id author title date pages extension mime words sentences flesch summary cache txt cord-283998-whwksoxt Tannock, Gregory A. The RNA of human coronavirus OC-43 1977-12-31 .txt text/plain 3978 213 57 Abstract A homogeneous RNA complex with a sedimentation coefficient of 70 S and an apparent molecular weight of approximately 6.1 × 106 was released from purified 32P-labeled, mouse-brain-derived OC-43 virus after treatment with 1% sodium dodecyl sulfate (SDS) for 15 min at 23°. This suggests that (a) extensive nicking of a large RNA molecule has occurred during viral growth, due to ribonucleases which are inactivated during phenol extractions; (b) heterogeneity for OC-43 RNA is not due to internal ribonuclease activity and fragments are held together by noncovalent linkages much weaker than those present in the 70 S retroviral RNA complex, or by small proteins; or, most probably, (c) a combination of extensive nicking and weak noncovalent linkages results in the heterogeneous denaturation products. The RNA of avian infectious bronchitis virus (IBV) was first described by Tannock (1973) , who obtained from purified virions a highly heterogeneous array of RNA fragments using a phenol-sodium dodecyl sulfate (SDS) extraction procedure. ./cache/cord-283998-whwksoxt.txt ./txt/cord-283998-whwksoxt.txt