摘要
ThesplicingofmanyalternativeexonsintheprecursormessengerRNA(pre-mRNA)isregulatedbyextracellularfactorsbuttheunderlyingmolecularbasesremainunclear.HerewereportthedifferentialregulationofBcl-xpre-mRNAsplicingbyextracellularfactorsandtheirdistinctrequirementsforpre-mRNAelements.InK562leukemiacells,treatmentwithinterleukin-6(IL-6)orgranulocyte-macrophagecolonystimulatingfactor(GM-CSF)reducedtheproportionoftheBcl-xLvariantmRNAwhiletreatmentwith12-O-tetradecanoylphorbol13-acetate(TPA)hadnoeffect.InU251gliomacells,however,TPAefficientlyincreasedtheBcl-xLlevel.Theseregulationswerealsoseenforatransfectedsplicingreportermini-gene.Furtheranalysesofdeletionmutantsindicatethatnucleotides1-176ofthedownstreamintronarerequiredfortheIL-6effect,whereasadditionalnucleotides177-284areessentialfortheGM-CSFeffect.AsfortheTPAeffect,onlynucleotides1-76arerequiredinthedownstreamintron.Thus,IL-6,GM-CSFandTPAdifferentiallyregulateBcl-xsplicingandrequirespecificintronicpre-mRNAsequencesfortheirrespectiveeffects.
出版日期
2004年06月16日(中国Betway体育网页登陆平台首次上网日期,不代表论文的发表时间)