Kcnj13 Conditional Knockout mouse models

Kcnj13, the mouse ortholog of human KCNJ13, encodes Kir7.1, an atypical inward rectifier with unusually low single-channel conductance and weak dependence on extracellular potassium, properties traced to a methionine at the position occupied by arginine in other Kir channels. Kir7.1 is concentrated at the apical membrane of retinal pigment epithelium, where it colocalizes with the sodium pump and sets subretinal potassium levels, and it is also expressed in choroid plexus, thyroid, and uterine smooth muscle. Human mutations cause snowflake vitreoretinal degeneration through dominant-negative gating changes and Leber congenital amaurosis type 16 through recessive loss of function, giving a clear allele fork between knockin and null. Constitutive mouse nulls die within a day of birth with cleft palate and feeding failure, so retinal pigment epithelium-restricted conditional deletion using Best1-Cre or an inducible driver is required to study photoreceptor survival and electroretinogram c-wave endpoints in adults, and humanized alleles support gene replacement testing.

Conditional deletion of Kcnj13 limits the genetic change to the lineage you choose. That helps in oncology, immunology, and metabolic work where systemic loss would muddy the read. After you confirm Cre specificity, crossing to Kcnj13 floxed stock yields usable cohorts.