  • Dysregulation of apoptosis can lead to detrimental conditions, necessitating tight control by regulatory proteins.
  • Inhibitors of apoptosis proteins (IAPs) are key regulators that prevent uncontrolled cell death.

Purpose of the Study:

  • To review the recently discovered and characterized inhibitors of apoptosis proteins (IAPs).
  • To explore the multifaceted roles of IAPs beyond their canonical function in inhibiting apoptosis.
  • To highlight emerging evidence on IAP involvement in signal transduction, cell cycle regulation, and protein ubiquitination.

Main Methods:

  • Literature review of recent discoveries and characterizations of IAPs.
  • Analysis of evidence for IAP functions in viral infections and cellular processes.
  • Synthesis of current understanding regarding IAP interactions and regulatory mechanisms.

Main Results:

  • IAPs were initially identified in viruses as a mechanism to subvert host cell apoptosis.
  • Evidence suggests IAPs play roles in signal transduction pathways and cell cycle regulation.
  • Recent findings indicate IAPs are involved in protein ubiquitination processes.

Conclusions:

  • IAPs possess diverse functions extending beyond apoptosis inhibition.
  • The breadth of IAP functions and their binding partners are areas of active investigation.
  • Further research is needed to fully elucidate the complex roles of IAPs in cellular regulation.

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