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31.
An update of mouse and human HOX gene nomenclature 总被引:4,自引:0,他引:4
D Duboule E Boncinelli E DeRobertis M Featherstone P Lonai G Oliver F H Ruddle 《Genomics》1990,7(3):458-459
32.
U Seidel E Bober B Winter S Lenz P Lohse H W Goedde K H Grzeschik H H Arnold 《Gene》1988,66(1):135-146
A set of cDNA clones coding for alkali myosin light chains (AMLC) was isolated from fetal human skeletal muscle. Nucleotide sequence analysis and RNA expression patterns of individual clones revealed related sequences corresponding to (i) fast fiber type MLC1 and MLC3; (ii) the embryonic MLC that is also expressed in fetal ventricle and adult atrium (MLCemb); and (iii) a nonsarcomeric MLC isoform that is found in all nonmuscle cell types and smooth muscle. The AMLC gene family in man comprises unique copies for MLC1, MLC3 and MLCemb, and multiple copies for the nonsarcomeric MLC genes. The gene coding for MLC1 and MLC3 is located on human chromosome 2. 相似文献
33.
34.
Vera Yip Mary Ellen Pusateri Joyce Carter Irwin A. Rose Oliver H. Lowry 《Journal of neurochemistry》1988,50(2):594-602
The distribution of glucose-1,6-bisphosphate (G16P2) synthase was measured in more than 70 regions of mouse brain, and nine layers of monkey retina. Activities in gray areas varied as much as 10-fold, in a hierarchical manner, from highest in telencephalon, especially the limbic system, to lowest in cerebellum, medulla, and spinal cord. The synthase levels were significantly correlated among different regions with G16P2 itself, as well as with previously published levels of a brain specific IMP-dependent G16P2 phosphatase. In contrast, neither G16P2 nor either its synthase or phosphatase correlated positively with phosphoglucomutase, and in all regions the G16P2 levels greatly exceeded requirements for activation of this mutase. This strengthens the view that G16P2 has some function besides serving as coenzyme for phosphoglucomutase. However, attempts to correlate the "G16P2 system," as defined by the three coordinately related elements, synthase, phosphatase, and G16P2, with other enzymes of carbohydrate metabolism, or with regional data of Sokoloff et al. [J. Neurochem. 28, 897-916 (1977)] for glucose consumption, were unsuccessful. This leaves open the possibility that brain G16P2 might serve as a phosphate donor for specific nonmetabolic effector proteins. 相似文献
35.
Subunit location of the iron-sulfur clusters in fumarate reductase from Escherichia coli 总被引:3,自引:0,他引:3
M K Johnson A T Kowal J E Morningstar M E Oliver K Whittaker R P Gunsalus B A Ackrell G Cecchini 《The Journal of biological chemistry》1988,263(29):14732-14738
The subunit location of the [2Fe-2S], [3Fe-4S], and [4Fe-4S] clusters in Escherichia coli fumarate reductase has been investigated by EPR studies of whole cells or whole cells extracts of a fumarate reductase deletion mutant with plasmid amplified expression of discrete fumarate reductase subunits or groups of subunits. The results indicate that both the [2Fe-2S] and [3Fe-4S] clusters are located entirely in the iron-sulfur protein subunit. Information concerning the specific cysteine residues that ligate these clusters has been obtained by investigating the EPR characteristics of cells of the deletion mutant amplified with a plasmid coding for the flavoprotein subunit and a truncated iron-sulfur protein subunit. While the results are not definitive with respect to the location of the [4Fe-4S] cluster, they are most readily interpreted in terms of this cluster being entirely in the flavoprotein subunit or bridging between the two catalytic domain subunits. These new results are discussed in light of the amino acid sequences of the two subunits and the sequences of structurally well characterized iron-sulfur proteins containing [2Fe-2S], [3Fe-4S], and [4Fe-4S] centers. 相似文献
36.
R F Stump J R Pfeiffer J Seagrave J M Oliver 《The journal of histochemistry and cytochemistry》1988,36(5):493-502
Immunogold labeling and silver enhancement techniques are widely used to determine density and distribution of cell membrane receptors by light and transmission electron microscopy. However, these techniques have not been widely used for receptor detection by scanning electron microscopy. We used antigen- or protein A-conjugated colloidal gold particles, together with silver enhancement, sequential secondary and back-scattered electron imaging (SEI and BEI), and digital image processing, to explore cell surface distribution of IgE-receptor complexes on RBL-2H3 cells, a rat leukemia line that provides a model for the study of mucosal mast cells. Cells were first incubated with a monoclonal antidinitrophenol IgE (anti-DNP-IgE) that binds with high affinity to cell surface IgE receptors. The resulting IgE-receptor complexes were cross-linked either with the multivalent antigen, DNP-BSA-gold, or with a polyclonal anti-IgE antibody. Antibody-treated cells were labeled after fixation with protein A-gold. Fixed, gold-labeled cell monolayers were silver enhanced (or not), dehydrated, critical point-dried, and coated with gold-palladium (for SEI analysis) or carbon (for combined SEI/BEI analysis). They were observed in an Hitachi S800 SEM equipped with a field emission tip and a Robinson backscattered electron detector. An image processor (MegaVision 1024XM) digitized images directly from the S800 microscope at 500-1000 line resolution. Silver enhancement significantly improves detection of gold particles in both SEI and BEI modes of SEM. On gold-palladium-coated samples, 20-nm particles are resolved by SEI after enhancement. BEI resolves 15-nm particles without enhancement and 5- or 10-nm particles are resolved by BEI on silver-enhanced, carbon-coated samples. Neither BEI nor SEI alone can yield high resolution topographical maps of receptor distribution (BEI forms images on the basis of atomic number contrast which reveals gold but not surface features). Image analysis techniques were therefore introduced to digitize, enhance, and process BEI and SEI images of the same field of view. The resulting high-contrast, high-resolution images were superimposed, yielding well-resolved maps of the distribution of antigen-IgE-receptor complexes on the surface of RBL-2H3 mast cells. The maps are stored in digital form, as required for computer-based quantitative morphometric analyses. These techniques of silver enhancement, combined BEI/SEI imaging, and digital image analysis can be applied to analyze density and distribution of any gold-labeled ligand on its target cell. 相似文献
37.
