Extranuclear control

It might be stated that interactions between the nucleus and the cytoplasm are thought to govern cell development and cell differentiation. These interactions, including extranuclear controls, regulate the flow of genetic information. 

In contrast to the morphological strains determined by nuclear genes, the few morphological strains under extranuclear control are less clear-cut morphologically, and are essentially slow-growing, sometimes nonconidiating strains. Certain of these such as poly, and the mi strains, involve respiratory cytochrome alterations similar to petUe yeast, and are typically maternally inherited. 

It does seem clear, however, that extranuclear control of mitochondrial properties, probably through its DNA, is responsible for such cytoplasmic Neurospora mutants as poky, mi, and abnormal, and that further definition and resolution of the control mechanisms involved will be both exciting and rewarding. 

Fig. 9.4. Fluorescence staining for mycoplasma. Cells were stained with Hoechst 33258 which fluoresces with DNA. (a) Vero cells infected with M. arginini which show marked extranuclear fluorescence (b) negative control cells. The photographs (x40) were kindly supplied by Dr. Rae of Moredun Animal Health Ltd.

Temperature-programmed oxidation (TP0) of coke on ZSM-5 was carried out in a 1.0% oxygen-1n-argon mixture. Coked samples were dehydrated at 300°C for 30 minutes in flowing argon before TP0 commenced. Samples (ca. 10 mg) were heated at 10°C min-1 from 300°C to 750°C. Products evolved from the zeolite were analysed in a continously scanning Extranuclear SpectrEL mass spectrometer (model no. 275-50). Flow of the gas mixture was controlled by a fixed capillary leak (10 cm min"1). 

A principal aim of chemical analysis is to develop a theoretical model of the interaction between atoms and molecules. Experimental work of the previous two centuries has resulted in a highly successful empirical account of chemical reactivity, and efforts to formulate a rigorous, fundamental theory as a nonclassical many-body problem have lead to highly accepted and much used methods but these still have significant limitations. By the current approaches, chemical interaction is modeled in terms of probability-density distributions of independent electrons. Although the theory appears to work for one-particle problems, unforeseen effects emerge in the treatment of more complex systems [1]. In particular, the distribution of extranuclear electrons seems to obey an exclusion principle, not anticipated in the basic theory, and there is no fundamental understanding of three-dimensional molecular shapes, as observed experimentally. The pivotal role of entropy, which controls the course of chemical reactions, is theoretically equally unexpected. 

It seems clear that the mechanism of control of the abn phenotype is closely related to the cytochrome pattern, whieh, in turn, is probably related to the overall metabolic pattern and to cell wall synthesis. There is no evidence of qualitative changes in cytochromes. As clearly shown by Sherman et al. (1966), yeast cytochrome c at least is controlled by nuclear structural genes. As in yeast extranuclear petites,... 

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