CRISPR has the potential to cure many genetic diseases, but it’s notoriously hard to use in neurons. In this work we tackled 2 of the main hurdles: Cas9 delivery and DNA repair. And we discovered… The rules of genome editing are different in neurons👇🏾

Stay tuned for more exciting neuron editing work from @TheConklinLab! Extremely grateful to @BruceConklin for all the support

@dkjhaunc Could be! It does seem related to Cas9 scanning/interrogating DNA. Maybe R loops, exposing ssDNA, etc or could be disassembly as you point out

@dkjhaunc Yup! I think that’s why we see RRM2 inhibition decrease insertions and increase deletions. Inhibiting this unexpectedly increased nucleotide production

So we used drugs to inhibit RRM2 while editing. For 1 sgRNA, it gave us 50% more editing at an early timepoint! By tripling the rate of 1-base deletions specifically. ❗️Manipulating this unexpected DNA repair factor influenced both the efficiency & precision of neuron editing❗️

Many of these DNA repair genes upregulated by neurons were very unexpected. One of our top hits, RRM2, is usually expressed only during S phase of cell division! What’s it doing in a nondividing cell? And importantly, could it be affecting the outcome of our Cas9 edits?