Editors' ChoiceRight-Left Asymmetry

PKA Inhibitors in Development

Science's STKE  14 Aug 2001:
Vol. 2001, Issue 95, pp. tw6
DOI: 10.1126/stke.2001.95.tw6

cAMP-dependent protein kinase (PKA) functions in cell type determination in the embryos of Drosophila, zebrafish, and chicks. The α isoform of protein kinase inhibitor (PKI) inhibits the catalytic activity of PKA; however, the endogenous function of PKIα has not been well elucidated. Now, Kawakami and Nakanishi have uncovered a role for PKIα in cell patterning in the developing chick. During the early stages of development, PKIα expression was higher on the right side of Hensen's node in chick embryos; however, symmetric expression of PKIα was observed later in development. Treatment of chick embryos with antisense oligonucleotides to PKIα disrupted the placement of the developing heart and also caused perturbations in the expression of Nodal, and Pitx2, whereas asymmetric expression of Sonic Hedgehog remained normal. PKIα expression was stimulated in chick embryos ectopically treated with activin, suggesting that PKIα may act in an activin-dependent pathway to regulate asymmetric patterning.

M. Kawakami, N. Nakanishi, The role of an endogenous PKA inhibitor, PKIα, in organizing left-right axis formation. Development 128, 2509-2515 (2001). [Online Journal]