We reported previously the purification of a 165kDa muscle-specific protein identified by virtue of its ability to bind ‘261-labeled low density lipoprotein with high affinity after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Hofmann, S. L., Brown, M. S . , Lee, E., Pathak, R. K., Anderson, R. G. W., and Goldstein, J. L. (1989) J. Biol. Chem. 264, 82608270). The protein is locate...