scholarly journals Structures of holo wild-type human cellular retinol-binding protein II (hCRBPII) bound to retinol and retinal

2014 ◽  
Vol 70 (12) ◽  
pp. 3226-3232 ◽  
Author(s):  
Zahra Nossoni ◽  
Zahra Assar ◽  
Ipek Yapici ◽  
Meisam Nosrati ◽  
Wenjing Wang ◽  
...  
Keyword(s):  
Intracellular Transport ◽  
Binding Protein ◽  
Binding Pocket ◽  
Lipid Binding ◽  
Retinol Binding Protein ◽  
Binding Affinities ◽  
Wild Type ◽  
Intracellular Lipid ◽  
X Ray ◽  
Cellular Retinol Binding Protein

Cellular retinol-binding proteins (CRBPs) I and II, which are members of the intracellular lipid-binding protein (iLBP) family, are retinoid chaperones that are responsible for the intracellular transport and delivery of both retinol and retinal. Although structures of retinol-bound CRBPI and CRBPII are known, no structure of a retinal-bound CRBP has been reported. In addition, the retinol-bound human CRBPII (hCRBPII) structure shows partial occupancy of a noncanonical conformation of retinol in the binding pocket. Here, the structure of retinal-bound hCRBPII and the structure of retinol-bound hCRBPII with retinol fully occupying the binding pocket are reported. It is further shown that the retinoid derivative seen in both the zebrafish CRBP and the hCRBPII structures is likely to be the product of flux-dependent and wavelength-dependent X-ray damage during data collection. The structures of retinoid-bound CRBPs are compared and contrasted, and rationales for the differences in binding affinities for retinal and retinol are provided.

scholarly journals Cellular retinol-binding protein type III is a PPARγ target gene and plays a role in lipid metabolism

2008 ◽  
Vol 295 (6) ◽  
pp. E1358-E1368 ◽  
Author(s):  
Cynthia F. Zizola ◽  
Gary J. Schwartz ◽  
Silke Vogel
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Free Fatty Acid ◽  
Target Gene ◽  
Binding Protein ◽  
Retinol Binding Protein ◽  
Wild Type ◽  
Type Iii ◽  
Cellular Retinol Binding Protein

Cellular retinol-binding protein (CRBP) type III (CRBP-III) belongs to the family of intracellular lipid-binding proteins, which includes the adipocyte-binding protein aP2. In the cytosol, CRBP-III binds retinol, the precursor of retinyl ester and the active metabolite retinoic acid. The goal of the present work is to understand the regulation of CRBP-III expression and its role in lipid metabolism. Using EMSAs, luciferase reporter assays, and chromatin immunoprecipitation assays, we found that CRBP-III is a direct target of peroxisome proliferator-activated receptor-γ (PPARγ). Moreover, CRBP-III expression was induced in adipose tissue of mice after treatment with the PPARγ agonist rosiglitazone. To examine a potential role of CRBP-III in regulating lipid metabolism in vivo, CRBP-III-deficient (C-III-KO) mice were maintained on a high-fat diet (HFD). Hepatic steatosis was decreased in HFD-fed C-III-KO compared with HFD-fed wild-type mice. These differences were partly explained by decreased serum free fatty acid levels and decreased free fatty acid efflux from adipose tissue of C-III-KO mice. In addition, the lack of CRBP-III was associated with reduced food intake, increased respiratory energy ratio, and altered body composition, with decreased adiposity and increased lean body mass. Furthermore, expression of genes involved in mitochondrial fatty acid oxidation in brown adipose tissue was increased in C-III-KO mice, and C-III-KO mice were more cold tolerant than wild-type mice fed an HFD. In summary, we demonstrate that CRBP-III is a PPARγ target gene and plays a role in lipid and whole body energy metabolism.

scholarly journals Expression, characterization and engineered specificity of rat epididymal retinoic acid-binding protein

1998 ◽  
Vol 334 (1) ◽  
pp. 155-160 ◽  
Author(s):  
Manickavasagam SUNDARAM ◽  
Asipu SIVAPRASADARAO ◽  
Daan M. F. van AALTEN ◽  
John B. C. FINDLAY
Keyword(s):  
Retinoic Acid ◽  
Double Mutant ◽  
Binding Protein ◽  
Binding Pocket ◽  
Retinol Binding Protein ◽  
Wild Type ◽  
Serum Retinol ◽  
Recognition Sequence ◽  
Acid Binding Protein ◽  
Charged Residues

