A5101994143- Retinoids in leukemia and cellular processes
- Retinal Development and Disorders
- Fullerene Chemistry and Applications
- Retinal Diseases and Treatments
- Antioxidant Activity and Oxidative Stress
- Synthesis and Properties of Aromatic Compounds
- Graphene research and applications
- Estrogen and related hormone effects
- interferon and immune responses
- Virus-based gene therapy research
- Advanced Cellulose Research Studies
- Ion Transport and Channel Regulation
- Organic Chemistry Cycloaddition Reactions
- Photoreceptor and optogenetics research
- melanin and skin pigmentation
- Enzyme function and inhibition
- Enzyme Production and Characterization
- Microbial bioremediation and biosurfactants
- Advanced Fluorescence Microscopy Techniques
- Ocular Diseases and Behçet’s Syndrome
- Ion Channels and Receptors
- Nutrition, Genetics, and Disease
- Peroxisome Proliferator-Activated Receptors
- Cholesterol and Lipid Metabolism
- Connexins and lens biology
University of Havana
2013-2018
Rede de Química e Tecnologia
2014
University of California, Los Angeles
1995-2012
Doheny Eye Institute
2001-2009
Inserm
2008
Centre National de la Recherche Scientifique
2008
Institute of Neurobiology
2007
Harvard University
2000-2001
Centro de Ingeniería Genética y Biotecnología
1991
Uppsala University
1991
The enzyme responsible for conversion of all-trans-retinol into retinyl esters, the lecithin retinol acyltransferase (LRAT) has been characterized at molecular level. cDNA coding this protein was cloned and its amino acid sequence deduced. LRAT is composed a polypeptide 230 residues with calculated mass 25.3 kDa. Tissue distribution analysis by Northern blot showed expression 5.0-kilobase transcript in human retinal pigment epithelium as well other tissues that are known their high activity...
Cellobiose oxidase from the white rot fungus Phanerochaete chrysosporium has been purified to homogeneity by a new method. The enzyme cleaved papain into two fragments: one containing heme group and flavin group. fragment can oxidize cellobiose is reoxidized oxygen. binds cellulose approximately same extent as cellobiohydrolase I. cellulose‐binding site located on domain. cannot be totally displaced cellobiose, it still active when adsorbed cellulose. possible role of in lignocellulose...
We report generation of a mouse model in which the STRA6 gene has been disrupted functionally to facilitate study visual responses, changes ocular morphology, and retinoid processing under protein deficiency. METHODS.A null line, stra6 -/-, was generated.Western Blot immunocytochemistry were used determine expression protein.Visual responses morphological studies performed on 6-week, 5-month 10-month-old mice.The content eye tissues evaluated dark-adapted mice by high performance liquid...
Vertebrate retinas contain two types of light-detecting cells. Rods subserve vision in dim light, while cones provide color bright light. Both light-sensitive proteins called opsins. The light-absorbing chromophore most opsins is 11-cis-retinaldehyde, which isomerized to all-trans-retinaldehyde by absorption a photon. Restoration light sensitivity requires chemical re-isomerization retinaldehyde an enzymatic pathway the visual cycle retinal pigment epithelium. isomerase this uses...
purpose. To characterize molecular and cellular changes induced by sustained expression of ciliary neurotrophic factor (CNTF) in the rds mutant mouse retina. methods. Recombinant adeno-associated virus (rAAV) expressing CNTF was injected subretinally, for transduction peripherin/rds +/ − transgenic mice that carry P216L mutation found human retinitis pigmentosa. Characterization retinal neurons glia performed immunocytochemistry with cell-type–specific markers. Activation signaling molecules...
Somatic, targeted inactivation of the retinoid X receptor beta gene (Rxrb) in Sertoli cells (SC; yielding Rxrb(Ser-/-) mutants) leads to failure spermatid release, accumulation cholesterol esters and, subsequently, testis degeneration. These abnormalities are identical, their nature and kinetics, those observed upon inactivating Rxrb whole organism, thereby demonstrating that all reproductive functions RXRB carried out SC. The degeneration is a consequence ester cell overload occurring SC...
