Gt(ROSA)26Sor^{tm3(RNAi:Map2k1,Map2k2)Rkuhn}

Recombinase mediated cassette exchange (RMCE) was used to generate an allele where upon expression of Cre recombinase a knockdown RNAi is generated to a conserved region shared by Map2k1 and Map2k2 mRNA that has 100% homology. A short hairpin RNA was designed with a loxP-flanked stop cassette in the loop portion of the RNAi between the sense and anti-sense sequences. The RNAi was put under the control of human U6 promoter and the entire cassette was placed downstream of a splice acceptor and a frt-flanked neomycin resistance gene. RMCE was then performed on ES cells containing the Gt(ROSA)26tm1Rkuhn allele. When cre recombinase was expressed in nervous tissue, protein levels of Map2k1 were reduced by 65% and Map2k2 by 50%. (J:133638)