Comparison of native and KCl treated 40S ribosomal subunits from the silkmoth Antherea pernyi and mammals.

Native 40S ribosomal subunits and 18S ribosomal RNA from ovarian follicles of the silkmoth A. pernyi showed a lower sedimentation coefficient in comparison to ascites cells, in contrast to the KCl treated 40S ribosomal subunits where no difference was observed in both tissues. Moreover the silkmoth native 40S ribosomal subunits--in contrast to the KCl treated ones--could not reassociate with radioactive ascites cell 60S ribosomal subunits. These results, combined with the great similarities in the two dimensional electrophoretic patterns of 40S ribosomal proteins from silkmoth follicles and other mammalian cells lead to the possibility of the existence of a specific RNase associated with the 40S ribosomal subunit.