Back

Receptor Allostery Promotes Context-Specific Sonic Hedgehog Signaling During Embryonic Development

Ansari, S. S.; Dillard, M. A.; Ghonim, M.; Zhang, Y.; Stewart, D. P.; Canac, R.; Moskowitz, I. P.; Wright, W. C.; Daly, C. A.; Pruett-Miller, S. M.; Steinberg, J.; Wang, Y.-D.; Chen, T.; Thomas, P.; Bridges, J. P.; Ogden, S. K.

2025-01-29 developmental biology
10.1101/2025.01.28.635336 bioRxiv
Show abstract

Sonic Hedgehog (SHH) signaling functions in temporal- and context-dependent manners to pattern diverse tissues during embryogenesis. The signal transducer Smoothened (SMO) is activated by sterols, oxysterols, and arachidonic acid (AA) through binding pockets in its extracellular cysteine-rich domain (CRD) and 7-transmembrane (7TM) bundle. In vitro analyses suggest SMO signaling is allosterically enhanced by combinatorial ligand binding to these pockets but in vivo evidence of SMO allostery is lacking. Herein, we map an AA binding pocket at the top of the 7TM bundle and show that its disruption attenuates SHH and sterol-stimulated SMO induction. A knockin mouse model of compromised AA binding reveals that homozygous mutant mice are cyanotic, exhibit high perinatal lethality, and show congenital heart disease. Surviving mutants demonstrate pulmonary maldevelopment and fail to thrive. Neurodevelopment is unaltered in these mice, suggesting that context-dependent allosteric regulation of SMO signaling allows for precise tuning of pathway activity during cardiopulmonary development.

Matching journals

The top 4 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.