The following elements were inserted in an intron of the gene: a loxP site, a neomycin resistance gene and STOP cassette, a second loxP site, sequence coding for an HA tag in-frame with the coding sequence for Mib1 with a p.V943F mutation, IRES sequence and the EGFP fluorescent reporter gene. The inserted Mib1 and EGFP genes will only be expressed after Cre-mediated removal of the neo-STOP cassette.