| Role of cysteine residues in cell surface expression of the human riboflavin transporter-2 (hRFT2) in intestinal epithelial cells. | |
| | |
MedLine Citation:
|
PMID: 21512156 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The water-soluble vitamin B2 (riboflavin, RF) is an essential micronutrient for normal cell function and survival. Recent studies have identified a role for the human riboflavin transporter-2 (hRFT2) in normal intestinal RF absorption. However, little is known about the cell biology of this transporter and specifically about the molecular determinant(s) that dictate its cell surface expression in human intestinal epithelial cells. Here we show that the full-length hRFT2 protein fused to green fluorescent protein (GFP) (GFP-hRFT2) is expressed exclusively at the apical membrane domain of Caco-2 cells. COOH-terminal sequence was essential in dictating cell surface expression with a specific role for conserved cysteine residues (C463 and C467). Mutation of C463 and C467 ablated RF uptake, explained by retention of the constructs within the endoplasmic reticulum. Modeling analysis suggested a potential disulfide bridge between C463 and C386. Consistent with this prediction, mutating the C386 site in the context of the full-length transporter resulted in intracellular retention, whereas mutation of another conserved cysteine (C326A) was without effect on hRFT2 targeting. Intracellular trafficking of hRFT2 was also examined and appeared to involve distinct vesicular structures, the motility of vesicles critically dependent on an intact microtubule network. These results demonstrate a potential role for specific cysteine residues in the cell surface expression of the hRFT2 in human intestinal epithelial cells. |
| | |
Authors:
|
Veedamali S Subramanian; Laramie Rapp; Jonathan S Marchant; Hamid M Said |
Related Documents
:
|
17266266 - Discrimination between single escherichia coli cells using time-resolved confocal spect... 16873446 - Halotag: a new versatile reporter gene system in plant cells. 20674576 - Immunostaining of atlantic salmon (salmo salar l.) leucocytes. 11559566 - Neuroblastic and schwannian stromal cells of neuroblastoma are derived from a tumoral p... 12591596 - Identification of a novel putative signaling center, the tertiary enamel knot in the po... 18440366 - A cell-microelectronic sensing technique for profiling cytotoxicity of chemicals. |
Publication Detail:
|
Type: Journal Article; Research Support, N.I.H., Extramural; Research Support, U.S. Gov't, Non-P.H.S. Date: 2011-04-21 |
Journal Detail:
|
Title: American journal of physiology. Gastrointestinal and liver physiology Volume: 301 ISSN: 1522-1547 ISO Abbreviation: Am. J. Physiol. Gastrointest. Liver Physiol. Publication Date: 2011 Jul |
Date Detail:
|
Created Date: 2011-06-29 Completed Date: 2011-09-06 Revised Date: 2012-09-24 |
Medline Journal Info:
|
Nlm Unique ID: 100901227 Medline TA: Am J Physiol Gastrointest Liver Physiol Country: United States |
Other Details:
|
Languages: eng Pagination: G100-9 Citation Subset: IM |
Affiliation:
|
Department of Medicine, University of California Medical School, Irvine, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Amino Acid Sequence Caco-2 Cells Cell Membrane / genetics, metabolism Cysteine / chemistry*, genetics Endoplasmic Reticulum / genetics, metabolism Humans Intestinal Mucosa / metabolism* Membrane Transport Proteins / biosynthesis, chemistry, genetics, metabolism* Molecular Sequence Data Mutation |
| Grant Support | |
ID/Acronym/Agency:
|
AA18071/AA/NIAAA NIH HHS; DK58057/DK/NIDDK NIH HHS; DK84094/DK/NIDDK NIH HHS; GM088790/GM/NIGMS NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Membrane Transport Proteins; 0/SLC52A3 protein, human; 52-90-4/Cysteine |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Colitis decreases mechanosensitive K2P channel expression and function in mouse colon sensory neuron...
Next Document: Polyamines mediate glutamine-dependent induction of the intestinal epithelial heat shock response.