Microspectrofluorometry for metabolic control analysis and the study of organelle morphogenesis in cell differentiation and transformation

Microspectrofluorometry has been used in conjunction with fluorescence micrography for metabolic control analysis in normal and genetically deficient human fibroblasts, as well as human melanoma cells. These studies point to the role of mitochondria as the `cell's policeman' with regard to metabolic control. Cytotoxic agents active on mitochondrial structure and function (i.e. anthralin, azelaic acid) produce an unleashing of extramitochondrial pathways characterized by large and out-of-control NAD(P)H transients elicited by microinjected substrates. An interesting aspect has been the demonstration of an active nuclear energy metabolism, by NAD(P)H fluorescence excited at 365 nm, which may help to link cell bioenergetics to gene expression in the eukaryotes by the use of DNA probes. The metabolic control analysis of cell bioenergetics has been extended to the pathways involved in the cell's handling of cytotoxic agents. Non invasive fluorescence equipment offers possibilities for diagnostics and therapeutics in dermatology. Structure and function studies can be carried out at considerably enhanced resolution and with on-line interpretation by introducing scanning nearfield optics microscopy (SNOM) and real-time interactive parameter experimentation control (RIPEC).