Figure 2.

(A) Southern blot with EcoRI-digested DNAs prepared from littermate animals derived from a chimeric rhodopsin knockout founder. +/+, −/−, and +/− designate wild-type, homozygous, and hemizygous mice, respectively. +/+ mice exhibit a 5.1-kb band indicative of genomic opsin DNA. −/− mice exhibit a 6.5-kb band indicative of the targeted gene. +/− mice exhibit both. (B) Reverse transcription–PCR. RNA prepared from retinas of 30-day-old +/+ or +/− mice were reverse transcribed and amplified with primers specific for rod T_α or rod opsin. Primer pairs spanned an intron. Although T_α mRNA was detected, no opsin mRNA was detected in −/− retinas. Transducin PCR products were 370 bp and 846 bp for RNA and DNA, respectively. Opsin PCR products were 397 bp and 513 bp for RNA and DNA, respectively. G represents amplified genomic DNA. (C) Western blot probed with rhodopsin-specific Ret-P1 antibody. Equivalent amounts of retinal homogenate were loaded in the first three lanes (left to right); 50-fold more homogenate was loaded in the far right lane.