Figure 4.

Northern hybridizations of TART^vir and TART^ame. Autoradiograph of total RNA from D. virilis and D . americana probed with the Pol coding region of the homologous TART. Both TART^vir probes detect several bands of RNA in the range of 6–9.5 kb. Sense and antisense RNAs do not migrate at exactly the same position, possibly because of differences in size or differences in conformation of the strands, which differ significantly in base composition. The exposure for the TART^vir sense-strand blot was equivalent to four times that of the antisense blot. Only the antisense blot of TART^ame is shown because we have been unable to detect sense-strand RNA for this element.