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. 1990 Sep 15;270(3):765–769. doi: 10.1042/bj2700765

Concurrent up-regulation of guanine-nucleotide-binding proteins Gi1 alpha, Gi2 alpha and Gi3 alpha in adipocytes of hypothyroid rats.

G Milligan 1, E D Saggerson 1
PMCID: PMC1131798  PMID: 2122886

Abstract

Rat white adipocytes express three distinct 'Gi-like' guanine-nucleotide-binding proteins (G-proteins) [Mitchell, Griffiths, Saggerson, Houslay, Knowler & Milligan (1989) Biochem. J. 262, 403-408]. We have previously noted elevated levels of Gi in membranes of adipocytes from hypothyroid rats [Milligan, Spiegel, Unson & Saggerson (1987) Biochem. J. 247, 223-227]. Using a series of anti-peptide antisera able to discriminate between the individual gene products we have examined levels of each Gi-like G-protein in adipocyte membranes of hypothyroid rats compared with euthyroid controls. We demonstrate that up-regulation of Gi in adipocytes of hypothyroid rats is not restricted to a single subtype of Gi but that each of Gi1 alpha, Gi2 alpha and Gi3 alpha is present at markedly higher levels compared with euthyroid animals. In contrast, levels of both the 45 and 42 kDa forms of Gs alpha were not altered substantially in the hypothyroid state.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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