Skip to main content
Advertisement

Main menu

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET

User menu

  • My alerts
  • Log in
  • My Cart

Search

  • Advanced search
Molecular Pharmacology
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET
  • My alerts
  • Log in
  • My Cart
Molecular Pharmacology

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Visit molpharm on Facebook
  • Follow molpharm on Twitter
  • Follow molpharm on LinkedIn
Research ArticleArticle

β2-Adrenergic Receptor Lacking the Cyclic AMP-Dependent Protein Kinase Consensus Sites Fully Activates Extracellular Signal-Regulated Kinase 1/2 in Human Embryonic Kidney 293 Cells: Lack of Evidence for Gs/Gi Switching.

Jacqueline Friedman, Bonita Babu and Richard B. Clark
Molecular Pharmacology November 2002, 62 (5) 1094-1102; DOI: https://doi.org/10.1124/mol.62.5.1094
Jacqueline Friedman
Department of Integrative Biology and Pharmacology, the University of Texas Health Science Center at Houston Medical School, Houston, Texas
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Bonita Babu
Department of Integrative Biology and Pharmacology, the University of Texas Health Science Center at Houston Medical School, Houston, Texas
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Richard B. Clark
Department of Integrative Biology and Pharmacology, the University of Texas Health Science Center at Houston Medical School, Houston, Texas
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF
Loading

Abstract

Stimulation of the β2-adrenergic receptor (β2AR) in human embryonic kidney (HEK) 293 cells causes a transient activation of Extracellular Signal-Regulated Kinase (ERK) 1/2. One of the mechanisms proposed for this activation is a PKA-mediated phosphorylation of the β2AR that switches receptor coupling from Gs to Gi and triggers internalization of the receptor. To examine these phenomena, we characterized agonist activation of ERK1/2 in HEK293 cells by the endogenous β2AR and in HEK293 cells stably overexpressing either the wild-type β2AR or a substitution mutant β2AR (PKA−) that lacks the cyclic AMP-dependent protein kinase (PKA) consensus phosphorylation sites (S261A, S262A and S345A, S346A). As the baseline, we established that epinephrine stimulation of the endogenous β2AR in HEK293 cells (20–30 fmol/mg) caused a rapid and transient activation of ERK1/2 with an EC50 of 5 to 6 nM. In contrast, the potency of epinephrine stimulation of ERK1/2 in cells stably overexpressing WTβ2AR and PKA− (2–4 pmol of β2AR/mg) was increased by over 100-fold relative to HEK293 cells, the EC50 values being 20 to 60 pM. The nearly identical 100-fold shift in EC50 for ERK1/2 activation in the PKA− and WTβ2AR relative to that in the HEK293 showed that the PKA− are fully capable of activating ERK1/2. We also found maximal activation of ERK1/2 in the overexpressing cell lines at concentrations of epinephrine that cause no internalization (i.e., the EC50 for internalization was 75 nM). Pertussis toxin pretreatment caused only a weak inhibition of epinephrine activation of ERK1/2 in the HEK293 (7–16%) and no inhibition in the PKA− cells. Finally we found that the Src family kinase inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (10 μM) caused a >90% inhibition of epinephrine or forskolin activation of ERK1/2 in both cell lines. Our results indicate that the dominant mechanism of β2AR activation of ERK1/2 does not require PKA phosphorylation of the β2AR, receptor internalization or switching from activation of Gs to Gi but clearly requires activation of a Src family member that may be downstream of PKA.

  • The American Society for Pharmacology and Experimental Therapeutics
View Full Text

MolPharm articles become freely available 12 months after publication, and remain freely available for 5 years. 

Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page. 

 

  • Click here for information on institutional subscriptions.
  • Click here for information on individual ASPET membership.

 

Log in using your username and password

Forgot your user name or password?

Purchase access

You may purchase access to this article. This will require you to create an account if you don't already have one.
PreviousNext
Back to top

In this issue

Molecular Pharmacology: 62 (5)
Molecular Pharmacology
Vol. 62, Issue 5
1 Nov 2002
  • Table of Contents
  • About the Cover
  • Index by author
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for sharing this Molecular Pharmacology article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
β2-Adrenergic Receptor Lacking the Cyclic AMP-Dependent Protein Kinase Consensus Sites Fully Activates Extracellular Signal-Regulated Kinase 1/2 in Human Embryonic Kidney 293 Cells: Lack of Evidence for Gs/Gi Switching.
(Your Name) has forwarded a page to you from Molecular Pharmacology
(Your Name) thought you would be interested in this article in Molecular Pharmacology.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Research ArticleArticle

β2-Adrenergic Receptor Lacking the Cyclic AMP-Dependent Protein Kinase Consensus Sites Fully Activates Extracellular Signal-Regulated Kinase 1/2 in Human Embryonic Kidney 293 Cells: Lack of Evidence for Gs/Gi Switching.

Jacqueline Friedman, Bonita Babu and Richard B. Clark
Molecular Pharmacology November 1, 2002, 62 (5) 1094-1102; DOI: https://doi.org/10.1124/mol.62.5.1094

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero

Share
Research ArticleArticle

β2-Adrenergic Receptor Lacking the Cyclic AMP-Dependent Protein Kinase Consensus Sites Fully Activates Extracellular Signal-Regulated Kinase 1/2 in Human Embryonic Kidney 293 Cells: Lack of Evidence for Gs/Gi Switching.

Jacqueline Friedman, Bonita Babu and Richard B. Clark
Molecular Pharmacology November 1, 2002, 62 (5) 1094-1102; DOI: https://doi.org/10.1124/mol.62.5.1094
del.icio.us logo Digg logo Reddit logo Twitter logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Abstract
    • Materials and Methods
    • Results
    • Discussion
    • Acknowledgments
    • Footnotes
    • Abbreviations
    • References
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF

Related Articles

Cited By...

More in this TOC Section

  • Fatty acid amide hydrolase in cisplatin nephrotoxicity
  • eCB Signaling System in hiPSC-Derived Neuronal Cultures
  • Benzbromarone relaxes airway smooth muscle via BK activation
Show more Article

Similar Articles

Advertisement
  • Home
  • Alerts
Facebook   Twitter   LinkedIn   RSS

Navigate

  • Current Issue
  • Fast Forward by date
  • Fast Forward by section
  • Latest Articles
  • Archive
  • Search for Articles
  • Feedback
  • ASPET

More Information

  • About Molecular Pharmacology
  • Editorial Board
  • Instructions to Authors
  • Submit a Manuscript
  • Customized Alerts
  • RSS Feeds
  • Subscriptions
  • Permissions
  • Terms & Conditions of Use

ASPET's Other Journals

  • Drug Metabolism and Disposition
  • Journal of Pharmacology and Experimental Therapeutics
  • Pharmacological Reviews
  • Pharmacology Research & Perspectives
ISSN 1521-0111 (Online)

Copyright © 2023 by the American Society for Pharmacology and Experimental Therapeutics