Collagen is the most abundant protein in vertebrates and in the nematode,. C. elegans. Proper folding and post-translational modifications of the. polypeptides are crucial to forming functional extra-cellular matrices like. basement membranes and the cuticle.. C. elegans encodes a large number of cuticular collagens that are. expressed in a sequential temporal fashion prior to each molt. A number of. these collagens when mutated result in phenotypes that affect body shape. and morphology, in particular the Dpy phenotype. Broadly, collagen. mutations fall into two distinct classes, glycine substitutions in the. repetitive Gly-X-Y sequence which disrupt formation of the triple helix and. result in retention of misfolded collagen in the ER, plus alleles that. include genetic nulls which don''t make anything recognized as collagen.. Clearly the latter type do not result in accumulation of misfolded collagen. in the ER, however they can prevent the assembly of their obligate partner. collagens.. Patterns of genetic interaction between different cuticle collagen genes. are extremely complex and the molecular basis of the patterns of epistasis. are not understood. We have been studying the molecular behavior of alleles. of
dpy-7 and from a modifier genetic screen in a
dpy-7(
e88) glycine. substitution background we identified glycine substitution mutants of. another collagen,
rol-6. We find differences in the interactions of glycine. substitution alleles versus genetics nulls which point to different. cellular process being perturbed by the different classes of collagen. mutant. Our current interest is the molecular basis of these differences.. Do not add objects such as pictures, boxes, headers, footers, footnotes,. etc.