Hemicentin’s role in phosphorylation of the cytoplasmic tail of beta integrin in Caenorhabditis elegans.

The soil nematode C. elegans is an important model organism that has been widely studied and has yielded many important discoveries in biology. Our lab studies integrins in C. elegans. Integrins are a heterodimeric transmembrane cell surface receptor that are involved in cell signaling and the attachment and detachment of cells. They interact with the extracellular matrix (ECM) outside of the cell, and with the largely actin-based cytoskeleton inside the cell. Phosphorylation of the two NPxY (Asn-Pro-x-Tyr) motifs in beta integrin’s cytoplasmic tail plays a role in signaling which can change the conformation of the heterodimer and change its affinity for ECM proteins and cytoskeletal proteins. This signaling works both outside-in and inside-out. Using worms with genetic alterations to the amino acids in their NPxY motifs and worms with non-functional hemicentin ECM proteins, we characterize a relationship between hemicentin and the phosphorylation of beta integrin’s cytoplasmic tail.