Generation of Venus reporter knock-in mice revealed MAGI-2 expression patterns in adult mice.

The membrane-associated guanylate kinase inverted 2 (MAGI-2) protein, which is known to localize at the tight junction of epithelial cells, contains multiple copies of the PDZ and WW domains in its structure. Although the expression pattern of Magi2 mRNA in representative organs has been previously published, its detailed cellular distribution at the histological level remains unknown. Such detailed information would be useful to clarify the biological function of MAGI-2. Here, we report the generation of Venus reporter knock-in mice for Magi2 in which exon 6 of the gene was substituted by the Venus-encoding sequence. We detected the expression of the Venus reporter protein in kidney podocytes from these knock-in mice. We also detected Venus reporter protein expression in spermatids within the testes and within neurons in various regions of the brain. Detection of the reporter protein from these diverse locations indicated the endogenous expression of MAGI-2 in these tissues. Our data suggested a potential function of MAGI-2 in the glomerular filtration process and sperm cell maturation. These data indicate that the Venus reporter knock-in mouse for Magi2 is a useful model for the further study of Magi2 gene function.