Cellular and Molecular Life Sciences

, Volume 74, Issue 8, pp 1379–1390 | Cite as

Gaq proteins: molecular pharmacology and therapeutic potential

  • Danielle Kamato
  • Partha Mitra
  • Felicity Davis
  • Narin Osman
  • Rebecca Chaplin
  • Peter J. Cabot
  • Rizwana Afroz
  • Walter Thomas
  • Wenhua Zheng
  • Harveen Kaur
  • Margaret Brimble
  • Peter J. Little


Seven transmembrane G protein-coupled receptors (GPCRs) have gained much interest in recent years as it is the largest class among cell surface receptors. G proteins lie in the heart of GPCRs signalling and therefore can be therapeutically targeted to overcome complexities in GPCR responses and signalling. G proteins are classified into four families (Gi, Gs, G12/13 and Gq); Gq is further subdivided into four classes. Among them Gαq and Gαq/11 isoforms are most crucial and ubiquitously expressed; these isoforms are almost 88% similar at their amino acid sequence but may exhibit functional divergences. However, uncertainties often arise about Gαq and Gαq/11 inhibitors, these G proteins might also have suitability to the invention of novel-specific inhibitors for each isoforms. YM-254890 and UBO-QIC are discovered as potent inhibitors of Gαq functions and also investigated in thrombin protease-activated receptor (PAR)-1 inhibitors and platelet aggregation inhibition. The most likely G protein involved in PAR-1 stimulates responses is one of the Gαq family isoforms. In this review, we highlight the molecular structures and pharmacological responses of Gαq family which may reflect the biochemical and molecular role of Gαq and Gαq/11. The advanced understanding of Gαq and Gαq/11 role in GPCR signalling may shed light on our understanding on cell biology, cellular physiology and pathophysiology and also lead to the development of novel therapeutic agents for a number of diseases.


G proteins Isoforms G Protein-coupled receptors GPCRs PAR-1 Hyperelongation Atherosclerosis G alpha q 


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Copyright information

© Springer International Publishing 2016

Authors and Affiliations

  • Danielle Kamato
    • 1
  • Partha Mitra
    • 1
  • Felicity Davis
    • 1
  • Narin Osman
    • 1
    • 2
    • 3
  • Rebecca Chaplin
    • 1
  • Peter J. Cabot
    • 1
  • Rizwana Afroz
    • 4
  • Walter Thomas
    • 5
  • Wenhua Zheng
    • 6
  • Harveen Kaur
    • 7
  • Margaret Brimble
    • 7
  • Peter J. Little
    • 1
    • 2
    • 8
  1. 1.School of Pharmacy, Pharmacy Australia Centre of ExcellenceThe University of QueenslandWoolloongabbaAustralia
  2. 2.School of Medical SciencesRMIT UniversityBundooraAustralia
  3. 3.Department of ImmunologyMonash UniversityMelbounreAustralia
  4. 4.Department of BiochemistryPrimeasia UniversityBananiBangladesh
  5. 5.School of Biomedical SciencesThe University of QueenslandSt. LuciaAustralia
  6. 6.Faculty of Health SciencesUniversity of MacauTaipaChina
  7. 7.Department of Chemistry, School of Biological SciencesUniversity of AucklandAucklandNew Zealand
  8. 8.Xinhua College of Sun Yat-sen UniversityGuangzhouChina

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