简介:Fromthepress-residueofthefreshroottuberofTrichosantheskirilowiiMaxim(Cu-curbitaceae),anewribosome-inactivatingprotein(RIP),trichobitacin,wasisolated.IthastheactivityofRNAN-glycosidaseandcaninhibitthegrowthofhumanplacentaltrophoblasticcells.Itsmolecularweightis27,228Da(ES-MS)andpI9.6.ItisasinglechainbasicRIP.Itsaminoacidcompositionwasdetermined.ItisanewRIP.Itconsistsof0.7~0.9%galactoseandmaybeaglycoprotein.ItsA’-andC-terminalaminoacidisAspandAla,respectively.ItsN-terminalpreliminaryaminoacidsequencehasbeendetermined.
简介:Thecompleteaminoacidsequenceofβ-momorcharin,aribosome-inactivatingproteinfromtheseedsofMomordicacharantiaLinn(Cucurbitaceae)hasbeendetermined.Thishasbeendonebythesequenceanalysisofpeptidesobtainedbyenzymaticdigestionwithtrypsin,chymotrypsinandS.aureusV8protease,aswellasbychemicalcleavagewithBNPS-skatole.Theproteinconsistsof249aminoacidresiduescontainingoneasparagine-linkedsugargroupattachedtothesiteofAsn51andhasacalculatedrelativemolecularmassof28,452Dawithoutadditionofthecarbohydrate.Comparisonofthissequencewiththoseoftrichosanthinandotherribosome-inactivatingproteinsfromdifferentspeciesofplantsshowsasignificanthomologywitheachother.Regardingthesimilarityoftheirbiologicalproperties,anactivedomainoftheseproteinshasbeenpredictedhere.
简介:VariableChargeX/Y(VCX/Y)isahumantestis-specificgenefamilythatlocalizedonXandYchromo-somes.Inthisstudy,VCYproteinwasexpressedinE.coliintheformofglutathione-S-transferase(GST)fusionprotein.Withthepurifiedfusionproteinasantigen,theanti-GST-VCYantibodywasgeneratedandthelocalizationofVCYproteininhumantestiswasdeterminedbyimmunohistochemistry.Inthetestisseminiferousepithelium,VCYproteinswerehighlyexpressedinnucleiofgermcells.Usingpropidiumio-didestainingandgreenfluorescentprotein(GFP)tagtechnologies,VCYandVCX-8rproteinsweremainlylocalizedinthenucleoliofCOS7cells.Inaddition,thecolocalizationforVCYandVCX-8rinCOS7cellswasalsoobserved.WithVCYcDNAasbait,acDNAfragmentofacidicribosomalproteinPOwasobtainedusingyeasttwo-hybridsystem.AlltheinformationaboveindicatesthatVCX/Yproteinfamilymightbeinvolvedintheregulationofribosomeassemblyduringspermatogenesis.