Heterogeneous nuclear Ribonucleic Acid (HnRNA)

The hnRNA is the collective term for the unprocessed mRNA (pre-mRNA) molecules in the nucleus. It is largely comprised of the pre-mRNA molecules ... SkiptocontentMainNavigationSearchDictionaryArticlesTutorialsBiologyForumDefinitionnoun,plural:hnRNAsTheabbreviatedformforheterogeneousnuclearribonucleicacid:anextrachromosomalRNAmoleculeinthenucleusthatserveasprimarytranscriptfromDNASupplementThehnRNAisthecollectivetermfortheunprocessedmRNA(pre-mRNA)moleculesinthenucleus.Itislargelycomprisedofthepre-mRNAmoleculesthatrequireextensiveprocessingtobecomematuremRNAmolecules.ThehnRNAthatisassociatedwithproteinsformtheheterogenousnuclearribonucleoprotein(hnRNP).TheinitialstepofsynthesizingmRNAistranscription.Duringtranscription,theDNAsequenceisreadbyRNApolymeraseinorderforthelattertocreateacomplementary,antiparallelRNAstrand(calledprimarytranscript).TheprimarytranscriptthatlaterbecomesamessengerRNA(mRNA)isreferredtoasapre-mRNA.Thepre-mRNA,inturn,needstoundergofurtherprocessingtobecomeafunctionalmaturemRNA.Apre-mRNAmoleculebecomesamaturemRNAmoleculeafterhavingundergonethefollowingprocesses:5′capaddition–theadditionofa5’captothefrontor5′endofthepre-mRNAmoleculeatthestartoftranscriptionsplicing–removalofanyintrons(non-codingsequences)andthesplicingtogetherofexons(protein-codingsequences)editing–insomeinstances,thenucleotidecompositionisalteredpolyadenylation–apolyatailisaddedtothefree3′endatthecleavagesiteOncetheseprocessesarecompletedthematuremRNAcanthenbetransportedfromthenucleusintothecytoplasmforproteintranslation.AlthoughthehnRNAserveassourceofmRNA,notallhnRNAbecomecytoplasmicmRNA.Seealso:pre-mRNALastupdatedonOctober12th,2020Youwillalsolike...WaterinPlantsThemovementofmolecules(specifically,waterandsolutes)isvitaltotheunderstandingofplantprocesses.Thistuto..StemsStemsprimarilyprovideplantsstructuralsupport.Thistutorialincludeslecturesontheexternalformofawoodytwig..VascularPlants:FernsandRelativesFernsandtheirrelativesarevascularplants,meaningtheyhavexylemandphloemtissues.Becauseofthepresenceofva..DNAStructure&DNAReplicationDNAisadoublehelixstructurecomprisedofnucleotides.Anucleotide,inturn,ismadeupofphosphatemolecule,deoxy..CommunityPatternsLearnaboutcommunitypatternsandtheecologicalfactorsinfluencingthesepatterns.Revisitsomeoftheecosystemsyou..ExamplesofNaturalSelectionDarwin'sFinchesareanexampleofnaturalselectioninaction.Theyareanexcellentexampleofthewayspecies'genep..RelatedArticles...NorelatedarticlesfoundSeeallRelatedTopics