REOVIRUS M2 GENE IS ASSOCIATED WITH CHROMIUM RELEASE FROM MOUSE L-CELLS

In this study, we investigated the interaction of reovirus particles w ith cell membranes by using a Cr-51 release assay. We confirmed prior observations (J. Borsa, B. D. Morash, M. D. Sargent, T. P. Copps, P. A . Lievaart, and J. G. Szekely, J. Gen. Virol. 45:161-170, 1979) that i ntermediate subviral particles (ISVPs) of reovirus type 3 strain Abney (T3A) induced the release of Cr-51 from preloaded L cells and showed that the intact virion and core forms did not. Reovirus type 1 strain Lang (T1L) ISVPs were found to be less efficient at Cr-51 release than T3A ISVPs. Reassortants between these strains indicated that the Cr-5 1 release phenotype segregates with the M2 gene segment. Biochemical s tudies indicated that the ISVPs' acquisition of the capacity to induce Cr-51 release followed the cleavage of the viral M2 gene product mu1/ mu1C to fragments delta and psi during virion conversion to ISVP but d id not directly correlate with this cleavage. These studies suggest th at the reovirus M2 gene product (in its cleaved form) plays a role in interacting with cell membranes.