| Description | Leptin (aka OB protein, or Obesity factor protein) is a 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.:Leptin (humanLeptin (aka OB protein, or Obesity factor protein) is a 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.:Leptin (human), (recombinant) is produced in E.Coli as a single, non-glycosylated, polypeptide chain containing 146 amino acids and having a molecular mass of approximately 16 kDa. The Leptin protein is purified by proprietary chromatographic techniques.:Biological Activity is evidenced by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor.Product descriptionEncoded by the ob (obese) gene, Leptin is an adipose-derived cytokine that suppresses appetite and increases thermogenesis. Leptin exerts its anorectic effect via signaling through a hypothalamic receptor termed OB-R. Leptin has been shown to reduce body weight, food consumption, and plasma glucose levels in various in vivo models. Recombinant Human Leptin is a 16.0 kDa protein containing 147 amino acid residues.SourceE.coliSynonymsObesity protein (OB)AA SequenceMVPIQKVQDD TKTLIKTIVT RINDISHTQS VSSKQKVTGL DFIPGLHPIL TLSKMDQTLA VYQQILTSMP SRNVIQISND LENLRDLLHV LAFSKSCHLP WASGLETLDS LGGVLEASGY STEVVALSRL QGSLQDMLWQ LDLSPGCPurity:≥ 97% by SDS-PAGE gelBiological ActivityFully biologically active when compared to standard. The ED50 as determined by a chemotaxis bioassay using human Leptin R transfected BaF3 murine proB cells is less than 2 ng/ml, corresponding to a specific activity of > 5.0 × 105 IU/mgAccession NumberP41159Gene ID3952FormulationLyophilized from a 0.2 µm filtered concentrated solution in 50 mm PB, pH 3.5, with 0.02 % Tween-20.ReconstitutionWe recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1 % BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20 °C. Further dilutions should be made in appropriate buffered solutions... Read More | Product introduction：The additive contains a variety of cytokines, human albumin and other components. In order to ensure the activity, it is recommended that the additive part be thawed once and then sub packaged and frozen again. It is not advisable to freeze and thaw repeatedly. The Product introduction：The additive contains a variety of cytokines, human albumin and other components. In order to ensure the activity, it is recommended that the additive part be thawed once and then sub packaged and frozen again. It is not advisable to freeze and thaw repeatedly. The product contains no animal serum or animal serum components, no animal protein components, and no antibiotics.Matters needing attention：1. try to reduce the number of repeated freezing and thawing to avoid efficiency decline. 2. it is not suitable to place it at room temperature for a long time. 3. pay attention to aseptic operation and try to avoid pollution. 4. please wear experimental clothes and disposable gloves for operationScope of application：Cell culture additives... Read More | Inquire | Reverse transcriptases are enzymes encoded in retroviruses viral genome. The enzyme is responsible for transcription of the viral RNA to produce a dsDNA that can be inserted into the host genome.Reverse transcriptases are multifunctional enzymes. These enzymes exhibit an RNA and DNA directed Reverse transcriptases are enzymes encoded in retroviruses viral genome. The enzyme is responsible for transcription of the viral RNA to produce a dsDNA that can be inserted into the host genome.Reverse transcriptases are multifunctional enzymes. These enzymes exhibit an RNA and DNA directed polymerase activity. In addition reverse transcriptases catalyze the degradation of RNA in an RNA-DNA hybrid. The exonucleolytic activity proceeds in a 5' ---> 3' direction. The RNA or DNA directed activity requires a template (RNA or DNA) and a primer. The following is a schematic illustration of the reaction:Unit definition: One unit incorporates 1 nanomole of tritiated dTMP into acid insoluble productsusing poly(A)•oligo(dT) 12-18 as the template-primer in 20 minutes at 37° C.ApplicationsHIV reverse transcriptase is used for research on the AIDS primer. However it can be substituted for AMV reverse transcriptase, which is mainly used to transcribe mRNA into double stranded cDNA, that can be inserted into prokaryotic vectors. The enzyme can also be used with either single stranded DNA or RNA templates to make probes for use in hybridization experiments. It can be used for labeling the termini of DNA fragments with protruding 5' termini. The enzyme can also be used to sequence DNAs by the dideoxy chain termination method of Sanger when the Klenow fragment of E. coli DNA polymerase I, or the T7 DNA polymerase yield unsatisfactory results.Reagents0.05 M Tris, pH 8.3, containing 0.008 M MgCl21 mg/ml polyadenylic acid in water (poly A)DNA primer:Oligo d(T)12-181 µ mole dTTP/mL stock solution[methyl-3H]-Thymidine 5'-triphosphate (3H-dTTP)dTTP-3H-dTTP working mix: Add 1-2 µL 3H-dTTP per mL of 100 nmol/mL dTTP in order to obtain 1 to 1.5 x 105 cpm/mL1% bovine serum albumin10% perchloric acid1% perchloric acidBuffer substrate reaction mixture: Prepare fresh, immediately before use:For each 1mL of reaction mixture required mix:0.7 mL Tris/HCl, pH 8.3, 0.008M MgCl20.3 mL 1 mg/mL poly(A) RNA template0.005 mL 0.02 mg/mL oligo d(T)12-18 DNA primer0.02mL 1% BSAEnzymedilute as needed wtih 0.05M Tris/HCl, pH 8.3, 0.008M MgCl2 containing 0.1 mg/mL (1%) BSAProcedurePipette into each tube as follows:Buffer substrate mix：0.1 mLdTTP-3H3-dTTP：0.1 mLEnzyme：5-10 µLIncubate 20 minutes at 37° C. Stop reaction by adding 1 ml 10% cold perchloric acid. Filter through 0.2µ manifold filters used with Millipore vacuum manifold. Wash four times using 2mL 1% cold perchloric acid/wash. Transfer filter to scintillation vials. Add 2mL Cellosolve (or 2-methoxyethanol) to dissolve filter. Filters become opaque upon addition of Cellosolve. Make sure filters are dissolved before proceeding. Add 10mL scintillation cocktail and count.Calculation... Read More | Purity>97% SDS-PAGE.FunctionReceptor for interleukin-2 |