Cell death processes associated with

Once apoptosis is triggered, a stereotyped sequence of premitochondrial events occurs that executes the cell death process. In many cases proteins and/or lipid mediators that induce changes in mitochondrial membrane permeability and calcium regulation are produced or activated. For example, the pro-apoptotic Bcl-2 family members Bax, Bad and Bid may associate with the mitochondrial membrane and modify its permeability. Membrane-derived lipid mediators such as ceramide and 4-hydroxynonenal can also induce mitochondrial membrane alterations that are critical for the execution of apoptosis. 

Apoptosis or programmed cell death is a highly regulated process required in developmental events such as embryological tissue remodelling and the endometrial changes of the menstrual cycle. The cell complement in particular tissues of metazoans derives from a balance between apoptosis and cell division and an imbalance in favour of cell multiplication is associated with cancer. 

A number of other enzymes deserve consideration because they are involved in pathways that are closely linked to nitrogen metabolism, such as Rubisco and other carboxylases that are critical to the coupling of C and N metabolism (Huppe and Turpin, 1994), or electron transport system (ETS) enzymes such as isocitrate dehydrogenase that are involved in respiratory metabolism (Roy and Packard, 2001). Others are relevant to N losses (e.g., esterases that are used as indices of cell lysis Agusti et al., 1998 or proteases associated with active cell death processes, e.g., Berman-Frank et al, 2004) (Table 32.1). 

Apoptosis, a form of cell death (Ap oh tosis or A pop tosis Greek apo , meaning leaf ptosis , meaning falling off), is a genetically self-orchestrated naturally occurring cell death process that is associated with the course of development and induced during... 

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