COMMUNICATION BETWEEN EPITHELIAL CELL AND MUSCLE CELL

I am an epithelial cell and I have an important role in shaping organs. I contribute to the formation of the epidermis which contains hemidesmosomes and intermediate filaments (IFS) which link the underlying muscles on my basal surface and the external cuticle on my apical surface. The cuticle acts an exoskeleton onto which you, the muscle cells attach to allow locomotion. Other cells called sarcomeres are mechanically coupled to the basal lamina that separates you from me through integrins. In C. elegans, the organism we are a part of, there are only 11 genes coding for IFs which can be divided into five groups; A1-A4, B1-B2, C1-C2, D1-D2 and E1. In embryos or larvae lacking the A2 and A3 become detached from the body wall. Mutants which cause you to detach from the body wall are mua-3 and mup-4 which results in our organism dying during the embryonic or larval stage. MUA-3 and MUP-4 act at the epidermal apical surface, binding my cuticle via the extracellular domain and on the IFs through the filaggrin like cytoplasmic tail.