ZNF652, a novel zinc finger protein, interacts with the putative breast tumor suppressor CBFA2T3 to repress transcription.
The transcriptional repressor CBFA2T3 is a putative breast tumor suppressor. To define the role of CBFA2T3, we used a segment of this protein as bait in a yeast two-hybrid screen and identified a novel uncharacterized protein, ZNF652. In general, primary tumors and cancer cell lines showed lower expression of ZNF652 than normal tissues. Together with the location of this gene on the long arm of chromosome 17q, a region of frequent loss of heterozygosity in cancer, these results suggest a possible role of ZNF652 in tumorigenesis. In silico analysis of this protein revealed that it contains multiple classic zinc finger domains that are predicted to bind DNA. Coimmunoprecipitation assays showed that ZNF652 strongly interacts with CBFA2T3 and this interaction occurs through the COOH-terminal 109 amino acids of ZNF652. In contrast, there was a weak interaction of ZNF652 with CBFA2T1 and CBFA2T2, the other two members of this ETO family. Transcriptional reporter assays further confirmed the strength and selectivity of the ZNF652-CBFA2T3 interaction. The transcriptional repression of growth factor independent-1 (GFI-1), a previously characterized ETO effector zinc finger protein, was shown to be enhanced by CBFA2T1, but to a lesser extent by CBFA2T2 and CBFA2T3. We therefore suggest that each of the various gene effector zinc finger proteins may specifically interact with one or more of the ETO proteins to generate a defined range of transcriptional repressor complexes.
Kumar
Raman
R
Breast Cancer Genetics Group, Dame Roma Mitchell Cancer Research Laboratories, Hanson Institute, Institute of Medical and Veterinary Science, Frome Road, Adelaide, SA 5000, Australia.
Manning
Jantina
J
Spendlove
Hayley E
HE
Kremmidiotis
Gabriel
G
McKirdy
Ross
R
Lee
Jaclyn
J
Millband
David N
DN
Cheney
Kelly M
KM
Stampfer
Martha R
MR
Dwivedi
Prem P
PP
Morris
Howard A
HA
Callen
David F
DF
D000595:Amino Acid Sequence; D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D016147:Genes, Tumor Suppressor; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D000075142:RUNX1 Translocation Partner 1 Protein; D011817:Rabbits; D051381:Rats; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D016335:Zinc Fingers / Q000235:genetics / Q000502:physiology*
C110408:CBFA2T2 myeloid-transforming gene-related protein; C115744:CBFA2T3 protein, human; D004268:DNA-Binding Proteins; C498275:GFI1 protein, human; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D000075142:RUNX1 Translocation Partner 1 Protein; C082222:RUNX1T1 protein, human; D012097:Repressor Proteins; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins