Differential expression of protein kinase A, AKAP79, and PP2B in pregnant human myometrial membranes prior to and during labor

Chun Ying Ku, R. Ann Word, Barbara M. Sanborn

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

OBJECTIVE: We have previously shown that the association of protein kinase A (PKA) with purified myometrial plasma membrane declined at the end of pregnancy in the rat. This study was designed to determine if a similar decline in PKA occurred in pregnant human myometrium. METHODS: Myometrial plasma membranes were isolated from lower uterine segment tissues from not-in-labor (NIL) and in-labor (IL) patients undergoing cesarean delivery. Membrane proteins were subjected to Western blot analysis to detect PKA-catalytic (PKA-cat) and PKA-regulatory (PKA-reg) subunits, the PKA binding protein A-kinase anchoring protein 79 (AKAP79), protein phosphatase 2B (PP2B), and Gαq, a guanosine triphosphate (GTP)-binding protein. Protein levels were expressed relative to caveolin-1, which was invariant between the two groups. RESULTS: The amount of PKA-cat, PKA-reg, AKAP79, and PP2B in plasma membranes from myometrium of women in early labor decreased significantly compared with that in tissues from women not in labor. In contrast, Gαq did not change. All proteins were localized to myometrial smooth muscle cells by immunohistochemistry. CONCLUSIONS: Expression of PKA, PP2B, and AKAP79 is consistent with the presence of a functional AKAP-mediated signaling complex in pregnant human myometrial membranes. A small but significant decrease in PKA, AKAP79, and PP2B in myometrial tissues from women in labor may contribute to a decrease in negative feedback on and enhancement of contractant signals at term.

Original languageEnglish (US)
Pages (from-to)421-427
Number of pages7
JournalJournal of the Society for Gynecologic Investigation
Volume12
Issue number6
DOIs
StatePublished - Sep 2005

Fingerprint

Calcineurin
Cyclic AMP-Dependent Protein Kinases
Protein Kinases
Membranes
Myometrium
Cell Membrane
Staphylococcal Protein A
Carrier Proteins
Cats
Caveolin 1
Proteins
Guanosine Triphosphate
Smooth Muscle Myocytes
Membrane Proteins
Western Blotting
Immunohistochemistry
Pregnancy

Keywords

  • AKAP79
  • Human myometrium
  • Protein kinase A
  • Protein phosphatase (PP2B)

ASJC Scopus subject areas

  • Obstetrics and Gynecology

Cite this

Differential expression of protein kinase A, AKAP79, and PP2B in pregnant human myometrial membranes prior to and during labor. / Ku, Chun Ying; Word, R. Ann; Sanborn, Barbara M.

In: Journal of the Society for Gynecologic Investigation, Vol. 12, No. 6, 09.2005, p. 421-427.

Research output: Contribution to journalArticle

@article{defb6628f54e41c9be75e0ae982745db,
title = "Differential expression of protein kinase A, AKAP79, and PP2B in pregnant human myometrial membranes prior to and during labor",
abstract = "OBJECTIVE: We have previously shown that the association of protein kinase A (PKA) with purified myometrial plasma membrane declined at the end of pregnancy in the rat. This study was designed to determine if a similar decline in PKA occurred in pregnant human myometrium. METHODS: Myometrial plasma membranes were isolated from lower uterine segment tissues from not-in-labor (NIL) and in-labor (IL) patients undergoing cesarean delivery. Membrane proteins were subjected to Western blot analysis to detect PKA-catalytic (PKA-cat) and PKA-regulatory (PKA-reg) subunits, the PKA binding protein A-kinase anchoring protein 79 (AKAP79), protein phosphatase 2B (PP2B), and Gαq, a guanosine triphosphate (GTP)-binding protein. Protein levels were expressed relative to caveolin-1, which was invariant between the two groups. RESULTS: The amount of PKA-cat, PKA-reg, AKAP79, and PP2B in plasma membranes from myometrium of women in early labor decreased significantly compared with that in tissues from women not in labor. In contrast, Gαq did not change. All proteins were localized to myometrial smooth muscle cells by immunohistochemistry. CONCLUSIONS: Expression of PKA, PP2B, and AKAP79 is consistent with the presence of a functional AKAP-mediated signaling complex in pregnant human myometrial membranes. A small but significant decrease in PKA, AKAP79, and PP2B in myometrial tissues from women in labor may contribute to a decrease in negative feedback on and enhancement of contractant signals at term.",
keywords = "AKAP79, Human myometrium, Protein kinase A, Protein phosphatase (PP2B)",
author = "Ku, {Chun Ying} and Word, {R. Ann} and Sanborn, {Barbara M.}",
year = "2005",
month = "9",
doi = "10.1016/j.jsgi.2005.04.002",
language = "English (US)",
volume = "12",
pages = "421--427",
journal = "Reproductive Sciences",
issn = "1933-7191",
publisher = "SAGE Publications Inc.",
number = "6",