Lecithin retinol acyltransferase (LRAT) is an essential enzyme in vitamin A metabolism and mobilization. The membrane-bound catalyzes the transfer of acyl group from sn-1 position lecithin to generate retinyl esters. sequence LRAT novel hence does not suggest a mechanistic class which belongs. However, activity exceedingly sensitive affinity labeling group-specific reagents directed toward thiol groups. human retinal pigment epithelium has cysteine residues at positions 161, 168, 182, 208....
Lecithin retinol acyltransferase (LRAT) catalyzes the esterification of all-trans-retinol into all-trans-retinyl ester, an essential reaction in vertebrate visual cycle. Since esters are substrates for isomerization that generates 11-cis-retinoids, this is operation In addition, LRAT founder member a series proteins, which novel sequence and have unknown functions. Native integral membrane protein has never been purified. To obtain pure LRAT, N- C-transmembrane termini were deleted replaced...
To generate a mouse model in which the Lrat gene is selectively disrupted retinal pigment epithelium (RPE). evaluate effects on synthesis of retinyl esters and expression other proteins involved continuation visual cycle.A line part first exon has been flanked by loxP sites, was generated used study (Lrat(L3/L3) mice). Heterozygous mice (Lrat(+/L3)) were crossed with expressing Cre-recombinase under control tyrosinase-related protein-1 (Tyrp1) promoter, active melanin-synthesizing cells such...
Structural and conformational study of a new steroid derivative using X-ray density functional calculations.
The design and synthesis of fullerene–steroid hybrids by using Prato's protocol has afforded new fullerene derivatives endowed with epiandrosterone, an important naturally occurring steroid hormone. Since the formation pyrrolidine ring resulting from 1,3-dipolar cyloaddition reaction takes place generation a stereogenic center on C2 five-membered ring, proceeds diastereomeric mixture [compounds 6 7 in 70:30 ratio, 8 9 26:74 ratio (HPLC)] which major diasteroisomers is consistent...
New [60]fullerene-steroid conjugates (4–6) have been synthesized by 1,3-dipolar cycloaddition and Bingel–Hirsch cyclopropanation reactions from suitably functionalized epiandrosterone [60]fullerene. Since a new stereocenter is created in the formation of Prato monoaduct, two different diastereomers were isolated HPLC (4, 5) whose absolute configurations assigned according to highly reliable "sector rule" on fullerenes. A further reaction malonate-containing diastereomer 5 with second C60...
The diastereoselective synthesis of cis and trans steroid-fulleropyrrolidines hybrids by reaction N-metalated azomethine ylides [Cu(II) or Ag(I)] with the appropriate chiral ligand C60 is described. experimental findings reveal that ylide stabilized an allylic group cycloadds to [60]fullerene in efficient manner a good diastereomeric excess. Furthermore, new generated stereocenters are fully controlled catalytic systems used without being influenced chirality steroid. Interestingly, this...
Here we report on the self-organization characteristics in water of two diastereomer pairs fullerene–androsterone hybrids that have hydrophobic C 60 appendage A and D ring androsterone moiety, respectively. The morphology particle size aqueous solution were determined by transmission electron microscopy (TEM) dynamic light scattering (DLS), with satisfactory agreement between both techniques. In general, these fullerene derivatives are shown to organize into spherical nano-scale structures...
Lecithin retinol acyl transferase (LRAT) is a novel membrane bound enzyme that catalyzes the formation of retinyl esters from vitamin A and lecithin. The both essential for vision general mobilization A. sequence LRAT defines it as unrelated to any other protein known function. possesses catalytically active site cysteine residue. also contains six histidine residues. It shown here two these residues (H57 H163) are catalysis. mechanistic hypothesis presented account observations.