C. elegans SMA-10 regulates BMP receptor trafficking

摘要: Signal transduction of the conserved transforming growth factor-β (TGFβ) family signaling pathway functions through two distinct serine/threonine transmembrane receptors, type I and II receptors. Endocytosis orchestrates assembly complexes by coordinating entry receptors with their downstream mediators. Recently, we showed that C. elegans bone morphogenetic protein (BMP) receptor SMA-6, part TGFβ family, is recycled retromer complex while receptor, DAF-4 in a retromer-independent, ARF-6 dependent manner. From genetic screens aimed at identifying new modifiers BMP signaling, reported on SMA-10, LRIG (leucine-rich immunoglobulin-like domains) protein. It positive regulator binds to SMA-6 receptor. Here show loss sma-10 leads aberrant endocytic trafficking resulting its accumulation intracellular endosomes including early endosome, multivesicular bodies (MVB), late endosome reduction strength. Our studies defects caused are not universal, but affect only limited set Likewise, Drosophila, find fly homolog sma-10, lambik (lbk), reduces strength pathway, consistent function suggesting evolutionary conservation function. Loss results reduced ubiquitination possible mechanism for regulation signaling.