G-proteins: implications for pathophysiology and disease.
This article focuses on the involvement of G-proteins in neuroendocrine secretion, cell growth and phenotype alterations. The current concept of hormonal activation of the GTPase cycle, as well as the molecular diversity of G-proteins families and receptor*G-protein*effector coupling, are described. Also described are certain G-proteins as possible proto-oncogenes and how point mutations and frame shift mutations alter G-protein function and determine the characteristics of various endocrine diseases. The article outlines in detail how receptors and G-proteins interact in prolactin and growth-hormone-secreting pituicytes, how G-proteins are involved in the growth and differentiation of preadipocytes and osteoblasts. All in all, it seems that hormonal activation through G-proteins is modulated through direct intra- and inter-signalling system cross-talk at the plasma membrane level (short-term) and through interactions on the level of transcription (HREs) from tyrosine kinases, steroid-like hormones and metabolic pathways. Pharmacological intervention to treat diseases where G-proteins are involved should take both long and short-term regulatory phenomena into consideration.
Gordeladze
J O
JO
Institute of Medical Biochemistry, University of Oslo, Blindern, Norway.
Johansen
P W
PW
Paulssen
R H
RH
Paulssen
E J
EJ
Gautvik
K M
KM
D000818:Animals; D004700:Endocrine System Diseases / Q000503:physiopathology; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D006801:Humans; D009154:Mutation; D011956:Receptors, Cell Surface / Q000378:metabolism; D015398:Signal Transduction
D011956:Receptors, Cell Surface; D019204:GTP-Binding Proteins