The RMCE cassette of the TI{CRIMIC.TG4.0}Arpc3ACR60123-TG4.0 insertion has been replaced with a TI{FFL.0} cassette that is in gene-trap (GT) orientation relative to Arpc3A. This is expected to truncate the Arpc3A protein and to result in the expression of a separate mCherry protein under the control of endogenous Arpc3A regulatory sequences.