Patent ID: 8822168

Claim:
An assay to detect presence, amount, and/or activity of a survival of motor neuron (SMN) complex in a cellular extract when said extract comprises an SMN complex, wherein said activity comprises small nuclear ribonucleoprotein particle (snRNP) assembly, said assay comprising: a) transcribing a nucleic acid molecule in vitro in the presence of a first label to generate a labeled full length small nuclear RNA (snRNA) molecule; b) contacting a substrate with said labeled full length snRNA molecule of step a), wherein said labeled full length snRNA specifically binds to said substrate via said label; c) contacting said labeled full length snRNA molecule of step b) with a cellular extract in the presence of adenosine triphosphate (ATP), wherein when said cellular extract comprises a SMN complex, a SMN protein, and Sm proteins comprising B/B′, D1, D2, D3, E, F, and G, said Sm proteins bind to said labeled full length snRNA molecule to formulate a complex, an assembled snRNP, comprising said labeled full length snRNA molecule and said Sm proteins; d) contacting said complex comprising said labeled full length snRNA molecule and said Sm proteins with a first antibody that specifically binds a RNA binding Sm protein that binds snRNA under stringent conditions in a buffered contacting composition comprising high salt and heparin such that the first antibody binds a snRNA binding Sm protein present in the assembled snRNP in order to determine an amount of Sm proteins that assemble on the snRNA molecule; e) contacting said first antibody with a second antibody that specifically binds said first antibody; and f) detecting an amount of said second antibody specifically bound to said first antibody, wherein the amount of bound second antibody is indicative of the amount of Sm protein in the assembled snRNP and the amount of Sm protein in the assembled snRNP is indicative of the presence, amount, and/or activity of the SMN complex in the extract, wherein, steps b) to f) are performed on the substrate of step b).