The variability of both composition and amount of leaf surface wax from maize leaves (Zea mays L. cv. Oh 43) of different ages, and on different leaves along the plant, was studied by gas chromatography. In addition to visual comparisons of chromatograms, statistical analyses (ANOVA and PCA) were performed. For this cultivar, among the 25 hydrocarbons recognized, the dominant gas chromatography peak of the waxes from young leaves is 1-dotriacontanol, while wax from mature leaves consists predominantly of odd-numbered alkanes. The surface wax of leaves from intermediate-aged plants is a mixture of the seedling and mature waxes. In addition to age-related differences, consistent leaf-related developmental differences were detected. Furthermore, the amount of wax extracted per unit area increased during the first 20 days, declined rapidly until day 50, and declined gradually thereafter.
A simple, rapid, and novel procedure for purifying ferritin from the postnuclear supernatant of red blood cell lysates is described. This report establishes the resistance of commercially available holo- and apo-ferritins to proteinase-K digestion, and documents how the use of this enzyme, in conjunction with the well-documented resistance of ferritins to heat denaturation (75-80 degrees C for 10 min), makes it possible to obtain high yields (greater than 90%) of pure, undegraded ferritin from the postnuclear supernatant of hypotonically or Triton X-100 lysed red blood cells. The resultant purified ferritin contains the same amount of iron as ferritin not treated with proteinase-K and, as judged by one- and two-dimensional gel electrophoresis and electron microscopy, consists of intact ferritin with a subunit isoform composition identical in molecular mass and isoelectric points to that obtained from ferritin prepared in the absence of this enzyme.
Arising from an interest in the degree to which leaf surface wax could be used as a marker for the identification of genetic lines and cultivars of maize (Zea mays L.), this study explored wax variability among five inbred lines (A619, B73, OH43, VA26, and W23) as revealed by gas chromatography. Individual leaves of the five inbred lines were excised from plants harvested at or near anthesis. The surface wax was extracted by a chloroform dip, samples were dried in vacuo and stored at −5°C until analysis. The composition of leaf surface wax varied among the inbreds. The chromatographic patterns of A619 and OH43 were indistinguishable from each other, while the waxes of B73 and W23 differed slightly. The wax of VA26 was the least similar to the waxes of the other inbreds. Different statistical treatments [Analysis of Variance (ANOVA), Principal Components Analysis (PCA), and Average Linkage Clustering (ALC)] of the data derived from gas chromatographic analyses were successful in arranging individual leaves into their inbred groups, with the exception of A619 and OH43. The between inbred variation suggested that leaf surface wax composition can be a suitable character for some inbred characterizations if developmental and leaf number‐based differences are taken into account.
Cultured cells of the spruce budworm (Choristoneura fumiferana) respond to heat shock with the new and/or enhanced synthesis of six proteins with Ms of 84,000, 78,000, 70,000, 68,000, 21,000, and 14,000, as measured by one-and two-dimensional PAGE. The most prominent hsp of these cells is a 78,000 Da protein which is maximally induced at 39°C and which consists of three isoforms with different pl. Hsp 78 is found in the detergent-soluble cytosolic fraction of cell lysates. In vitro translation of RNA extracted from cultured cells and from larvae shows that the induction of hsp 78 is regulated mainly at the transcriptional level.Hsp 78 does not cross-react with a variety of antibodies made to members of the hsp 70 and hsp 83 families. In particular, antibodies to hsp 70 that do cross-react with a 70 kDa protein of C. fumiferana do not cross-reactwith hsp 78. Homologous 75-78 kDa hsps are also present in heat-shocked cells from other lepidopterans (Spodoptera frugiperda and Bornbyx mori). Cfl cells exposed to elevated levels of arsenite or cadmium respond with the new and/or enhanced synthesis of only two of their hsps (hsp 84 and hsp 70); hsp 78 i s not induced by these treatments. The data suggest that hsp 78 of C. fumrferana represents a new family of hsps unique to lepidopterans. o 1994 Witey-Liss, Inc.
Reticulocytes, purified from the blood of quail and chickens recovering from anaemia, respond to heat shock by the new and (or) enhanced synthesis of heat-shock protein (HSPs) with relative molecular masses of greater than 400,000, 90,000, 70,000, and 26,000 (quail) or 24,000 (chicken) and the depressed synthesis of many proteins normally produced at a control temperature. The synthesis of these HSPs is noncoordinate since the expression of each protein depends upon the particular temperature and duration of the time at that temperature. Separation of proteins from quail reticulocytes into Triton X-100 soluble and insoluble fractions demonstrates that the 70,000 and 26,000 Da HSPs are found in both fractions, whereas the greater than 400,000 and 90,000 Da HSPs are located only in the detergent-soluble fraction. Triton X-100 fractionation also reveals that there are three isoelectric variants of the 70,000 Da HSP and that they are constitutively synthesized and selectively partitioned between cellular compartments. Heat shock induced synthesis of the 90,000, 70,000, and 26,000 Da quail HSPs is prevented by actinomycin D, while enhanced synthesis of the greater than 400,000 Da HSP is unaffected by this inhibitor. These results demonstrate that nucleated, terminally differentiating avian red blood cells are capable of responding to heat stress by rapid changes in their highly restricted "program" of gene expression.
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