Lysosomal proteins in cell death and autophagy.

Nearly 60 years ago, lysosomes were first described in the laboratory of Christian de Duve, a discovery that significantly contributed to him being awarded a share of the 1974 Nobel Prize in Physiology or Medicine for elucidating 'the structural and functional organization of the cell'. Initially thought of as a simple waste degradation facility of the cell, these organelles recently emerged as signalling centres with connections to major cellular processes. This review provides an overview of the many roles of lysosomal proteins in two of these processes: cell death and autophagy. We discuss both resident lysosomal proteins as well those that temporarily associate with lysosomes to influence autophagy and cell death pathways. Particular focus is given to studies in mammalian cells and in vivo systems.