}

TY - JOUR

T1 - Differential expression of protein kinase A, AKAP79, and PP2B in pregnant human myometrial membranes prior to and during labor

AU - Ku, Chun Ying

AU - Word, R. Ann

AU - Sanborn, Barbara M.

PY - 2005/9

Y1 - 2005/9

N2 - OBJECTIVE: We have previously shown that the association of protein kinase A (PKA) with purified myometrial plasma membrane declined at the end of pregnancy in the rat. This study was designed to determine if a similar decline in PKA occurred in pregnant human myometrium. METHODS: Myometrial plasma membranes were isolated from lower uterine segment tissues from not-in-labor (NIL) and in-labor (IL) patients undergoing cesarean delivery. Membrane proteins were subjected to Western blot analysis to detect PKA-catalytic (PKA-cat) and PKA-regulatory (PKA-reg) subunits, the PKA binding protein A-kinase anchoring protein 79 (AKAP79), protein phosphatase 2B (PP2B), and Gαq, a guanosine triphosphate (GTP)-binding protein. Protein levels were expressed relative to caveolin-1, which was invariant between the two groups. RESULTS: The amount of PKA-cat, PKA-reg, AKAP79, and PP2B in plasma membranes from myometrium of women in early labor decreased significantly compared with that in tissues from women not in labor. In contrast, Gαq did not change. All proteins were localized to myometrial smooth muscle cells by immunohistochemistry. CONCLUSIONS: Expression of PKA, PP2B, and AKAP79 is consistent with the presence of a functional AKAP-mediated signaling complex in pregnant human myometrial membranes. A small but significant decrease in PKA, AKAP79, and PP2B in myometrial tissues from women in labor may contribute to a decrease in negative feedback on and enhancement of contractant signals at term.

AB - OBJECTIVE: We have previously shown that the association of protein kinase A (PKA) with purified myometrial plasma membrane declined at the end of pregnancy in the rat. This study was designed to determine if a similar decline in PKA occurred in pregnant human myometrium. METHODS: Myometrial plasma membranes were isolated from lower uterine segment tissues from not-in-labor (NIL) and in-labor (IL) patients undergoing cesarean delivery. Membrane proteins were subjected to Western blot analysis to detect PKA-catalytic (PKA-cat) and PKA-regulatory (PKA-reg) subunits, the PKA binding protein A-kinase anchoring protein 79 (AKAP79), protein phosphatase 2B (PP2B), and Gαq, a guanosine triphosphate (GTP)-binding protein. Protein levels were expressed relative to caveolin-1, which was invariant between the two groups. RESULTS: The amount of PKA-cat, PKA-reg, AKAP79, and PP2B in plasma membranes from myometrium of women in early labor decreased significantly compared with that in tissues from women not in labor. In contrast, Gαq did not change. All proteins were localized to myometrial smooth muscle cells by immunohistochemistry. CONCLUSIONS: Expression of PKA, PP2B, and AKAP79 is consistent with the presence of a functional AKAP-mediated signaling complex in pregnant human myometrial membranes. A small but significant decrease in PKA, AKAP79, and PP2B in myometrial tissues from women in labor may contribute to a decrease in negative feedback on and enhancement of contractant signals at term.

KW - AKAP79

KW - Human myometrium

KW - Protein kinase A

KW - Protein phosphatase (PP2B)

UR - http://www.scopus.com/inward/record.url?scp=24144461354&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=24144461354&partnerID=8YFLogxK

U2 - 10.1016/j.jsgi.2005.04.002

DO - 10.1016/j.jsgi.2005.04.002

M3 - Article

C2 - 15914039

AN - SCOPUS:24144461354

VL - 12

SP - 421

EP - 427

JO - Reproductive Sciences

JF - Reproductive Sciences

SN - 1933-7191

IS - 6

ER -