Which molecule inhibits BMP signaling in C. elegans development?
Bone morphogenetic protein signaling must be tightly modulated by extracellular antagonists conserved from flies to mammals. Noggin, Chordin, Sclerostin, Gremlin bind BMP ligands BMP2/4-like DBL-1 and SMA-6 receptor ligands preventing receptor engagement with ALK-SMAD cascade. In C. elegans, homologous antagonists shape dorsal-ventral patterning indirectly via sma-9. Noggin exemplifies inhibition by sequestering BMPs with cysteine-rich domain creating low BMP zones allowing neural induction. This mirrors Spemann organizer secreting Chordin to dorsalize ectoderm during gastrulation, conserving
Ref: Gilbert, Developmental Biology, 12th ed., Chapter 9: BMP antagonists Noggin and Chordin dorsalize organizer and inhibit signaling.
