No signal on Northern blot - (Dec/02/2004 )
Before prehybridization, I stained the membrane with methylene blue and the 28s and 18s rRNA was very clear. However, after hybridization and detection, there was no signal on the membrane. To analyse the possible reason, I stained the membrane again with methylene blue. To my surprise, there was no band. I dont' know if the RNA was degradated or stripped during the course of washing or hybridization.
Anyone can give some help?
i suggest you run two gels at the same time. one is used for staining to evaulate your RNA quality. the other one is used for NORTHERN BLOT. can you assure that your staining soluton is RNase free? i never stain my RNA gel when i did northern blot.