Do all programmed cell deaths occur via apoptosis?

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 90; no. 3; pp. 980 - 984
• Main Authors: Schwartz, L.M. (University of Massachusetts, Amherst, MA), Smith, S.W, Jones, M.E.E, Osborne, B.A
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 01.02.1993; National Acad Sciences; National Academy of Sciences
• Subjects: Ageing, cell death; Animals; Apoptosis; Apoptosis - physiology; BIOLOGIA; Biological and medical sciences; BIOLOGIE; Cell death; Cell Death - physiology; Cell lines; Cell Nucleus - ultrastructure; Cell physiology; Cells; Cellular biology; CELLULE; CELULAS; Chromosomes - ultrastructure; Death; Deoxyribonucleic acid; DNA; DNA Damage; ESTRUCTURA CELULAR; Fundamental and applied biological sciences. Psychology; In kind support and maintenance; Lepidoptera; MANDUCA SEXTA; Metamorphosis, Biological - physiology; Mice; Mice, Inbred BALB C; Molecular and cellular biology; MORT; Moths; MUERTE; Muscles - physiology; Muscles - ultrastructure; Neurons; RNA; Sphingidae; STRUCTURE CELLULAIRE; T lymphocytes; T-Lymphocytes - physiology; T-Lymphocytes - ultrastructure; Intersegmental muscle; Insecta; Sphingidae; Electron microscopy; Mechanism; Cell death; Arthropoda; DNA; Morphology; Lepidoptera; T-Lymphocyte; Development; Manduca sexta; Invertebrata; Comparative study
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.90.3.980

During development, large numbers of cells die by a nonpathological process referred to as programmed cell death. In many tissues, dying cells display similar changes in morphology and chromosomal DNA organization, which has been termed apoptosis. Apoptosis is such a widely documented phenomenon that many authors have assumed all programmed cell deaths occur by this process. Two well-characterized model systems for programmed cell death are (i) the death of T cells during negative selection in the mouse thymus and (ii) the loss of intersegmental muscles of the moth Manduca sexta at the end of metamorphosis. In this report we compare the patterns of cell death displayed by T cells and the intersegmental muscles and find that they differ in terms of cell-surface morphology, nuclear ultrastructure, DNA fragmentation, and polyubiquitin gene expression. Unlike the T cells, which are known to die via apoptosis, we find that the intersegmental muscles display few of the features that characterize apoptosis. These data suggest that more than one cell death mechanism is used during development.