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Peter H. Quail Winslow R. Briggs Joanne Chory Roger P. Hangarter Nicholas P. Harberd Richard E. Kendrick Maarten Koornneef Brian Parks Robert A. Sharrock Eberhard Schäfer William F. Thompson Garry C. Whitelam 《Plant Molecular Biology Reporter》1994,12(2):S50-S56
These recommendations for genes encoding phytochromes were developed independently by Quail et al., but are broadly consistent
with the Commission's guidelines. Their original article, kindly provided in advance of publication, appeared as a Letter
to the Editor inPlant Cell (6:468–471, 1994) and is published with permission of the American Society of Plant Physiologists. 相似文献
44.
The cDNA and a partial genomic sequence of a rat class I major histocompatibility (RT1) gene, 11/3R, is reported here. The sequence contains several unique amino acid residues at certain positions, mutations in exon 7 (which is not expressed), a mutation of the canonical exon 8 stop codon to a sense codon, and includes a long 3 unstranslated region (utr). The structure of exon 7 differs from that found in most rat class I genes and resembles exon 7 of most H-2K,D,L.Q genes. Parts of the 3 noncoding region are homologous to the RT1.A-4 and certain H-2 genes. Expression is detectable by northern blot analysis in mitogen-stimulated lymphocytes only, by polymerase chain reaction (PCR) in each tissue tested. After transfection into L cells 11/3R can be shown to be expressible at the cell surface. Probes derived from the 3 noncoding part crosshybridize with a number of restriction fragments which map to the RT1.C region, thus defining a subfamily of RT1.C region genes. Several members of this subfamily are deleted in the M1 RT1 mutant. The 11/3R gene presents typical features of a class Ib gene. Aspects of evolution and the potential of the gene are discussed.The nucleotide sequence data reported in this paper have been submitted to the GenBank molecule sequence data base and have been assigned the accession numbers X67503 ande X67504. 相似文献
45.
The anion channel protein from Clavibacter michiganense ssp. nebraskense (Schürholz, Th. et al. 1991, J. Membrane Biol. 123: 1-8) was analyzed at different concentrations of KCl and KF. At 0.8 M KCl the conductance G(Vm) increases exponentially from 21 pS at 50 mV up to 53 pS at Vm = 200 mV, 20°C. The concentration dependence of G(Vm) corresponds to a Michaelis-Menten type saturation function at all membrane voltage values applied (0-200 mV). The anion concentration K0.5, where G(Vm) has its half-maximum value, increases from 0.12 M at 50 mV to 0.24 M at 175 mV for channels in a soybean phospholipid bilayer. The voltage dependence of the single channel conductance, which is different for charged and neutral lipid bilayers, can be described either by a two-state flicker (2SF) model and the Nernst-Planck continuum theory, or by a two barrier, one-site (2B1S) model with asymmetric barriers. The increase in the number of open channels after a voltage jump from 50 mV to 150 mV has a time constant of 0.8 s. The changes of the single-channel conductance are much faster (<1 ms). The electric part of the gating process is characterized by the (reversible) molar electrical work ΔGθel = ρZgFVm ≈ -1.3 RT, which corresponds to the movement of one charge of the gating charge number |Zg| = 1 across the fraction ρ = ΔVm/Vm = 0.15 of the membrane voltage Vm = 200 mV. Unlike with chloride, the single channel conductance of fluoride has a maximum at about 150 mV in the presence of the buffer PIPES (≥5 mM, pH 6.8) with K0.5 ≈ 1 M. It is shown that the decrease in conductance is due to a blocking of the channel by the PIPES anion. In summary, the results indicate that the anion transport by the Clavibacter anion channel (CAC) does not require a voltage dependent conformation change of the CAC. 相似文献
46.
Hans Eberhard Fischer 《Genetica》1959,29(1):155-171
Ohne Zusammenfassungmit 6 AbbildungenHerrn Prof. Dr. R. Bauch zum 60. Geburtstag gewidmet. 相似文献
47.
Carsten Mei?ner Reinhold Deppisch Friederike Hug Matthias Schulze Eberhard Ritz Horst Ludwig Gertrud M. H?nsch 《Glycoconjugate journal》1995,12(5):632-638
Contact of mononuclear human leukocytes with cellulose dialysis membranes may result in complement-independent cell activation, i.e. enhanced synthesis of cytokines, prostaglandins and an increase in 2-microglobulin synthesis. Cellular contact activation is specifically inhibited by the monosaccharidel-fucose suggesting that dialysis membrane associatedl-fucose residues are involved in leukocyte activation. In this study we have detected and quantitatedl-fucose on commercially-available cellulose dialysis membranes using two approaches. A sensitive enzymatic fluorescence assay detectedl-fucose after acid hydrolysis of flat sheet membranes. Values ranged from 79.3±3.6 to 90.2±5.0 pmol cm–2 for Hemophan® or Cuprophan® respectively. Enzymatic cleavage of terminal -l-fucopyranoses with -l-fucosidase yielded 7.7±3.3 pmoll-fucose per cm2 for Cuprophan. Enzymatic hydrolysis of the synthetic polymer membranes AN-69 and PC-PE did not yield detectable amounts ofl-fucose. In a second approach, binding of the fucose specific lectins ofLotus tetragonolobus andUlex europaeus (UEAI) demonstrated the presence of biologically accessiblel-fucose on the surface of cellulose membranes. Specific binding was observed with Cuprophan®, and up to 2.6±0.3 pmoll-fucose per cm2 was calculated to be present from Langmuir-type adsorption isotherms. The data presented are in line with the hypothesis that surface-associatedl-fucose residues on cellulose dialysis membranes participate in leukocyte contact activation. 相似文献
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Regina Himmelspach Peter Nick Eberhard Schäfer Bruno Ehmann 《The Plant journal : for cell and molecular biology》1997,12(6):1299-1310
The cytosolic chaperonin containing TCP-1 (CCT) is known to keep fold cytoskeletal proteins and is involved in the proper organization of the cytoskeleton. These studies are based on the assumption that growth responses linked to structural rearrangement of the plant cytoskeleton include the action of CCT and the need for newly synthesized tubulin. The presence of the α- and ɛ- subunits of CCT was investigated in soluble fractions of protein extracts from maize mesocotyls and coleoptiles at distinct growth stages. The CCT-subunits, tubulins and actin decreased in the coleoptile in response to far-red light. In addition, independent from light treatment, the amount of CCTɛ abundance declined with age in coleoptiles and mesocotyls between 2 and 4.5 days after sowing. In contrast to CCTɛ, no significant light regulation of CCTα was found in the mesocotyl. In two day old, light-grown rapidly elongating coleoptiles part of the CCTα subunit and the bulk of actin and tubulin was found shifted into fractions of high molecular weight complexes when compared to slowly elongating, dark grown coleoptiles. In 4.5 day old, etiolated and elongating coleoptiles, part of both CCT-subunits and cytoskeleton proteins were found in fractions of high molecular weight. A complete disappearance of these polypeptides was observed in old far-red irradiated growth-arrested coleoptiles. CCTɛ was found to be co-localized to microtubular structures and to the nucleus. We conclude from our data that abundance of CCT-subunits in soluble extracts is dependent on age and light treatment, but independent from the growth stage of mesocotyl and coleoptile. 相似文献
50.