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71.
72.
Induction of an interleukin-1 receptor (IL-1R) on monocytic cells. Evidence that the receptor is not encoded by a T cell-type IL-1R mRNA 总被引:9,自引:0,他引:9
M K Spriggs P J Lioubin J Slack S K Dower U Jonas D Cosman J E Sims J Bauer 《The Journal of biological chemistry》1990,265(36):22499-22505
Primary human monocytes and the human monocytic cell line THP-1 were induced to express receptors for interleukin-1 alpha (IL-1 alpha) and IL-1 beta. Treatment of primary monocytes with dexamethasone resulted in a 10-fold increase in receptor number over untreated cells, to approximately 2,000 receptors/cell. Treatment of THP-1 cells with phorbol ester followed by prostaglandin E2 and dexamethasone resulted in the expression of approximately 30,000 receptors/cell. Competitive binding assays on THP-1 cells showed that both IL-1 alpha and IL-1 beta bind to the same receptor. The monocyte IL-1R is significantly smaller (63 kDa) than the T cell IL-1R (80 kDa) and is immunologically distinct. However, induction of monocytes and monocytic cell lines leads to the appearance of an abundant mRNA of approximately 5,000 bases which hybridizes to a cDNA probe from the T cell-type IL-1R. Sequence data obtained from a cDNA clone of this mRNA indicate that the message is identical to the T cell IL-1R mRNA throughout the coding region. A smaller mRNA, also homologous to the T cell IL-1R mRNA, accumulated in induced THP-1 cells and has a shorter 3'-untranslated region than the larger. Data are presented which suggest that neither form of this message encodes the 63-kDa IL-1R, but rather that this protein is the product of a separate nonhomologous mRNA. 相似文献
73.
Plastids isolated from maturing, nongreen safflower (Carthamus tinctorius L.) cotyledons yielded unesterified fatty acids as the predominant product of fatty-acid synthesis from [1-14C]acetate. Exogenous reduced pyridine nucleotides were not required for this synthesis, but [1-14C]acetate incorporation was absolutely dependent on addition of ATP. Linseed (Linum usitatissimum L.) cotyledons are green during development and plastids isolated from them resembled leaf chloroplasts with developed grana. In contrast to the safflower plastids, those from linseed were able to carry out fatty-acid synthesis at low irradiances without the addition of either pyridine nucleotides or ATP. Intact linseed cotyledons were capable of net photosynthesis at rates up to 95 mol·mg-1 chlorophyll·h-1. However, the low-light environment inside the linseed capsule (approx. 15% of external) means that photosynthesis will not contribute appreciably to the carbon economy of the developing seed and its main role may be to supply cofactors for fatty-acid synthesis.Abbreviations ACP
acyl carrier protein
- DHAP
dihydroxyacetone phosphate
- PC
phosphatidylcholine
- PEP
phosphoenolpyruvate
- UFA
unesterified fatty acids 相似文献
74.
75.
Teri J. Slack Wanqing Li Dashuang Shi John B. McArthur Gengxiang Zhao Yanhong Li An Xiao Zahra Khedri Hai Yu Yang Liu Xi Chen 《Bioorganic & medicinal chemistry》2018,26(21):5751-5757
Sialidases or neuraminidases are enzymes that catalyze the cleavage of terminal sialic acids from oligosaccharides and glycoconjugates. They play important roles in bacterial and viral infection and have been attractive targets for drug development. Structure-based drug design has led to potent inhibitors against neuraminidases of influenza A viruses that have been used successfully as approved therapeutics. However, selective and effective inhibitors against bacterial and human sialidases are still being actively pursued. Guided by crystal structural analysis, several derivatives of 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (Neu5Ac2en or DANA) were designed and synthesized as triazole-linked transition state analogs. Inhibition studies revealed that glycopeptide analog E-(TriazoleNeu5Ac2en)-AKE and compound (TriazoleNeu5Ac2en)-A were selective inhibitors against Vibrio cholerae sialidase, while glycopeptide analog (TriazoleNeu5Ac2en)-AdE selectively inhibited Vibrio cholerae and A. ureafaciens sialidases. 相似文献
76.
Mapping and marker-assisted selection for a gene for extreme resistance to potato virus Y 总被引:7,自引:1,他引:6
J. H. Hämäläinen K. N. Watanabe J. P. T. Valkonen A. Arihara R. L. Plaisted E. Pehu L. Miller S. A. Slack 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(2):192-197
The chromosomal location of the major gene Ry
adg
controlling extreme resistance to potato virus Y (PVY) in Solanum tuberosum subsp. andigena was identified by RFLP analysis of a diploid potato population. A total of 64 tomato and potato RFLP markers were screened
with the bulked segregant analysis (BSA) on segregants extremely resistant, hypersensitive or susceptible to PVY. Four markers
TG508, GP125, CD17 and CT168 at the proximal end of chromosome XI showed close linkage with extremely resistant phenotypes.
TG508 was identified as the closest marker linked with the Ry
adg
locus with the maximum map distance estimated as 2.0 cM. The 4 markers linked with the Ry
adg
locus were tested on independent tetraploid and diploid potato clones and were subsequently found useful for marker-assisted
selection for plants containing Ry
adg
.
Received: 5 July 1996 / Accepted: 19 July 1996 相似文献
77.
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80.
NM Kouyoumdzian NL Rukavina Mikusic G Cao MR Choi SL Della Penna BE Fernández 《Biotechnic & histochemistry》2016,91(8):510-521
We studied the effects of tempol, an oxygen radical scavenger, on hydrosaline balance in rats with acute sodium overload. Male rats with free access to water were injected with isotonic (control group) or hypertonic saline solution (0.80 mol/l NaCl) either alone (Na group) or with tempol (Na-T group). Hydrosaline balance was determined during a 90 min experimental period. Protein expressions of aquaporin 1 (AQP1), aquaporin 2 (AQP2), angiotensin II (Ang II) and endothelial nitric oxide synthase (eNOS) were measured in renal tissue. Water intake, creatinine clearance, diuresis and natriuresis increased in the Na group. Under conditions of sodium overload, tempol increased plasma sodium and protein levels and increased diuresis, natriuresis and sodium excretion. Tempol also decreased water intake without affecting creatinine clearance. AQP1 and eNOS were increased and Ang II decreased in the renal cortex of the Na group, whereas AQP2 was increased in the renal medulla. Nonglycosylated AQP1 and eNOS were increased further in the renal cortex of the Na-T group, whereas AQP2 was decreased in the renal medulla and was localized mainly in the cell membrane. Moreover, p47-phox immunostaining was increased in the hypothalamus of Na group, and this increase was prevented by tempol. Our findings suggest that tempol causes hypernatremia after acute sodium overload by inhibiting the thirst mechanism and facilitating diuresis, despite increasing renal eNOS expression and natriuresis. 相似文献