G proteins, or guanine nucleotide-binding proteins, regulate cell signaling by switching between 'on' and 'off' states through GTP hydrolysis. They are crucial for transmitting signals from external stimuli to the cell interior, impacting various cellular functions and systemic processes.
In 1980, Alfred G. Gilman and Martin Rodbell discovered G proteins while studying the effects of adrenaline on cell stimulation. They observed that adrenaline binding to receptors did not directly activate enzymes within the cell.
In 1987, studies on muscarinic regulation of the atrial G-protein regulated inwardly rectifying K+ (GIRK) channel demonstrated a direct function of the β/γ complex. This finding highlighted the role of the β/γ complex beyond being a mere binding partner for Gα-subunits.
In 1989, Landis and colleagues discovered that mutations inhibiting GTPase activity activate the alpha chain of Gs protein, leading to the stimulation of adenylyl cyclase in human pituitary tumors.
In 1990, Gqα and G11α were identified and characterized as 42 kDa polypeptides that fulfilled the criteria for phosphoinositidase Cβ-linked G-proteins. These proteins were shown to be widely expressed and play a role in elevating intracellular calcium levels.
The 1992 Nobel Prize in Physiology or Medicine was awarded to Edwin G. Krebs and Edmond H. Fischer for their discovery of how reversible phosphorylation acts as a switch to activate proteins and regulate cellular processes like glycogenolysis.
Samama and colleagues in 1993 discovered a mutation-induced activated state of the beta 2-adrenergic receptor, expanding the understanding of the ternary complex model.
The 1994 Nobel Prize in Physiology or Medicine was given to Alfred G. Gilman and Martin Rodbell for their research on G-proteins and their role in cell signal transduction.
The crystal structure of a G-protein beta gamma dimer was revealed at 2.1A resolution in 1996 by Sondek J and colleagues.
Ric-8 is a novel conserved protein that is required for G(q)alpha signaling in the C. elegans nervous system.
The 2000 Nobel Prize in Physiology or Medicine was presented to Eric Kandel, Arvid Carlsson, and Paul Greengard for their studies on neurotransmitters like dopamine that act through GPCRs.
In 2003, Azzi M and team found that beta-arrestin mediates the activation of MAPK by inverse agonists, revealing distinct active conformations for G protein-coupled receptors.
The 2004 Nobel Prize in Physiology or Medicine was granted to Richard Axel and Linda B. Buck for their work on G protein-coupled olfactory receptors.
In 2005, Spiegelberg BD and Hamm HE discovered that G betagamma binds histone deacetylase 5 (HDAC5) and inhibits its transcriptional co-repression activity.
In the 1970s, the existence of heterotrimeric guanine nucleotide-binding proteins (G-proteins) that transduce signals from G-protein-coupled receptors to effector systems was suggested. Through bacterial toxins and mutant cell lines, these proteins were identified and purified, leading to a better understanding of their molecular structure and function.
In 2008, Scheerer and colleagues published a study in the journal Nature, presenting the crystal structure of opsin in its G-protein-interacting conformation.
In 2009, a study provided structural evidence supporting a sequential release mechanism for the activation of heterotrimeric G proteins.
In 2011, Rasmussen and colleagues revealed the crystal structure of the beta2 adrenergic receptor-Gs protein complex, providing insights into the molecular interactions between the receptor and the protein.
The 2012 Nobel Prize in Chemistry was given to Brian Kobilka and Robert Lefkowitz for their research on the function of GPCRs.
In 2018, small molecules that target heterotrimeric G proteins were discussed in the article 'Eur J Pharmacol'.
Bhatnagar N and Pandey in 2020 found that interactions of heterotrimeric G-Proteins are conserved even with the loss of regulatory elements in some plants.