BTG2isfoundtobeoneoftheimmediateearlygenesup-regulatedbyneuralgrowthfactor(NGF)andepidermalgrowthfactor(EGF).Itstranscriptionallevelisalsoup-regulatedbyp53,gammarADIation,adriamycinandUVtreatmentofcells.BTGseemstobeimportantforthecellcycleprogressionasBTG2ispreferentiallyexpressedinquiescentcells.Over-expressionofBTG2decreasesthegrowthofNIH3T3cellsandinducesneuronaldifferentiationandpreventionapoptosisofPC12cells.Molecularly,BTG2expressioninduceshypophosphorylationofRBandG1arrestwhichcouldberescuedbyoverexpressionofcyclinD1.BTG1andBTG2interactwithPRMT1(predominantcellulararginineN-methyltransferase)andincreasePRMT1methyltransferaseactivity.BoxCdomaininBTG1and2areresponsIBLefortheinteraction.BoxCdomainaloneactsasadominantnegativewhichblocksPRMT1activity.PRMT1activityisessentialforNGFinducedPC12differentiation,andblockingPRMT1byBoxCdomainofBTG1or2inducesapoptosis.Inaddition,BTG2andHoxB9interactionenhancesthetranscriptionofHoxb9.Lastly,associationofBTG2andBTG1withCaf1isalsoreportedtomodulatestranscriptionalactivityofCAF1.

Contributor:Yen-LiangChen,PhD

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