Plant Cell Death And Cell Differentiation
Published 2004 · Biology
Publisher Summary . Programmed cell death (PCD) occurs in a wide range of cell types during differentiation and plays an important role during plant development and survival. PCD in plant cells follows many divergent and independent pathways. This chapter focuses on whether or not PCD in plant cell differentiation parallels apoptosis in animal cells and whether PCD in plant cells follows many divergent and independent pathways or has a common basis. Cytosolic Ca 2+ is one second-messenger that is implicated in many different cell types during PCD. Apoptosis in animal cells often involves fragmentation into membrane-bound apoptotic bodies that are quickly engulfed by surrounding macrophages or phagocytes, but no such mechanism for dealing with dead cells is available to plants. PCD plays important roles throughout plant development. It occurs throughout the plant life cycle and also in many parts of the plant and even whole plants. Cell death occurs during pollination. Hair cells on the stigmatic surface, cells in the style in the pathway of the pollen tube, and cells in the nucellus die shortly after pollen germination or before flower opening. After fertilization, synergid, antipodal, endosperm, coleorhiza, and nucellar pillar cells die. These events are all assumed to represent PCD.