The constitutive decay element (CDE) in the 3' UTR was targeted with gRNAs (targeting TGTCCTGGAGGACCCAGTGT and GGAGCTGAGCTGTCCCCACC) using CRISPR/Cas9 technology, resulting in a 71 bp deletion (AGGACCCAGTGTGGGAAGCTGTCTTCAGACAGACATGTTTTCTGTGAAAACGGAGCTGAGCTGTCCCCACC). (J:306876)