Cleft Palate, Moderate Lung Developmental Retardation and Early Postnatal Lethality in Mice Deficient in the Kir7.1 Inwardly Rectifying K+ Channel

TL;DR

Mice lacking the Kir7.1 potassium channel die shortly after birth and show cleft palate and lung development issues, suggesting the channel is important for palate and lung development.

Contribution

The study identifies a new role for Kir7.1 in palatogenesis and respiratory system development in mice.

Findings

Homozygous Kir7.1-deficient mice die hours after birth and exhibit cleft palate.

Kir7.1 is expressed in epithelial cells of the respiratory tree and may be essential for lung development.

The channel appears to play a critical role in late palatogenesis.

Abstract

Kir7.1 is an inwardly rectifying K+ channel of the Kir superfamily encoded by the kcnj13 gene. Kir7.1 is present in epithelial tissues where it colocalizes with the Na+/K+-pump probably serving to recycle K+ taken up by the pump. Human mutations affecting Kir7.1 are associated with retinal degeneration diseases. We generated a mouse lacking Kir7.1 by ablation of the Kcnj13 gene. Homozygous mutant null mice die hours after birth and show cleft palate and moderate retardation in lung development. Kir7.1 is expressed in the epithelium covering the palatal processes at the time at which palate sealing takes place and our results suggest it might play an essential role in late palatogenesis. Our work also reveals a second unexpected role in the development and the physiology of the respiratory system, where Kir7.1 is expressed in epithelial cells all along the respiratory tree.

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