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31.
A linkage group of five DNA markers on human chromosome 10 总被引:3,自引:0,他引:3
Five chromosome 10 DNA markers (D10S1, D10S3, D10S4, D10S5, and RBP3) were typed in five large pedigrees with multiple endocrine neoplasia type 2A (MEN-2A) and in five non-MEN-2A pedigrees. Linkage analyses showed that these loci and the locus for MEN-2A (MEN2A) are in one linkage group spanning at least 70 cM. The order of the marker loci is RBP3-D10S5-D10S3-D10S1-D10S4, with interlocus recombination frequencies of 7, 13-19, 19, and 19%, respectively, all on the same side of MEN2A. Analyses of sex-specific recombination frequencies indicated no significant differences between males and females for any of the map intervals studied. Previous localization of D10S5 and RBP3 to the proximal region of the long arm and the pericentric region, respectively, comparison of results with other studies, and our preliminary results with other chromosome 10 markers suggest that the D10S4 end of the map extends into the long arm. Our linkage map has been constructed using only two- and three-locus analyses. It will be possible to combine our results with those of other groups to construct a more detailed and accurate genetic map of chromosome 10. 相似文献
32.
Stefan Jansson Eran Pichersky Roberto Bassi Beverley R. Green Masahiko Ikeuchi Anastasios Melis David J. Simpson Michael Spangfort L. Andrew Staehelin J. Philip Thornber 《Plant Molecular Biology Reporter》1992,10(3):242-253
We propose a nomenclature for the genes encoding the chlorophylla/b-binding proteins of the light-harvesting complexes of photosystem I and II. The genes encoding LHC I and LHC II polypeptides
are namedLhca1 throughLhca4 andLhcb1 throughLhcb6, respectively. The proposal follows the general format recommended by the Commision on Plant Gene Nomenclature. We also present
a table for the conversion of old gene names to the new nomenclature. 相似文献
33.
Expression of mRNA encoding basic fibroblast growth factor (bFGF) in bovine corpora lutea and cultured luteal cells. 总被引:2,自引:0,他引:2
A radiolabelled cRNA was synthesized using a 1.4 kb cDNA complementary to mRNA encoding bovine basic fibroblast growth factor (bFGF) as a template, and used as a probe to investigate the expression of mRNA encoding bFGF in bovine ovarian tissue, and luteal cells in primary culture. Northern analysis of poly(A +)RNA prepared from follicles and corpora lutea of various stages revealed a major mRNA species of 7 kb in corpora lutea of all stages, the amount of which was higher late in the luteal phase. No hybridizable message was detectable in follicles of any size. When luteal cells were established in primary culture, expression of the 7 kb mRNA species was maintained. This expression was increased markedly when cells were treated with LH/hCG or Bt2cAMP. Prostaglandin F-2 alpha treatment caused a marked decrease in the basal content of this 7 kb mRNA, and also severely impaired the ability of LH to stimulate this expression. 相似文献
34.
K M Simpson K N Dileepan D J Stechschulte 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1991,197(1):44-48
Peptides such as parathyroid hormone (PTH), somatostatin, and gastrin have been reported to stimulate mast cell mediator release. Preincubation of rat serosal mast cells with synthetic 1-34 bovine parathyroid hormone (1-34bPTH) significantly enhanced antigen-induced 5-hydroxytryptamine (5-HT) release. Enhancement of 5-HT release by 1-34bPTH was dose dependent between 5 and 2000 nM. In the absence of antigen, mean net 5-HT release was less than 1% when naive or passively sensitized mast cells were incubated with 1000 nM 1-34bPTH for time intervals up to 90 min. These findings indicate that 1-34bPTH, at relatively low concentration, potentiates antigen-induced 5-HT release from mast cells. 相似文献
35.
G. Kochert T. Halward W. D. Branch C. E. Simpson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,81(5):565-570
Summary RFLP variability was studied in eight U.S. peanut cultivars, representing the four market types, and in 14 wild Arachis species accessions, using random genomic clones from a PstI library. Very low levels of RFLP variability were found among the allotetraploids, which included the U.S. cultivars and Arachis monticola, a wild species. The diploid wild species were very diverse, however. RFLP patterns of the allotetraploids were more complex than the diploids, and the two constituent genomes could usually be distinguished. On the basis of RFLP band sharing, A. ipaensis, A. duranensis, and A. spegazzinii appeared most closely related to the diploid progenitor species of the allotetraploids. A dendrogram of relationships among the diploid wild species was constructed based on band sharing. 相似文献
36.
