The M{3xP3-RFP.attP} element acts as a landing site for integration of DNA into the genome at a defined location; the element contains an attP site at its 5' end, which acts as a target site for phiC31:int-mediated integration of any attB site-containing donor plasmid. The element also contains a Disc\RFP3xP3.PB marker that is flanked by loxP sites (oriented in the same direction), allowing for excision of the marker using P1cre recombinase. The attP site present in this element contains a T-C transition at position 26 downstream of the TTG site. This mutation is outside of the attP 'core region' of 39bp (minimal attP length defined in PMID:10801973) and is also outside the 'footprint' region bound by phiC31:int integrase (PMID:11069650) and so is not expected to affect the function of the attP site.