Coiled-coil domain of PML is essential for the aberrant dynamics of PML-RARalpha, resulting in sequestration and decreased mobility of SMRT.
Promyelocytic leukemia-retinoic acid receptor alpha (PML-RARalpha) is the most frequent RARalpha fusion protein in acute promyelocytic leukemia (APL). Our previous study has demonstrated that, compared with RARalpha, PML-RARalpha had reduced intranuclear mobility accompanied with mislocalization. To understand the molecular basis for the altered dynamics of PML-RARalpha fusion protein, we performed FRAP analysis at a single cell level. Results indicated that three known sumoylation site mutated PML-RARalpha had same intracellular localization and reduced mobility as wild-type counterpart. The coiled-coil domain of PML is responsible for the aberrant dynamics of PML-RARalpha. In addition, we revealed that co-repressor SMRT co-localized with PML-RARalpha, resulting in the immobilization of SMRT while ATRA treatment eliminated their association and reversed the immobile effect of SMRT. Furthermore, co-activator CBP, co-localized with PML-RARalpha in an ATRA-independent way, was demonstrated as a high dynamic intranuclear molecule. These results would shed new insights for the molecular mechanisms of PML-RARalpha-associated leukemogenesis.
Huang
Ying
Y
Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiaotong University School of Medicine (SJTU-SM), No. 280, Chong-Qing South Road, Shanghai 200025, China.
Qiu
Jihui
J
Chen
Guoqiang
G
Dong
Shuo
S
D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007668:Kidney / Q000737:chemistry* / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D056985:Nuclear Receptor Co-Repressor 2; D000071156:Promyelocytic Leukemia Protein; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000502:physiology; D018168:Receptors, Retinoic Acid / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D000072482:Retinoic Acid Receptor alpha; D013329:Structure-Activity Relationship; D014157:Transcription Factors / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000378:metabolism*
D004268:DNA-Binding Proteins; C539130:NCOR2 protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D056985:Nuclear Receptor Co-Repressor 2; D000071156:Promyelocytic Leukemia Protein; C000607071:RARA protein, human; D018168:Receptors, Retinoic Acid; D012097:Repressor Proteins; D000072482:Retinoic Acid Receptor alpha; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human