Lipid Regulator Shapes Heart, Lung Development

(MEMPHIS, Tenn. - July 27, 2026) St. Jude Children's Research Hospital scientists uncovered a regulatory mechanism for signaling of Sonic Hedgehog (SHH), a pathway essential for embryonic development. Researchers found that the lipid (or fatty acid) arachidonic acid boosts the activity of Smoothened (a protein that relays SHH signals inside cells) through a newly discovered binding site that alters the receptor's behavior to enhance its signaling activity. Disrupting this interaction impaired heart and lung development, revealing how precise control of SHH signaling guides tissue formation. The findings, published in Nature Communications , provide insight into how this pathway may be modulated in diseases such as cancer.