Di Cola D, Pratt G, Rechsteiner M
Institute of Biochemical Science, Faculty of Medicine, University of Chieti, Italy.
FEBS Lett. 1991 Mar 11;280(1):137-40. doi: 10.1016/0014-5793(91)80222-o.
Rabbit red blood cells of various ages were separated on Percoll gradients and the activities of two large cytosolic proteases were measured. Both the multicatalytic protease (MCP), assayed by hydrolysis of fluorigenic peptides, and the 26 S ubiquitin/ATP-stimulated protease, assayed by degradation of ubiquitin-lysozyme conjugates, declined 3-fold or less during maturation of rabbit reticulocytes to erythrocytes. The ability of MCP to hydrolyze three classes of peptides decreased in parallel indicating that the 20 S protease is not significantly remodeled during red blood cell maturation.
