The Zn-finger domain of RIZ protein promotes MCF-7 cell proliferation.
In order to understand the oncogenic properties of retinoblastoma-interacting zinc-finger (RIZ) gene products, we produced an MCF-7-derived cell line expressing a fusion protein containing the zinc-finger (aa 359-497) domain of RIZ protein (MCF-7/znf). The Zn-finger domain contains three of the eight putative Zn-finger motifs and is located in proximity of the E1A-like domain containing the Rb protein-binding motif. The MCF-7/znf cells showed a higher growth rate than the parental or the control cell lines, both in hormone-deprived conditions or upon estrogen stimulation. Furthermore, they were less sensitive to the growth inhibitory effect of anti-estrogens and showed a higher level of expression of cyclin D1 and A. The expressed Zn-finger domain recombinant product was localized in the nucleus and in the nucleoli and its expression modified the pattern of actin staining in the cytoplasm. In conclusion the presented results indicated that the Zn-finger domain could be endowed with the putative oncogenic activity of RIZ2 gene product.
Dipartimento di Patologia generale, Facoltà di Medicina e Chirurgia, Seconda Università degli studi di Napoli, Via Luigi de Crecchio, 7, Naples I-80138, Italy.
Mariangela
M
Rossi
Ciro
C
Abbondanza
Andrea
A
D'Arcangelo
Patrizia
P
Gazzerro
Nicola
N
Medici
Bruno
B
Moncharmont
Giovanni Alfredo
GA
Puca
D001943:Breast Neoplasms / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004268:DNA-Binding Proteins / Q000502:physiology*; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D009687:Nuclear Proteins / Q000502:physiology*; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014157:Transcription Factors / Q000502:physiology*; D014162:Transfection; D016335:Zinc Fingers / Q000502:physiology
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D011495:Histone-Lysine N-Methyltransferase; C093563:PRDM2 protein, human