Oligonucleotides that inhibit the expression of the protein OB-RGRP, and method for detecting compounds that modify the interaction between the proteins of the OB-RGRP family and the leptin receptor

摘要

Oligonucleotides (ON), optionally modified and comprising 8-50 nucleotides (nt), that hybridize specifically to a 648 base pair (bp) sequence (1), given in the specification, and that inhibit expression of the leptin receptor related protein (OB-RGRP), are new. Independent claims are also included for the following: (1) interfering RNA (iRNA) of 15-25 nt that hybridize specifically with a 1114 bp sequence (21), reproduced, and inhibit expression of OB-RGRP; (2) vector that expresses ON or iRNA; (3) cell containing the vector of (2); (4) pharmaceutical composition containing ON, iRNA, the vector of (2) or the cell of (3); (5) fusion protein (FP) comprising a sequence with at least 65% identify with sequences (4) or (16), both of 131 amino acids (aa), or a substantial part of them, and a protein that is a donor or acceptor of energy, or a substantial part of it; (6) nucleic acid (I) that encodes FP; (7) nucleic acid with at least 65% identity with (I) or that hybridizes to it under stringent conditions; (8) cells that contain (I), or express FP, also their fragments, lysates and membranes; (9) methods for determining modified interaction between (4) or (13), or their homologs with at least 65% identity, and the leptin receptor; and (10) method for screening or detecting compounds that can be used to prevent or treat leptin-related disorders. ACTIVITY : Osteopathic; Anorectic; Antidiabetic; Cytostatic; Antiinflammatory; Immunomodulatory; Anabolic; Endocrine-Gen.; Antianemic; Antiangiogenic. MECHANISM OF ACTION : Inhibiting expression of OB-RGRP. HeLa cells were transformed with a vector that expressed the leptin receptor (OB-R) and a reporter gene (STAT3) and with an antisense agent, AS14, directed specifically against the OB-R related protein 3'-(triethylene glycol)-TGtAcAcGtGtAcGCcGtAa (AS14) (upper case indicates phosphorothioate; the five bases at each end are 2'-O-methylated). In absence of AS14, STAT3 activity was increased by 50% in presence of leptin, but in presence of AS14, leptin almost doubled STAT3 activity.