A yeast two-hybrid screen identifies histone H2A.Z as a transcription factor ZNF24 interactor
ABSTRACT ZNF24 is a pleiotropic factor that has a role in transcription regulation, hematopoiesis, brain development, and cancers, but the molecular mechanisms underlying its functions are not clearly understood. In this study, histone variant H2A.Z has been identified in yeast-two-hybrid assays with ZNF24 as bait. GST pull-down, co-immunoprecipitation and co-localization assays confirm the interaction between ZNF24 and H2A.Z. H2A.Z has been implicated in many diverse biological processes. High expression of H2A.Z is ubiquitously detected in the progression of breast cancer, and is significantly associated with lymph node metastasis and patient survival. Thus, our results provide important information for the molecular mechanisms of ZNF24 functions and suggest that ZNF24 may be is implicated in transcriptional regulation of genes associated with oncogenesis by interaction with H2A.Z. J. Cell. Biochem. 113: 3411-3418, 2012. © 2012 Wiley Periodicals, Inc.
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ABSTRACT: ZNF24 is a member of the SCAN domain family of Krüppel-like zinc finger (ZF) transcription factors, which plays a critical role in cell proliferation and differentiation. However, how ZNF24 enters the nucleus in order to exert its function remains unclear since its nuclear localization signal(s) (NLS) has not been identified. Here, we generated a series of GFP-tagged deletion and point mutants and assessed their subcellular localization. Our results delimit the NLS to ZF1-2. Deletion of ZF1-2 caused cytoplasmic accumulation of ZNF24. Fusion of the ZF1-2 to green fluorescent protein (GFP) targeted GFP to the nucleus, demonstrating that the ZF1-2 is both necessary and sufficient for nuclear localization. ZNF24 containing histidine to leucine mutations that disrupt the structure of ZF1 or/and ZF2 retains appropriate nuclear localization, indicating that neither the tertiary structure of the zinc fingers nor specific DNA binding are necessary for nuclear localization. K286A and R290A mutation led to partial cytoplasmic accumulation. Co-immunoprecipitation demonstrated that ZNF24 interacted with importin-β and this interaction required the ZF motifs. The β-Catenin (CTNNB1) luciferase assays showed that the ZNF24 mutants defective in nuclear localization could not promote CTNNB1promoter activation as the wild-type ZNF24 did. Taken together, these results suggest that consecutive ZF1-2 is critical for the regulation of ZNF24 nuclear localization and its transactivation function.PLoS ONE 11/2013; 8(11):e79910. DOI:10.1371/journal.pone.0079910 · 3.53 Impact Factor