简介：Translationinitiationsites(TISs)areimportantsignalsincDNAsequences.InmanypreviousattemptstopredictTISsincDNAsequences,threemajorfactorsaffectthepredictionperformance:thenatureofthecDNAsequencesets,therelevantfeaturesselected,andtheclassificationmethodsused.Inthispaper,weexaminedifferentapproachestoselectandintegraterelevantfeaturesforTISprediction.Thetopselectedsignificantfeaturesincludethefeaturesfromthepositionweightmatrixandthepropensitymatrix,thenumberofnucleotideCinthesequencedownstreamATG,thenumberofdownstreamstopcodons,thenumberofupstreamATGs,andthenumberofsomeaminoacids,suchasaminoacidsAandD.Withthenumericaldatageneratedfromthesefeatures,differentclassificationmethods,includingdecisiontree,naiveBayes,andsupportvectormachine,wereappliedtothreeindependentsequencesets.Theidentifiedsignificantfeatureswerefoundtobebiologicallymeaningful,whiletheexperimentsshowedpromisingresults.

简介：One-cellmouseembryosfromKMstrainandB6C3F1strainwereculturedinM16medium,inwhich2-cellblockgenerallyoccurs.EmbryosofKMstrainexhibited2-cellblock,whereasB6C3F1embryos,whichareregardedasanonblockingstrain,proceededtothe4-cellstageinourculturecondition.Itisoftenassumedthattheblockofearlydevelopmentisduetothefailureofzygoticgeneactivation(ZGA)inculturedembryos.Inthisstudyweexaminedproteinsynthesispatternsbytwo-dimensionalgelelectrophoresisof[35S]methionineradiolabeled2-cellembryos.Embryosfromtheblockingstrainandthenonblockingstrainwerecomparedintheirdevelopmentbothinvitroandinvivo.ThedetectionofTRCexpression,amarkerofZGA,at42hposthCGinKMembryosdevelopedinvitrosuggestedthatZGAwasalsoinitiatedeveninthe2-cellarrestedembryos.Nevertheless,asignificantdelayofZGAwasobservedinKMstrainascomparedwithnormallydevelopedB6C3F1embryos.AttheverybeginningofmajorZGAasearlyas36hposthCG,TRChasalreadybeenexpressedinB6C3F1embryosdevelopedinvitroandKMembryosdevelopedinvivo.Butfor2-cellblockedKMembryos,TRCwasstillnotdetectableevenat38hposthCG.Theseevidencessuggestthat2-cell-blockedembryosdoinitiateZGA,andthat2-cellblockphenomenonisduenottothedisabilityininitiatingZGA,buttoadelayofZGA.