Retinal binding proteins

Bieszke, J. A., E. L. Braun et al. (1999). The nop-1 gene of Neurospora crassa encodes a seven transmembrane helix retinal-binding protein homologous to archaeal rhodopsins. Proc. Natl. Acad. Sci. 96(14) 8034-8039. 

Hydrolysis of retinyl ester to retinol occurs in the lumen of the small intestine from where it is absorbed with the aid of bile salts, esterified to form retinyl ester and then released into lymph where it is incorporated into chylomicrons. The action of lipoprotein lipase converts chylomicrons to remnants and the retinyl ester remains in the remnants to be taken up by the Uver, where it is stored as the ester until required. On release from the liver, it is transported in blood bound to retinal binding-protein. 

Plasma retinal-binding protein precursor Senescence marker protein-30... 

Carotenoids are plant pigments which constitute more than 600 compounds, most of them being lipid-soluble and which contribute significantly to the nutritional benefits of fruit and vegetable consumption. f)-carotene is the most common form of the vitamin and is the precursor of vitamin A. f)-cryptoxanthine is another precursor of vitamin A. The latter is a powerful lipid-soluble antioxidant which protects cellular membranes from oxidative stress. Vitamin A is carried into the plasma by retinal binding protein which is synthesized in the liver. 

CRalBP cellular retinal binding protein (retinaldehyde binding protein 1 RLBPl)... 

The functional changes in chronic lead nephropathy appear to be less specific than those observed in acute poisoning. As in other forms of interstitial nephritis, proteinuria and glycosuria are initially absent. In contrast to cadmium nephropathy, the excretion of a large array of urinary marker proteins such as retinal binding protein, lysozyme, and iriicroglobulin [33, 34] is not increased in the absence of a reduced GFR. 

Although they are not related, photoactive yellow protein (PYP), green fluorescent protein (GFP), and phytochromes are all discussed in this chapter that deals with the cis-trans isomerization (CTI) of non-retinal binding proteins. All three systems contain a chromophore that is attached to the protein and that undergoes CTI. In this chapter we attempt to provide the reader with a brief introduction to PYP, GFP, and phytochromes, and present a summary of the current understanding of the CTIs that are central to the photochemistry observed in these systems. 

Bernard AM, Moreau D, Lauwerys R. Comparison of retinal binding protein and 3-2-microglobin in urine for the early detection of tubular proteinuria. Clin Chim Acta 1982 116 1-7. 

Beetham R, Dawanay A, Landon J, Cattell R. A radioimmunoassay for retinal-binding protein in serum and urine. Clin Chem 1985 31 1364-1367. 

Adeqnate zinc provides normal growth and tissue repair. In patients receiving total parenteral nutrition with low plasma levels of zinc, dermatitis has been followed by alopecia. Zinc is an integral part of many enzymes important to carbohydrate and protein mobilization of retinal-binding protein. 

Figure 16.55. Ribbon structure of the native form of the cellular retinal binding protein l(CRABPI), Reprinted, with permission, from Ref. 117. Copyright 1996. Cambridge University Press.

Vitamin A is transported from the gut to the liver in chylomicrons, and from the Hver to the tissues bound to a specific retinal-binding protein or pre-albumin. Deficiency of vitamin A is usually associated with poor protein diets. It is not necessarily reversible by administration of vitamin A alone since the synthesis of retinolbinding protein is affected by the deficiency and therefore so is vitamin A absorption. Deficiency may cause night blindness, xerophthalmia and keratomalacia. Vitamin A toxicity is unUkely with a normal diet but can cause dermatitis, hair loss, and hepatic dysfunction. In pregnancy it can cause teratogenicity if taken in... 

Plasma retinol is transported by a specific 21-kDa transport protein, retinal binding protein (RBP). Most RBP is produced in the liver, but some extra-hepatic organs also synthesize it. Each molecule of RBP binds one molecule of all-tra s-retinol nonco-valently. In plasma, the retinol-RBP complex (holo-RBP) forms a larger complex with a cotransport... 

Intracellular binding protein 11-ds-Retinal-binding protein... 

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