Physiol. Genomics AJP: Gastrointestinal and Liver Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Physiol. Genomics 4: 147-153, 2000;
1094-8341/00 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via ISI Web of Science (3)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by SCARAFIA, L. E.
Right arrow Articles by SWINNEY, D. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by SCARAFIA, L. E.
Right arrow Articles by SWINNEY, D. C.
Received 21 July 2000; accepted in final form 10 October 2000.
Physiological Genomics 4:147-153 (2000)
1094-8341/00 $5.00 © 2000 American Physiological Society

Quantitative expression analysis of the cellular specificity of HECT-domain ubiquitin E3 ligases

LILIANA E. SCARAFIA, ANDREAS WINTER and DAVID C. SWINNEY

Inflammatory Diseases Unit, Roche Bioscience, Palo Alto, California 94304

We evaluated the expression of 28 gene sequences with homology to the carboxy terminal of HECT E3 ubiquitin ligases in nine human cell lines using RT-PCR, to determine whether gene expression could be associated with cell-specific functions (HECT is "homologous to E6AP C-terminus"). In general, HECT-domain E3 ligases are constitutively expressed at low levels with a broad range between cell types. hecth3, 21, and 23 had higher levels in three leukocytic lines (Jurkat, MM6, THP1); hecth11 was more abundant in HepG2 and A495; and hecth15 and hecth12 were differentially expressed in lung fibroblasts derived from normal and severe emphysema patients (CCD16 and CCD29, respectively). Absolute quantitation showed that most HECT E3s have about 20–100 copies of mRNA per Jurkat cell. By comparison, UBCH7 (an ubiquitin-conjugating E2) is 10-fold more abundant in Jurkat cells and 30-fold more abundant than E2 UBCH5A. We interpret the broad range of transcript levels to be consistent with the hypothesis that the concentrations of E3 are important for ubiquitination selectivity, leading us to conclude that substrate activation is necessary but not sufficient for selectivity.

TaqMan polymerase chain reaction; expression profiling; messenger RNA quantitation; ubiquitin E3 ligase; HECT






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online