38.
Detection of point mutations in human DNA by analysis of RNA conformation polymorphism(s). 下载免费PDF全文
P V Danenberg T Horikoshi M Volkenandt K Danenberg H J Lenz L C Shea A P Dicker A Simoneau P A Jones J R Bertino 《Nucleic acids research》1992,20(3):573-579
RNA molecules were found to separate into numerous metastable conformational forms upon non-denaturing gel electrophoresis. The equilibration of the conformations was accelerated by heating or mild denaturing conditions. Single-base substitutions in the sequence of the RNAs caused changes in the conformational patterns, including mobility shifts of major and minor conformations, appearance of new conformations and loss of other conformations. This sequence-dependent RNA conformational polymorphism was used to detect point mutations in p53 and, dihydrofolate reductase genes. Sense and anti-sense RNA strands corresponding to the same segment of the p53 gene gave entirely different conformational patterns. To generate the RNA, short regions of the target genes (up to about 250 bp) were amplified by the polymerase chain reaction and the resulting DNA segments transcribed to RNA by T7 RNA polymerase. The method is rapid, simple, amenable to non-radioactive visualization and was successful in several cases when DNA single-strand conformational polymorphism analysis (Orita et al. (1989) Genomics 5, 874-879) failed to detect the point mutation. 相似文献
39.
Proliferation of the MAC-T bovine mammary epithelial cell line in the presence of mammary secretion whey proteins. 总被引:3,自引:0,他引:3
J J Rejman S P Oliver R A Muenchen J D Turner 《Cell biology international reports》1992,16(10):993-1001
Development of the MAC-T bovine mammary epithelial cell line by stable transfection with simian virus-40 large T-antigen should greatly assist study of possible intrinsic (local) and extrinsic (systemic) factors regulating bovine mammary epithelial cell development, differentiation, and function. This study evaluated the influence of mammary secretion whey proteins alpha-lactalbumin (ALA), beta-lactoglobulin (BLG), lactoferrin (LF), transferrin (TF) and serum albumin (SA) on MAC-T cell proliferation in the absence and presence of 10% fetal bovine serum (FBS). Concentration of whey proteins in culture ranged from 0 to 625 micrograms/ml. MAC-T cell proliferation in the absence of FBS was significantly lower than in the presence of 10% FBS. Alpha-lactalbumin and LF significantly decreased MAC-T proliferation in both the absence and presence of 10% FBS. Transferrin significantly increased MAC-T cell proliferation only in the absence of FBS. There were no significant differences in MAC-T cell proliferation cultured in the presence of BLG or SA. These experiments illustrate the potential usefulness of MAC-T cells for the study of factors involved in mammary cell proliferation. Results identified ALA, LF and TF as possible intrinsic factors associated with regulation of mammary epithelial cell proliferation. 相似文献
40.
Influence of Protoplasmic Water Loss on the Control of Protein Synthesis in the Desiccation-Tolerant Moss Tortula ruralis: Ramifications for a Repair-Based Mechanism of Desiccation Tolerance 总被引:9,自引:1,他引:8 下载免费PDF全文
Oliver MJ 《Plant physiology》1991,97(4):1501-1511
Desiccation tolerance of the moss Tortula ruralis is characterized by a desiccation-induced change in gene expression that becomes evident upon rehydration. As reported earlier, this change in gene expression is apparently brought about by a change in the control of translation and does not include a major shift in mRNA abundance. A full qualitative and quantitative analysis of the alteration in gene expression, which is characterized by the loss of (or greater than fivefold decrease in) the synthesis of 25 hydration (h) proteins and initiation (or greater than fivefold increase) of the synthesis of 74 rehydration (r) proteins, is given in this report. Exposure to a desiccating atmosphere, for times that result in varying levels of water loss, enabled the determination that the control of synthesis of r proteins is different from the control of synthesis of h proteins. The r and h protein synthesis responses are internally coordinate, however. Similarly, the return to normal levels of h protein synthesis differs from that of the r proteins. The return to normal synthetic levels for all h proteins is synchronous, but the rate of loss of r protein synthesis varies with each individual r protein. Run-off translation of polysomes isolated from gametophytes during the drying phase demonstrates that there are no novel mRNAs recruited and no particular mRNA is favored for translation during desiccation. These findings add credence to the argument that translational control is the major component of the desiccation-induced alteration in gene expression in this plant, as discussed. Aspects of the response of protein synthesis to desiccation are consistent with the hypothesis that T. ruralis exhibits a repair-based mechanism of desiccation tolerance. 相似文献