Epididymal retinoic acid-binding protein (ERABP) is the major androgen-dependent protein present in the lumen of the epididymis and is thought to be involved in sperm maturation. It displays a high degree of three-dimensional structural similarity to serum retinol-binding protein (RBP). Although both proteins interact with retinoids, RBP exhibits a broad specificity, binding retinol, retinoic acid and retinaldehyde with roughly equal affinities, whereas ERABP is specific for all-trans- and 9-cis-retinoic acids. Consistent with this, the binding pockets of the two proteins are different: in RBP it is predominantly hydrophobic, whereas that for ERABP is amphipathic, with a network of charged residues at the open end of the binding pocket. In order to investigate the roles of these charged residues, Arg-80 and Glu-63 have been mutated to isoleucine. The resultant double mutant, Glu-63 → Ile/Arg-80 → Ile, as well as the wild-type protein, were subsequently expressed in Escherichia coli as fusion proteins, with the streptavidin recognition sequence (Strep) tagged to their C-termini. The expressed proteins were purified in a single step by streptavidin-affinity chromatography and their ligand-binding properties were examined using fluorimetric titrations. Whereas the wild-type ERABP binds only retinoic acid, the double mutant is capable of binding retinol, retinoic acid and retinaldehyde with similar affinities. These observations provide experimental support for the proposition that the charged residues near the open end of the binding pocket are responsible for restricting the specificity of ERABP for retinoic acid. These studies demonstrate that changes in specificity can be engineered into lipocalins.

scholarly journals Molecular basis for the interaction of cellular retinol binding protein 2 (CRBP2) with nonretinoid ligands

2021 ◽  
Vol 62 ◽  
pp. 100054
Author(s):  
Josie A. Silvaroli ◽  
Jacqueline Plau ◽  
Charlie H. Adams ◽  
Surajit Banerjee ◽  
Made Airanthi K. Widjaja-Adhi ◽  
...  
Keyword(s):  
Molecular Basis ◽  
Binding Protein ◽  
Retinol Binding Protein ◽  
Cellular Retinol Binding Protein

The transfer of transthyretin and receptor-binding properties from the plasma retinol-binding protein to the epididymal retinoic acid-binding protein

2002 ◽  
Vol 362 (2) ◽  
pp. 265-271 ◽  
Author(s):  
Manickavasagam SUNDARAM ◽  
Daan M. F. van AALTEN ◽  
John B. C. FINDLAY ◽  
Asipu SIVAPRASADARAO
Keyword(s):  
Retinoic Acid ◽  
Binding Protein ◽  
Binding Pocket ◽  
Retinol Binding Protein ◽  
Cell Surface Receptor ◽  
Acid Binding Protein ◽  
The Family ◽  
Surface Receptor ◽  
A Cell ◽  
Plasma Retinol

Members of the lipocalin superfamily share a common structural fold, but differ from each other with respect to the molecules with which they interact. They all contain eight β-strands (A—H) that fold to form a well-defined β-barrel, which harbours a binding pocket for hydrophobic ligands. These strands are connected by loops that vary in size and structure and make up the closed and open ends of the pocket. In addition to binding ligands, some members of the family interact with other macromolecules, the specificity of which is thought to be associated with the variable loop regions. Here, we have investigated whether the macromolecular-recognition properties can be transferred from one member of the family to another. For this, we chose the prototypical lipocalin, the plasma retinol-binding protein (RBP) and its close structural homologue the epididymal retinoic acid-binding protein (ERABP). RBP exhibits three molecular-recognition properties: it binds to retinol, to transthyretin (TTR) and to a cell-surface receptor. ERABP binds retinoic acid, but whether it interacts with other macromolecules is not known. Here, we show that ERABP does not bind to TTR and the RBP receptor, but when the loops of RBP near the open end of the pocket (L-1, L-2 and L-3, connecting β-strands A—B, C—D and E—F, respectively) were substituted into the corresponding regions of ERABP, the resulting chimaera acquired the ability to bind TTR and the receptor. L-2 and L-3 were found to be the major determinants of the receptor- and TTR-binding specificities respectively. Thus we demonstrate that lipocalins serve as excellent scaffolds for engineering novel biological functions.

Fluorescence studies of rat cellular retinol binding protein II produced in Escherichia coli: an analysis of four tryptophan substitution mutants

Biochemistry ◽  
1992 ◽  
Vol 31 (8) ◽  
pp. 2376-2383 ◽  
Author(s):  
Bruce C. Locke ◽  
Jean M. MacInnis ◽  
Shi Jun Qian ◽  
Jeffrey I. Gordon ◽  
Ellen Li ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Binding Protein ◽  
Retinol Binding Protein ◽  
Fluorescence Studies ◽  
Cellular Retinol Binding Protein

scholarly journals Teq I RFLP in the human cellular retinol-binding protein (CRBP) gene

1988 ◽  
Vol 16 (15) ◽  
pp. 7758-7758
Author(s):  
A. Pellegrino ◽  
S. Garofalo ◽  
S. Cocozza ◽  
A. Monticelli ◽  
R. Faraonio ◽  
...  
Keyword(s):  
Binding Protein ◽  
Retinol Binding Protein ◽  
Cellular Retinol Binding Protein
Sign in / Sign up

Export Citation Format

Share Document