Normal hematopoiesis and inflammatory responses despite discrete signaling defects in Gα15 knockout mice

I. Davignon, M. D. Catalina, D. Smith, J. Montgomery, J. Swantek, J. Croy, M. Siegelman, T. M. Wilkie

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

Gα15 activates phospholipase Cβ in response to the greatest variety of agonist-stimulated heptahelical receptors among the four Gq class G-protein α subunits expressed in mammals. Gα15 is primarily expressed in hematopoietic cells in fetal and adult mice. We disrupted the Gα15 gene by homologous recombination in embryonic stem cells to identify its biological functions. Surprisingly, hematopoiesis was normal in Gα15(-/-) mice, Gα15(- /-) Gαq(-/-) double-knockout mice (which express only Gα11 in most hematopoietic cells), and Gα11(-/-) mice, suggesting functional redundancy in Gq class signaling. Inflammatory challenges, including thioglycolate- induced peritonitis and infection with Trichinella spiralis, stimulated similar responses in Gα15(-/-) adults and wild-type siblings. Agonist- stimulated Ca2+ release from intracellular stores was assayed to identify signaling defects in primary cultures of thioglycolate-elicited macrophages isolated from Gα15(-/-) mice. C5a-stimulated phosphoinositide accumulation and Ca2+ release was significantly reduced in Gα15(-/-) macrophages. Ca2+ signaling was abolished only in mutant cells pretreated with pertussis toxin, suggesting that the C5a receptor couples to both Gα15 and Gαi in vivo. Signaling evoked by other receptors coupled by Gq class α subunits appeared normal in Gα15(-/-) macrophages. Despite discrete signaling defects, compensation by coexpressed Gq and/or Gi class α subunits may suppress abnormalities in Gα15-deficient mice.

Original languageEnglish (US)
Pages (from-to)797-804
Number of pages8
JournalMolecular and Cellular Biology
Volume20
Issue number3
DOIs
StatePublished - Feb 2000

Fingerprint

Hematopoiesis
Knockout Mice
Thioglycolates
Macrophages
Gq-G11 GTP-Binding Protein alpha Subunits
Anaphylatoxin C5a Receptor
Trichinella spiralis
Homologous Recombination
Pertussis Toxin
Protein Subunits
Type C Phospholipases
Embryonic Stem Cells
Phosphatidylinositols
Peritonitis
Mammals
Infection
Genes

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cell Biology

Cite this

Normal hematopoiesis and inflammatory responses despite discrete signaling defects in Gα15 knockout mice. / Davignon, I.; Catalina, M. D.; Smith, D.; Montgomery, J.; Swantek, J.; Croy, J.; Siegelman, M.; Wilkie, T. M.

In: Molecular and Cellular Biology, Vol. 20, No. 3, 02.2000, p. 797-804.

Research output: Contribution to journalArticle

Davignon, I. ; Catalina, M. D. ; Smith, D. ; Montgomery, J. ; Swantek, J. ; Croy, J. ; Siegelman, M. ; Wilkie, T. M. / Normal hematopoiesis and inflammatory responses despite discrete signaling defects in Gα15 knockout mice. In: Molecular and Cellular Biology. 2000 ; Vol. 20, No. 3. pp. 797-804.
@article{b84692dba4694fde843dbc16551c11a2,
title = "Normal hematopoiesis and inflammatory responses despite discrete signaling defects in Gα15 knockout mice",
abstract = "Gα15 activates phospholipase Cβ in response to the greatest variety of agonist-stimulated heptahelical receptors among the four Gq class G-protein α subunits expressed in mammals. Gα15 is primarily expressed in hematopoietic cells in fetal and adult mice. We disrupted the Gα15 gene by homologous recombination in embryonic stem cells to identify its biological functions. Surprisingly, hematopoiesis was normal in Gα15(-/-) mice, Gα15(- /-) Gαq(-/-) double-knockout mice (which express only Gα11 in most hematopoietic cells), and Gα11(-/-) mice, suggesting functional redundancy in Gq class signaling. Inflammatory challenges, including thioglycolate- induced peritonitis and infection with Trichinella spiralis, stimulated similar responses in Gα15(-/-) adults and wild-type siblings. Agonist- stimulated Ca2+ release from intracellular stores was assayed to identify signaling defects in primary cultures of thioglycolate-elicited macrophages isolated from Gα15(-/-) mice. C5a-stimulated phosphoinositide accumulation and Ca2+ release was significantly reduced in Gα15(-/-) macrophages. Ca2+ signaling was abolished only in mutant cells pretreated with pertussis toxin, suggesting that the C5a receptor couples to both Gα15 and Gαi in vivo. Signaling evoked by other receptors coupled by Gq class α subunits appeared normal in Gα15(-/-) macrophages. Despite discrete signaling defects, compensation by coexpressed Gq and/or Gi class α subunits may suppress abnormalities in Gα15-deficient mice.",
author = "I. Davignon and Catalina, {M. D.} and D. Smith and J. Montgomery and J. Swantek and J. Croy and M. Siegelman and Wilkie, {T. M.}",
year = "2000",
month = "2",
doi = "10.1128/MCB.20.3.797-804.2000",
language = "English (US)",
volume = "20",
pages = "797--804",
journal = "Molecular and Cellular Biology",
issn = "0270-7306",
publisher = "American Society for Microbiology",
number = "3",

