This protocol describes the transcriptional profiling of E. coli cultures using microarrays. The protocol utilises RNA isolated as described in another SOP (SUMO RNA isolation from E. coli) and with hybridisation to Ocimum Ocichip E. coli K-12 microarrays.
We routinely select specific RNAi gene targets (400–600 bp) and primers using the RNAit software http://trypanofan.path.cam.ac.uk/software/RNAit.html. A single pair of PCR primers are designed that incorporate four selected restriction sites (not present in the RNAi target fragment) such that a single PCR product can be differentially digested and sequentially cloned. For example, using MCS1/2, the following primers could be used to clone antisense followed by sense fragments: Primer 1, XbaI–BamHI-5′ ...
Written Standard Operating Procedures provide workers with the operational information necessary to perform a job properly and ensure consistency in the operations. Standard Operating Procedures provide a historical record of steps in the how, why and when and serve as a training tool for teaching users.