RNA blot analysis of subunit A in A. thaliana. The probe utilized was approximately 1700 base pairs in length corresponding to the vacuolar type H+-ATPase subunit A cDNA from Arabidopsis thaliana. Probe DNA was labeled with digoxigenin via the Polymerase Chain Reaction. Each lane contained 20 μg of whole RNA. Lanes correspond to the following organs: S-seedlings, R-roots, L-leaves, B-bolts, Si-siliques, and F-flowers. EF-Tu is a nuclear encoded chloroplast gene transcribed in all organs of the plant. Hybridization to a digoxigenin labeled probe corresponding to EF-Tu was performed to evaluate the RNA isolated from each organ to determine its suitability for RNA blot analysis.