The MDM2 oncoprotein binds specifically to RNA through its RING finger domain.

摘要: The cellular mdm2 gene has transforming activity when overexpressed and is amplified in a variety of human tumors. At least part the ability MDM2 protein due to binding inactivating p53 tumor suppressor protein. Additionally, this forms complex vivo with L5 ribosomal its associated 5S RNA may be complex. A homopolymer assay SELEX procedure have been used characterize RNA-binding MDM2. binds efficiently homopolyribonucleotide poly(G) but not other homopolyribonucleotides. This independent interaction protein, which occurs through central acidic domain An was performed identify specific ligands that bind high affinity (HDM2) After 10 rounds selection amplification, subset molecules bound HDM2 isolated from randomized pool. Sequencing these selected revealed small number sequence motifs were selected. RING finger Furthermore, single amino acid substitution domain, G446S, completely abolishes binding. These observations, showing L5/5S ribonucleoprotein particle can also sequences or structures, suggest role for translational regulation cell.