Twisted gastrulation (tsg) encodes a BMP binding protein that makes a tripartite complex with the product of sog and a heterodimer formed with the products of dpp and scw. This complex is a favoured substrate for the product of tld, which processes the product of sog and liberates the heterodimer formed with the products of dpp and scw.

Receptor protein serine/threonine kinase; Saxophone (sax) encodes a type I BMP receptor. Together with the BMP receptors encoded by tkv and put, it transduces signaling of the BMP ligands encoded by dpp, gbb and scw, in a wide variety of developmental processes including embryonic and imaginal disc patterning; Belongs to the protein kinase superfamily. TKL Ser/Thr protein kinase family. TGFB receptor subfamily.

Dorsal-ventral patterning protein Sog; Short gastrulation (sog) encodes a secreted BMP antagonist that is expressed in the embryonic ventral neuroectoderm. sog product promotes neural development by preventing dorsally produced dpp from diffusing into the neuroectoderm and suppressing expression of neural genes. sog protein also diffuses dorsally where it helps establish a BMP activity gradient essential for partitioning that domain into cells giving rise to the dorsal epidermis versus amnioserosa.

Protein decapentaplegic; Required during oogenesis for eggshell patterning and dorsal/ventral patterning of the embryo. Acts as a morphogen during embryogenesis to pattern the dorsal/ventral axis, specifying dorsal ectoderm and amnioserosa cell fate within the dorsal half of the embryo; this activity is antagonized by binding to sog and tsg. Induces the formation of visceral mesoderm and the heart in early embryos. Required later in embryogenesis for dorsal closure and patterning of the hindgut. Also functions postembryonically as a long-range morphogen during imaginal disk development [...]

Dorsal-ventral patterning protein tolloid; Tolloid (tld) encodes a member of the asticin metalloprotease family. Its primary function is to cleave the product of sog, which facilitates the diffusion of the ligand encoded by dpp to the dorsal-most cells in the early blastoderm embryo, helping to specify formation of the amnioserosa.

Serine/threonine-protein kinase receptor; Punt (put) encodes a transforming growth factor beta type II receptor that functions in both Dpp/BMP and Activin signaling. Pathway specificity in signaling output is determined by which type I receptor (Dpp/BMP or Activin one) is engaged in the complex with the product of put; Belongs to the protein kinase superfamily. TKL Ser/Thr protein kinase family. TGFB receptor subfamily.

Receptor protein serine/threonine kinase; Baboon (babo) encodes the type I receptor for the activin-like ligands encoded by daw, Actbeta and myo. There are three isoforms of the product of babo that differ only in their extracellular domain likely resulting in different ligand binding specificity. It can form a complex with the type II receptors put or wit in the presence of an activin like ligand. This results in the transcriptional regulation of activin responsive genes; Belongs to the protein kinase superfamily. TKL Ser/Thr protein kinase family. TGFB receptor subfamily.

Mothers against decapentaplegic homolog; Smad on X (Smox) encodes the primary transcription factor that mediates Activin signalling. Upon phosphorylation by the receptor encoded by babo, it forms a complex with the co-Smad protein encoded by Med. This complex translocates to the nucleus where it regulates expression of target genes.

Myoglianin, isoform A; Myoglianin (myo) encodes a protein expressed primarily in muscle and glia cells. Mutations in myo affect neuronal remodeling during metamorphosis by failing to activate EcR expression in the remodeling neurons.