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Prospec/Leptin-A Tilapia/Leptin-A Tilapia Recombinant/1mg/CYT-1109-1mg-1mg
Cataloguenumber
CYT-1109
Introduction
Leptinisaproteinhormone.ItismainlyproducedinADIposecellsthatregulateenergyhomeostasisbyrestraininghunger.Leptintiestonuclearreceptorsinthehypothalamus(arcuatenucleus).SimilartoinsulinresistanceintypeIIdiabetes,inobesitythereisadecreaseinthesensitivitytowardsleptin,endinginafailuretoidentifysatiety,eveninhighlevelsofenergystoresorleptinitself.Full-lengthCDNAencoding2leptinsequences(tLepAandtLepB)and1leptinreceptorsequence(tLepR)existsintilapia(Oreochromisniloticus).Thefull-lengthcDNAoftLepRis3423bp,encodingaproteinof1140aminoacidwhichcontainedallfunctionallyimportantdomainsconservedamongvertebrateleptinreceptors.ThecDNAsoftLepAandtLepBare486bpand459bpinlength,encodingproteinsof161aaand152aa,respectively.Thethree-dimensionalstructuresoftLepAandtLepBdemonstratesstrongconservationoftertiarystructurewiththatofhumanleptincomprisedof4helixes.
Description
Leptin-ATilapiaRecombinantproducedinE.Coliisasingle,non-glycosylatedpolypeptidechaincontaining161aminoacidsandhavingamolecularmassof16,491Dalton.
TheLeptin-ATilapiaispurifiedbyproprietarychromatographictechniques.
Source
PhysicalAppearance
Formulation
Lyophilizedfromaconcentrated(1mg/ml)solutioncontainingNaHCO3at1:2salt:proteinratio.
Solubility
ItisrecommendedtoreconstitutethelyophilizedLeptin-ATilapiainsterilewateror0.4%NaHCO3adjustedtopH8-9,notlessthan100µg/ml,whichcanthenbefurtherdilutedtootheraqueoussolutions.
StABIlity
LyophilizedLeptin-ATilapiaalthoughstableatroomtemperaturefor3weeks,shouldbestoreddesiccatedbelow-18°C.UponreconstitutionLeptin-ATilapiashouldbestoredat4°Cbetween2-7daysandforfutureusebelow-18°C.Forlongtermstorageitisrecommendedtoaddacarrierprotein(0.1%HSAorBSA).Pleasepreventfreeze-thawcycles.
Purity
Greaterthan95.0%asdeterminedby:(a)Gelfiltrationanalysis.(b)AnalysisbySDS-PAGE.
Aminoacidsequence
ThefirstsixN-terminalaminoacidsofrecombinantTilapialeptinAareAla-Pro-Leu-Pro-Val-Glu.
BIOLOGicalActivity
TilapialeptinswerefoundtobebiologicallyactiveinpromotingproliferationofBAF/3cellsstablytransfectedwiththelongformofhumanleptinreceptor,buttheiractivitywaslowerthanthatofmammalianleptin.FurThermore,theTilapialeptinswerebiologicallyactiveinpromotingSTAT‐LUCactivationinCOS7cellstransfectedwithTilapialeptinreceptorbutnotincellstransfectedwithhumanleptinreceptor.TilapiaLeptinAwasmoreactivethanTilapiaLeptinB.
Proteincontent
ProteinquantitationwascarriedoutbyUVspectroscopyat280nmusingtheabsorbencyvalueof1.33for1mg/mlLeptin-ATilapiaastheextinctioncoefficientfora0.1%(1mg/ml)solutionatpH8.0.ThisvalueiscalculatedbytheDNAmancomputeranalysisprogramofproteinsequences.
SafetyDataSheet
SDS