Gerardo Argüello Enrique García-Hernández Mireya Sánchez Patricio Gariglio Luis Herrera-Estrella June Simpson 《The Plant journal : for cell and molecular biology》1992,2(3):301-309
Two protein factors binding to the regulatory region of the pea chlorophyl a/b binding protein gene AB80 have been identified. One of these factors is found only in green tissue but not in etiolated or root tissue. The second factor (denominated ABF-2) binds to a DNA sequence element that contains a direct heptamer repeat TCTCAAA. It was found that presence of both of the repeats is essential for binding. ABF-2 is present in both green and etiolated tissue and in roots and factors analogous to ABF-2 are present in several plant species. Computer analysis showed that the TCTCAAA motif is present in the regulatory region of several plant genes. 相似文献
37.
Richard K. Simpson Jr. Claudia S. Robertson J. Clay Goodman 《Neurochemical research》1991,16(1):89-94
The present study used microdialysis techniques in an intact rabbit model to measure the release of amino acids within the lumbar spinal cord in response to transcranial electrical stimulation. Dialysis samples from the extracellular space were obtained over a stimulation period of 90 minutes and were examined using high pressure liquid chromatography. Neuronal excitation was verified by recerding corticomotor evoked potentials (CMEPs) from the spinal cord. A significant increase in the release of glycine and taurine compared to sham animals was measured after 90 minutes of transcranial stimulation. Glutamate and aspartate release was not significantly elevated. GABA concentrations were consistently low. CMEP components repeatedly showed adequate activation of descending fiber pathways and segmental interneuron pools during dialysis sampling. Since glycine, and to a lesser extent taurine, have been shown to inhibit motor neuron activity and are closely associated with segmental interneuron pools, suprasegmental modulation of motor activity may be, in part, through these inhibitory amino acid neurotransmitters in the rabbit lumbar spinal cord. 相似文献
38.
A rabbit antiserum to the C-terminus of the putative brain amyloid precursor was used to probe Western blots of tissue proteins separated by SDS-PAGE. The antiserum specifically labelled a protein of approx. 70 kDa in the Tris buffer-soluble fraction of brain samples from rat, Alzheimer subjects, cases of young and old Down's syndrome, and age-matched controls. The 70 kDa protein was present in low concentrations in human liver and kidney, and was undetectable in human skeletal muscle. The 70 kDa protein may be a metabolite of the amyloid precursor. 相似文献
39.
T Ratajczak M J Brockway R H?hnel R L Moritz R J Simpson 《Biochemical and biophysical research communications》1988,156(1):116-124
Tryptic peptides generated from bovine estrogen receptor have been fractionated and purified using microbore column high performance liquid chromatography. Sequence analysis performed on six of these peptides, derived from diverse structural regions of the receptor protein, yielded 73 unique assignments corresponding to approximately 12% of the molecule. The amino acid sequences of these peptides displayed a high degree of similarity with corresponding sequences from estrogen receptors of mammalian origin, but were only moderately conserved in receptors from non-mammalian species. The sequenced residues of one tryptic peptide, positioned in the estrogen binding domain, were fully conserved in all estrogen receptors. 相似文献
40.
Studies on the role of transferrin and endocytosis in the uptake of Fe3+ from Fe-nitrilotriacetate by mouse duodenum 总被引:2,自引:0,他引:2
R J Simpson K R Osterloh K B Raja S D Snape T J Peters 《Biochimica et biophysica acta》1986,884(1):166-171
Addition of iron-binding proteins (human serum transferrin, mouse serum transferrin, human lactoferrin) to the luminal fluid in tied-off segments of mouse intestine in vivo led to reduced 59Fe3+ absorption from 59Fe3+-nitrilotriacetate when compared to 59Fe3+-nitrilotriacetate alone. Assay of transferrin in luminal fluid from tied segments revealed only trace amounts of immunoreactivity. The levels of luminal transferrin are unaltered in chronic hypoxia where iron absorption is significantly enhanced. Studies in vitro revealed that NH4Cl, dansylcadavarine, para-chloromercuribenzoate and trinitrobenzenesulphonate have no effect on initial 59Fe3+ uptake rates from 59Fe3+-nitrilotriacetate, while N-ethylmaleimide (1 mM) caused a 40% inhibition. In vivo 59Fe3+ uptake was unaffected by preincubation of tied-off segments with colchicine (5 mM) for up to 2 h. These results suggest that receptor-mediated endocytosis of transferrin is not a significant mechanism in the uptake of luminal Fe3+ by mouse duodenum. 相似文献