Locus of crossover in P1 site (loxP) (loxP)

The Locus of crossover in P1 (loxP) site is a 34-base pair DNA sequence derived from the bacteriophage P1, consisting of two 13-bp inverted repeats flanking an 8-bp asymmetric spacer region (Sauer, B., Mol Cell Biol, 1987). It serves as the specific recognition substrate for Cre recombinase, an enzyme that catalyzes site-specific DNA recombination between two such sites (Nagy, A., Genesis, 2000). In the context of transduced Postn-expressing cells, these sites are typically integrated into the genome of cells expressing Periostin (Postn), a protein primarily associated with the extracellular matrix and activated fibroblasts during tissue repair, cardiac remodeling, and fibrosis (Takeda, N., et al., J Clin Invest, 2010). This experimental configuration allows for the conditional deletion, inversion, or translocation of specific genetic sequences within the Postn-positive cell lineage, providing a powerful tool for lineage tracing and functional genomics in cardiovascular and fibrotic disease research (Kuhn, R., & Schwenk, F., Methods Mol Biol, 1997). While loxP sites are not endogenous human therapeutic targets, they are essential components of gene therapy strategies and preclinical models designed to modulate gene expression in a cell-type-specific manner. Therapeutic challenges for clinical translation include the potential for off-target recombination at 'pseudo-loxP' sites in the human genome and the potential immunogenicity of the bacterial Cre protein.

Other names

loxP siteloxP sequenceCre-recombination siteLocus of crossover in P1

Cre-mediated site-specific recombination between two loxP sites to induce DNA deletion, inversion, or translocation.