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Molecular and Pharmacological Characterization of the Interaction between Human Geranylgeranyltransferase Type I and

Sonja Hinz1,2, Dominik Jung1, Dorota Hauert1

  • 1Center for Biomedical Education and Research (ZBAF), Faculty of Health, Institute of Pharmacology and Toxicology, School of Medicine, University of Witten/Herdecke, 58453 Witten, Germany.

International Journal of Molecular Sciences
|April 3, 2021
PubMed

Insights

Researchers developed a NanoBiT assay to study geranylgeranyltransferase type-I (GGTase-I) and its substrate Rap1B. This assay helps investigate GGTase-I inhibitors for cancer therapy by analyzing Rap1B interactions.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cancer Research

Background:

  • Geranylgeranyltransferase type-I (GGTase-I) is crucial for tumor development and metastasis.
  • GGTase-I inhibitors are developed as anti-cancer drugs targeting protein function and membrane association.
  • Rap subfamilies, like Rap1B, are involved in cell differentiation and growth, making them key targets.

Purpose of the Study:

  • To develop a novel NanoBiT assay for monitoring the interaction between human GGTase-I and its substrate Rap1B.
  • To investigate the impact of Rap1B prenylation-deficient mutants on GGTase-I interaction.
  • To explore the role of adenosine receptors in modulating GGTase-I and Rap1B interaction.

Main Methods:

  • Development of a NanoBiT assay to quantify GGTase-I and Rap1B interactions.
  • Design and analysis of Rap1B prenylation-deficient mutants (C181G, C181S, ΔCQLL).
  • Investigation of the effect of adenosine receptor activation (A2AAR, A2BAR) on GGTase-I/Rap1B interaction.

Main Results:

  • The NanoBiT assay successfully monitored GGTase-I and Rap1B interactions.
  • Rap1B mutants C181G and C181S showed interaction with GGTase-I, while ΔCQLL exhibited reduced interaction due to CAAX motif deletion.
  • A CAAX inhibitor blocked Rap1B-GGTase-I interaction, and adenosine receptor activation enhanced it.

Conclusions:

  • The NanoBiT assay is a valuable tool for studying GGTase-I inhibitor pharmacology.
  • Adenosine receptors A2AAR and A2BAR activation modulate Rap1B prenylation and function.
  • A2AAR and A2BAR antagonists represent potential therapeutic strategies for Rap1B-overexpressing cancers.
Keywords:
Adenosine A2B- and A2A-receptorGGTI-298NanoBiT assayRap1Bgeranylgeranyltransferase type I

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