PCR aspC1 pTargRev pTargetF pcrpdt
Digest pcrpdt SpeI 1 spedig
Ligate spedig lig
Transform lig Mach1 Spec pTarget-aspC1
Then, to the cells:
dsdna donor 500 bp flanking aspC1, and none of it
Grow Mach1/pCas Kan 30 colony
Grow colony Kan ara 30 pCas* λ-Red on · Cas9 was already there
Transform pCas* pTarget-aspC1 donor shocked donor is the repair template
Grow shocked 30 edited no selection — the edit happens here
Grow edited Spec Kan 30 picked selects the plasmid, not the edit
Grow picked Kan IPTG 30 cured pTarget cuts itself
Grow cured 42°C Mach1 ΔaspC1
We talked last time about this Jiang CRISPR procedure, and we discussed producing the plasmid the experiment needs. That part is cloning, and the construction file says it completely. What comes after is not cloning, and you cannot express it in those terms. The cloning steps were specifically about building a DNA. This is something different, and understanding it means considering everything going on inside the cell: transcription, translation, an inducer binding, which proteins are present and which are not, and what the cell was doing before you arrived. So to describe any of this, we have to talk about the cells themselves. That is the rest of today.
The CRISPR construction file from the end of the last lecture: the guide plasmid built by inverse PCR on pTargetF, digested with SpeI, ligated and transformed into Mach1 on spectinomycin to give pTarget-aspC1. The donor is not built here; it appears with the cell steps, because no cloning step consumes it.