Isolation of specific messenger RNA by adsorption of polysomes to matrix-bound antibody

A procedure is presented for the purification of specific mRNAs, which exploits the ability of antibodies prepared against a native protein to bind to the nascent polypeptide on the polysome. Rather than precipitating these soluble antibody-polysome complexes with anti-antibody, which can lead to nonspecific trapping of polysomes, we have linked the anti-antibody to an insoluble matrix. Thus, the antibody-polysome complex binds to the anti-antibody support and nonspecific polysomes can easily be removed by several washes. We have found para-aminobenzyl cellulose (PAB cellulose), to be a suitable matrix for this purpose. This support can bind large quantities of anti-antibody and it displayed no detectable nonspecific affinity for polysomes or RNA. Using this procedure, we have obtained an apparently homogeneous preparation of ovalbumin mRNA.