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
Drug Metabolism & Disposition
  • 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
Drug Metabolism & Disposition

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 dmd on Facebook
  • Follow dmd on Twitter
  • Follow ASPET on LinkedIn
Research ArticleArticle

How Many and Which Amino Acids Are Responsible for the Large Activity Differences between the Highly Homologous UDP-Glucuronosyltransferases (UGT) 1A9 and UGT1A10?

Katriina Itäaho, Liisa Laakkonen and Moshe Finel
Drug Metabolism and Disposition April 2010, 38 (4) 687-696; DOI: https://doi.org/10.1124/dmd.109.031229
Katriina Itäaho
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Liisa Laakkonen
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Moshe Finel
  • 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 + SI
  • PDF
Loading

Abstract

The amino acid sequences of the human UDP-glucuronosyltransferases (UGTs) 1A9 and 1A10 are 93% identical, yet there are large differences in their activity and substrate selectivity. For example, the regioselectivity in propranolol glucuronidation, the regioselectivity in dobutamine glucuronidation, and the glucuronidation rate of α- and β-estradiol differ greatly between UGT1A9 and UGT1A10. To identify the residue responsible for the activity differences, we divided the N-terminal half of the two UGTs into five comparable segments by inserting four unique restriction sites at identical positions in both genes and constructing chimeras in which segments of UGT1A9 were individually replaced by the corresponding segments from UGT1A10. Activity analyses of the resulting mutants, 910A [1A10(1–83)/1A9(84–285)], 910B [1A9(1–83)/1A10(84–147)/1A9(148–285)], 910C [1A9(1–147)/1A10(148–181)/1A9(182–285)], 910D [1A9(1–181)/1A10(182–235)/1A9(236–285)], and 910E [1A9(1–235)/1A10(236–285)] indicated that more than one residue is responsible for the differences between UGT1A9 and UGT1A10. We next prepared four double chimeras, in which two of the above UGT1A9 segments were replaced simultaneously by the corresponding UGT1A10 segments. However, none of the double chimeras glucuronidated either estradiol, propranolol, or dobutamine at rates that resembled those of UGT1A10. On the other hand, studying the kinetics of 1-naphthol glucuronidation yielded more focused results, indicating that residues within segment B (84–147) contribute directly to the Km value for this substrate. Further mutagenesis and activity assays suggested that Phe117 of UGT1A9 participates in 1-naphthol binding. In addition, it appears that residues within segment C of the N-terminal domain, mainly at positions 152 and 169, contribute to the higher glucuronidation rates of UGT1A10.

Footnotes

  • This study was supported by funding from the Sigrid Juselius Foundation (to M.F.); and the Magnus Ehrnrooth Foundation (to L.L.).

  • Article, publication date, and citation information can be found at http://dmd.aspetjournals.org.

    doi:10.1124/dmd.109.031229.

  • ↵Embedded Image The online version of this article (available at http://dmd.aspetjournals.org) contains supplemental material.

  • UGT
    UDP-glucuronosyltransferase
    UDPGA
    UDP-glucuronic acid
    HPLC
    high-performance liquid chromatography
    DMSO
    dimethyl sulfoxide.

    • Received November 17, 2009.
    • Accepted January 20, 2010.
  • Copyright © 2010 by The American Society for Pharmacology and Experimental Therapeutics
View Full Text

 

DMD 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

Drug Metabolism and Disposition: 38 (4)
Drug Metabolism and Disposition
Vol. 38, Issue 4
1 Apr 2010
  • Table of Contents
  • Table of Contents (PDF)
  • About the Cover
  • Index by author
  • Back Matter (PDF)
  • Editorial Board (PDF)
  • Front Matter (PDF)
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for sharing this Drug Metabolism & Disposition 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.
How Many and Which Amino Acids Are Responsible for the Large Activity Differences between the Highly Homologous UDP-Glucuronosyltransferases (UGT) 1A9 and UGT1A10?
(Your Name) has forwarded a page to you from Drug Metabolism & Disposition
(Your Name) thought you would be interested in this article in Drug Metabolism & Disposition.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Research ArticleArticle

How Many and Which Amino Acids Are Responsible for the Large Activity Differences between the Highly Homologous UDP-Glucuronosyltransferases (UGT) 1A9 and UGT1A10?

Katriina Itäaho, Liisa Laakkonen and Moshe Finel
Drug Metabolism and Disposition April 1, 2010, 38 (4) 687-696; DOI: https://doi.org/10.1124/dmd.109.031229

Citation Manager Formats

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

Share
Research ArticleArticle

How Many and Which Amino Acids Are Responsible for the Large Activity Differences between the Highly Homologous UDP-Glucuronosyltransferases (UGT) 1A9 and UGT1A10?

Katriina Itäaho, Liisa Laakkonen and Moshe Finel
Drug Metabolism and Disposition April 1, 2010, 38 (4) 687-696; DOI: https://doi.org/10.1124/dmd.109.031229
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
    • References
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF + SI
  • PDF

Related Articles

Cited By...

More in this TOC Section

  • Determination of Acyl-, O-, and N-Glucuronide
  • TMDD Affects PK of IL-10 Fc-fusion Proteins
  • Uptake as the RDS in Pevonedistat Hepatic Clearance
Show more Articles

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

ASPET's Other Journals

  • Journal of Pharmacology and Experimental Therapeutics
  • Molecular Pharmacology
  • Pharmacological Reviews
  • Pharmacology Research & Perspectives
ISSN 1521-009X (Online)

Copyright © 2022 by the American Society for Pharmacology and Experimental Therapeutics