Note to self: verify Cre-line before using

I received an email the other day suggesting that some AAV-based DREADDs were not working 'as advertised'.

To make a long email saga short it turns out that the Cre-driver line used had not been validated in the particular tissue being used.

Thus the reason the DREADD was not being expressed is because there was no expression of Cre in the cells of interest.

Here's what my lab does (and what we recommend) before using a Cre-line:

  • Check the literature for expression in the tissue/cell type of interest
  • Check the literature to see if any lab has ever used it to express a FLEX/DIO-based cargo in the cell type of interest
  • If the controls do not work this would indicate:
    • The Cre-line does not express sufficient Cre in the cell of interest
    • There is something wrong with your technique
Only after you have validated the Cre-line (or are sure it has been validated by others in the particular cell type you are using) should you attempt to express opto- or chemogenetic-based cargos.


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