Functional role of post-translational modifications of Sp1 in tumorigenesis

Table 1 Post-translational modification of Sp1

PTM	Modified sites	Modified enzymes	Functions	Ref.
Phosphorylation	Ser59	CDK2	Increase Sp1 DNA binding activity	[21]
	Ser101	ATM	Involve in DNA damage and repair	[25]
	Ser131	DNA-PK	Upregulate expression of the HIV-1 Tat protein.	[26]
	Thr266	Ras-MAPK	Increase expression of apolipoprotein A-I	[27]
	Thr278/739	JNK1	Increase Sp1 protein stability	[28]
	Thr453/739	P42/p44 MAPK	Enhance VEGF expression	[29]
		ERK1/2	Repress PDGFR-α transcription	[30]
		ERK1/2	Inhibit RECK expression and promote cell invasion	[31]
	Ser641	PI3K/PKCζ	Increase luteinizing hormone receptor (LHR) transcription	[32]
	Thr668	CKII	Decreased Sp1 DNA binding acticity	[23]
	Thr668/Ser670/Thr681	PKCζ	Increase PDGF transcription	[24]
	Thr739	CDK1	Decrease Sp1 binding activity	[22]
Sumoylation	Lys16	Sumo-1	Enhance Sp1 degradation	[33, 34]
Methylation	ND	ND	Recruit Suv39H1 and HDAC1 to induce chromatin remodeling	[35]
Acetylation	Lys703	P300	Recruit HDAC1 and p300 to the promoter of the 12(S)-lipoxygenase	[36]
Glycosylation	Leu56/57	ND	Sp1 degradation	[37]
	Ser612/641/698/702, Thr640	ND	Regulate transcriptional activity of Sp1	[38]

ISSN: 1423-0127