Document Detail


Vaccinia-T7 RNA polymerase expression system: evaluation for the expression cloning of plasma membrane transporters.
MedLine Citation:
PMID:  1862934     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The vaccinia/T7 transient expression system, which results in rapid, high-level expression of proteins encoded by plasmids bearing T7 promoters, provides a powerful strategy for the expression cloning of membrane transporters. To test the feasibility of this approach, we introduced the rabbit Na+/glucose transporter by liposome-mediated transfection into vaccinia infected HeLa cells and determined the characteristics and sensitivity of induced [14C]alpha-methyl D-glucopyranoside uptake. We observed a rapid (4-12 h) expression of saturable (Kt = 342 microM) [14C]alpha-methyl D-glucopyranoside uptake following transfection, with substrate and inhibitor sensitivities of the native carrier, including Na+ and temperature dependence and appropriate phloridzin sensitivity (KI = 9.1 microM). The time-dependent increase in alpha-methyl D-glucopyranoside uptake coincided with a decline in endogenous Na+/D-aspartate transport. Maximal levels of expression achieved were nearly 10-fold higher than that reported for transient expression of Na+/glucose transporters in the COS cell system. Rate and dilution estimates demonstrates a sensitivity of detection of single clones diluted several thousand fold by nonspecific plasmid DNA. A further 3-fold increase in transport sensitivity was achieved after transfection of plasmid constructs bearing additional 5'-T7 stem-loop and 3'-T7 termination signals. When cell lines with low endogenous transport were coupled with substrates of high specific activity, as with measurements of induced [3H]gamma-aminobutyric acid uptake, we were able to detect expression from transporter bearing plasmids diluted as much as 10,000-fold by non-specific plasmid DNA.(ABSTRACT TRUNCATED AT 250 WORDS)
Authors:
R D Blakely; J A Clark; G Rudnick; S G Amara
Related Documents :
10869574 - Aquaporin 3 cloned from xenopus laevis is regulated by the cystic fibrosis transmembran...
12759754 - The slc20 family of proteins: dual functions as sodium-phosphate cotransporters and vir...
9592064 - Cystic fibrosis transmembrane conductance regulator expression in human hypothalamus.
9328474 - Higher proportion of intact exon 9 cftr mrna in nasal epithelium compared with vas defe...
11027494 - Identification of a novel human mitochondrial d-loop rna species which exhibits upregul...
23228634 - Microrna regulation of epithelial plasticity in cancer.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Analytical biochemistry     Volume:  194     ISSN:  0003-2697     ISO Abbreviation:  Anal. Biochem.     Publication Date:  1991 May 
Date Detail:
Created Date:  1991-08-30     Completed Date:  1991-08-30     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0370535     Medline TA:  Anal Biochem     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  302-8     Citation Subset:  IM    
Affiliation:
Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06510.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Base Sequence
Carrier Proteins / genetics*,  metabolism
Cell Membrane / metabolism
Cloning, Molecular / methods*
DNA
DNA-Directed RNA Polymerases / genetics*
Genetic Vectors*
Hela Cells
Humans
Kinetics
Molecular Sequence Data
Monosaccharide Transport Proteins / genetics,  metabolism
Rabbits
Transfection
Vaccinia virus / genetics*
Viral Proteins
Grant Support
ID/Acronym/Agency:
5 T32 GM07324-14/GM/NIGMS NIH HHS
Chemical
Reg. No./Substance:
0/Carrier Proteins; 0/Monosaccharide Transport Proteins; 0/Viral Proteins; 9007-49-2/DNA; EC 2.7.7.-/bacteriophage T7 RNA polymerase; EC 2.7.7.6/DNA-Directed RNA Polymerases

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Enzyme-amplified rate conductimetric immunoassay.
Next Document:  Isolation of intact mitochondria and hepatocytes using vibration.