The transgene consists of 2xcHS4(chicken b-globin insulator)-ROSA26 promoter-splicing acceptor-CreN59-nMag-Nuclear localization signal-2PA-Nuclear localization signal-pMag-CreC60-poly A sequence-2xcHS4r(chicken b-globin insulator). The nMag and pMag are part of Magnets protein derived from the fragments of photoreceptor gene product Vivid (VVD) from a filamentous fungi Neurospora crassa. This transgene contains photo-switchable magnet proteins which can reassemble split Cre proteins by light-induced dimerization when exposed to blue light. Four of the six founder lines showed light-dependent Cre-mediated DNA recombination and line 2 was established.