Back to Search
Start Over
Structure of the STRA6 receptor for retinol uptake.
- Source :
-
Science . 8/26/2016, Vol. 353 Issue 6302, paad8266-1-aad8266-12. 12p. 3 Color Photographs, 1 Diagram, 1 Chart, 1 Graph. - Publication Year :
- 2016
-
Abstract
- Vitamin A homeostasis is critical to normal cellular function. Retinol-binding protein (RBP) is the sole specific carrier in the bloodstream for hydrophobic retinol, the main form in which vitamin A is transported. The integral membrane receptor STRA6 mediates cellular uptake of vitamin A by recognizing RBP-retinol to trigger release and internalization of retinol. We present the structure of zebrafish STRA6 determined to 3.9-angstrom resolution by single-particle cryo-electron microscopy. STRA6 has one intramembrane and nine transmembrane helices in an intricate dimeric assembly. Unexpectedly, calmodulin is bound tightly to STRA6 in a noncanonical arrangement. Residues involved with RBP binding map to an archlike structure that covers a deep lipophilic cleft. This cleft is open to the membrane, suggesting a possible mode for internalization of retinol through direct diffusion into the lipid bilayer. [ABSTRACT FROM AUTHOR]
- Subjects :
- *VITAMIN A
*CELL receptors
*ZEBRA danio
*MICROSCOPY
*GENETICS
Subjects
Details
- Language :
- English
- ISSN :
- 00368075
- Volume :
- 353
- Issue :
- 6302
- Database :
- Academic Search Index
- Journal :
- Science
- Publication Type :
- Academic Journal
- Accession number :
- 117776019
- Full Text :
- https://doi.org/10.1126/science.aad8266