INTRACELLULAR PROTEIN CATABOLISM - A MAJO R BIOLOGICAL FUNCTION .2. EXAMPLES OF CONDITIONAL DEGRADATION AND GENESIS OF ANTIGENIC PEPTIDES

Protein catabolism is of major importance for cell physiology. It is r esponsible for the elimination of peptides, the accumulation of which would turn out to be toxic. It is also involved in the control of key steps of cell differentiation and proliferation. Moreover, it is at th e origin of the specific immune response through the production of ant igenic peptides. We have previously detailed the intimate mechanisms o f protein degradation (m/s n degrees 6, vol. 11, p. 723). Herein, we p resent examples of regulated degradation along with the processes invo lved in the production of peptides presentable by the major histocompa tibility complex molecules.