Up-regulation in late pregnancy of both Go1α and Go2α isoforms in human myometrium

doi:10.1016/0922-4106(94)90004-3

European Journal of Pharmacology: Molecular Pharmacology

Volume 288, Issue 1, 15 December 1994, Pages 9-15

https://doi.org/10.1016/0922-4106(94)90004-3 Get rights and content

Abstract

The nature of the 39 kDa pertussis toxin substrate previously detected in human pregnant myometrium was investigated. Comparison of membranes from non-pregnant and from 39–40 week pregnant myometrium revealed a higher level at 39 kDa of pertussis toxin ADP-ribosylation and G_oα immunoreactivity in late pregnancy. Furthermore, quantification of both G_oα isoforms with specific anti-α_o1- and α_o2-antibodies revealed an increase in their expression in late pregnancy. At the same time, only limited changes in the levels of G_i1,2, G_i3 and G_q were observed. In rat myometrial membranes, neither pertussis toxin substrate nor G_oα immunoreactivity could be detected at the 39 kDa level. These results demonstrate that, in the human myometrium in late pregnancy, there is an increase in the expression of both isoforms of the G_oα subunits, suggesting a role for these proteins throughout gestation and/or near term for parturition.

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Up-regulation in late pregnancy of both Go1α and Go2α isoforms in human myometrium

Abstract

J. Biol. Chem.

J. Biol. Chem.

FEBS Lett.

FEBS Lett.

J. Biol. Chem.

Neuron.

FEBS Lett.

Am. J. Gynecol.

Biochem. Biophys. Res. Commun.

FEBS Lett.

FEBS Lett.

Pregnancy suppresses G-protein coupling to phosphoinositide hydrolysis in guinea pig myometrium

Am. J. Physiol.

Highly sensitive immunoassay for the α-subunit of the GTP-binding protein Go and its regional distribution in bovine brain

J. Neurochem.

Go, a GTP-binding protein: immunochemical and immunohistochemical localization in the rat

J. Neurochem.

Ontogeny of the GTP-binding protein Go in rat brain and heart

J. Neurochem.

Up-regulation in late pregnancy of both G_o1α and G_o2α isoforms in human myometrium