Novel CARM1-Interacting Protein, DZIP3, Is a Transcriptional Coactivator of Estrogen Receptor-α.
Coactivator-associated arginine methyltransferase 1 (CARM1) is known to promote estrogen receptor (ER)α-mediated transcription in breast cancer cells. To further characterize the regulation of ERα-mediated transcription by CARM1, we screened CARM1-interacting proteins by yeast two-hybrid. Here, we have identified an E3 ubiquitin ligase, DAZ (deleted in azoospermia)-interacting protein 3 (DZIP3), as a novel CARM1-binding protein. DZIP3-dependent ubiquitination of histone H2A has been associated with repression of transcription. However, ERα reporter gene assays demonstrated that DZIP3 enhanced ERα-mediated transcription and cooperated synergistically with CARM1. Interaction with CARM1 was observed with the E3 ligase RING domain of DZIP3. The methyltransferase activity of CARM1 partially contributed to the synergy with DZIP3 for transcription activation, but the E3 ubiquitin ligase activity of DZIP3 was dispensable. DZIP3 also interacted with the C-terminal activation domain 2 of glucocorticoid receptor-interacting protein 1 (GRIP1) and enhanced the interaction between GRIP1 and CARM1. Depletion of DZIP3 by small interfering RNA in MCF7 cells reduced estradiol-induced gene expression of ERα target genes, GREB1 and pS2, and DZIP3 was recruited to the estrogen response elements of the same ERα target genes. These results indicate that DZIP3 is a novel coactivator of ERα target gene expression.
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Daniel J
DJ
Purcell
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Swati
S
Chauhan
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Diane
D
Jimenez-Stinson
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Kathleen R
KR
Elliott
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Tenzin D
TD
Tsewang
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Young-Ho
YH
Lee
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
Brian
B
Marples
Section of Radiation Oncology (D.J.P., S.C., D.J.-S., K.R.E., T.D.T., D.Y.L.), Division of Hematology-Oncology, Department of Internal Medicine, and University of New Mexico Comprehensive Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131; Department of Biochemistry (Y.-H.L.), Keck School of Medicine, University of Southern California. Los Angeles, California 90089; and Department of Radiation Oncology (B.M.), William Beaumont Hospital, Royal Oak, Michigan 48073.
David Y
DY
Lee
D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D011484:Protein-Arginine N-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000235:genetics / Q000502:physiology; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*
D002352:Carrier Proteins; C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; C491310:GRIP1 protein, human; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; D011484:Protein-Arginine N-Methyltransferases; C119966:coactivator-associated arginine methyltransferase 1; C476989:DZIP3 protein, human; D044767:Ubiquitin-Protein Ligases