The p65(AD)::Zip+ entry in FlyBase represents a hemidriver that contains the transcriptional activation domain from the Homo sapiens 'p65' gene (RELA, HGNC:9955) fused to the Zip+ heterodimerizing leucine zipper (the EE[]RR[]L zipper from PMID:11344333). The exact sequence of the hemidriver may differ depending on the particular transgene or modified endogenous locus being used. For example, while a nuclear localization signal must be present in the hemidriver, its origin may vary. p65(AD)::Zip+ forms one half of a 'split driver' system: when combined in vivo with a hemidriver containing a DNA-binding domain fused to the Zip- heterodimerizing leucine zipper (the RR[]EE[]L zipper from PMID:11344333), the interaction between the Zip+/Zip- heterodimerizing pair can reconstitute a functional transcriptional activator that can drive transcription of a downstream gene of interest. Since transcription is only activated at the intersection of the expression patterns of the two hemidrivers, a split driver system can be used to drive expression in a restricted pattern. The p65(AD)::Zip+ hemidriver is compatible with any DNA-binding domain hemidriver containing the Zip- domain. The DNA-binding specificity of the reconstituted transcriptional activator will depend upon the DNA-binding domain present in the DNA-binding domain Zip- hemidriver.