}

TY - JOUR

T1 - Normal hematopoiesis and inflammatory responses despite discrete signaling defects in Gα15 knockout mice

AU - Davignon, I.

AU - Catalina, M. D.

AU - Smith, D.

AU - Montgomery, J.

AU - Swantek, J.

AU - Croy, J.

AU - Siegelman, M.

AU - Wilkie, T. M.

PY - 2000/2

Y1 - 2000/2

N2 - Gα15 activates phospholipase Cβ in response to the greatest variety of agonist-stimulated heptahelical receptors among the four Gq class G-protein α subunits expressed in mammals. Gα15 is primarily expressed in hematopoietic cells in fetal and adult mice. We disrupted the Gα15 gene by homologous recombination in embryonic stem cells to identify its biological functions. Surprisingly, hematopoiesis was normal in Gα15(-/-) mice, Gα15(- /-) Gαq(-/-) double-knockout mice (which express only Gα11 in most hematopoietic cells), and Gα11(-/-) mice, suggesting functional redundancy in Gq class signaling. Inflammatory challenges, including thioglycolate- induced peritonitis and infection with Trichinella spiralis, stimulated similar responses in Gα15(-/-) adults and wild-type siblings. Agonist- stimulated Ca2+ release from intracellular stores was assayed to identify signaling defects in primary cultures of thioglycolate-elicited macrophages isolated from Gα15(-/-) mice. C5a-stimulated phosphoinositide accumulation and Ca2+ release was significantly reduced in Gα15(-/-) macrophages. Ca2+ signaling was abolished only in mutant cells pretreated with pertussis toxin, suggesting that the C5a receptor couples to both Gα15 and Gαi in vivo. Signaling evoked by other receptors coupled by Gq class α subunits appeared normal in Gα15(-/-) macrophages. Despite discrete signaling defects, compensation by coexpressed Gq and/or Gi class α subunits may suppress abnormalities in Gα15-deficient mice.

AB - Gα15 activates phospholipase Cβ in response to the greatest variety of agonist-stimulated heptahelical receptors among the four Gq class G-protein α subunits expressed in mammals. Gα15 is primarily expressed in hematopoietic cells in fetal and adult mice. We disrupted the Gα15 gene by homologous recombination in embryonic stem cells to identify its biological functions. Surprisingly, hematopoiesis was normal in Gα15(-/-) mice, Gα15(- /-) Gαq(-/-) double-knockout mice (which express only Gα11 in most hematopoietic cells), and Gα11(-/-) mice, suggesting functional redundancy in Gq class signaling. Inflammatory challenges, including thioglycolate- induced peritonitis and infection with Trichinella spiralis, stimulated similar responses in Gα15(-/-) adults and wild-type siblings. Agonist- stimulated Ca2+ release from intracellular stores was assayed to identify signaling defects in primary cultures of thioglycolate-elicited macrophages isolated from Gα15(-/-) mice. C5a-stimulated phosphoinositide accumulation and Ca2+ release was significantly reduced in Gα15(-/-) macrophages. Ca2+ signaling was abolished only in mutant cells pretreated with pertussis toxin, suggesting that the C5a receptor couples to both Gα15 and Gαi in vivo. Signaling evoked by other receptors coupled by Gq class α subunits appeared normal in Gα15(-/-) macrophages. Despite discrete signaling defects, compensation by coexpressed Gq and/or Gi class α subunits may suppress abnormalities in Gα15-deficient mice.

UR - http://www.scopus.com/inward/record.url?scp=0033982576&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033982576&partnerID=8YFLogxK

U2 - 10.1128/MCB.20.3.797-804.2000

DO - 10.1128/MCB.20.3.797-804.2000

M3 - Article

VL - 20

SP - 797

EP - 804

JO - Molecular and Cellular Biology

JF - Molecular and Cellular Biology

SN - 0270-7306

IS - 3

ER -