
Fig. 1. Transcript levels for V-ATPase subunits from Manduca sexta during
starvation. (A) Pooled total RNA from the midgut of three fifth-instar larvae
(2 µg each) was separated by gel electrophoresis, transferred onto nylon
membranes and hybridized with digoxigenin-labelled ssRNA probes specific for
the indicated V-ATPase subunits. Labelled transcripts from starved (left) or
feeding (right) larvae were visualized by chemiluminescence and
autoradiography. The far left column shows molecular mass standards (in kb).
(B) Pooled total RNA was dotted onto nitrocellulose and hybridized, and
chemiluminescence signals were quantified densitometrically. Values (±
S.E.M., N=3) are given as a percentage of signal intensities obtained
from feeding larvae and are normalized to the transcript levels of ribosomal
protein S7 (Jiang et al.,
1996). Representative dots have been inserted in the corresponding
columns with RNA from feeding larvae in the upper row and RNA from starved
larvae in the lower row. AH, subunits of the V1 complex;
ae, subunits of the Vo complex.