The N-terminal fragment of cre recombinase (aa 19-59) fused to the intein-N peptide fragment (123 N terminal amino acids of the DnaE split intein sequence was cloned into a vector containing the human enhancer 611 sequence (hs611) and an Hsp68 minimal promoter and lacZ reporter. The final construct included an IRES sequence separating the lacZ gene and Ncre-intein-N. Injection of the linearized construct into pronuclei was performed to generated transgenic founders. Line numbers were not identified in the publication.