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排序方式: 共有1699条查询结果,搜索用时 15 毫秒
81.
Anna Schorcht Christopher A. Cottrell Pavel Pugach Rajesh P. Ringe Alvin X. Han Joel D. Allen Tom L. G. M. van den Kerkhof Gemma E. Seabright Edith E. Schermer Thomas J. Ketas Judith A. Burger Jelle van Schooten Celia C. LaBranche Gabriel Ozorowski Natalia de Val Daniel L. V. Bader Hanneke Schuitemaker Colin A. Russell David C. Montefiori Marit J. van Gils Max Crispin P. J. Klasse Andrew B. Ward John P. Moore Rogier W. Sanders 《Journal of virology》2022,96(1)
82.
David Wragg Elizabeth A. J. Cook Perle Latr de Lat Tatjana Sitt Johanneke D. Hemmink Maurine C. Chepkwony Regina Njeru E. Jane Poole Jessica Powell Edith A. Paxton Rebecca Callaby Andrea Talenti Antoinette A. Miyunga Gideon Ndambuki Stephen Mwaura Harriet Auty Oswald Matika Musa Hassan Karen Marshall Timothy Connelley Liam J. Morrison B. Mark deC. Bronsvoort W. Ivan Morrison Philip G. Toye James G. D. Prendergast 《PLoS genetics》2022,18(4)
East Coast fever, a tick-borne cattle disease caused by the Theileria parva parasite, is among the biggest natural killers of cattle in East Africa, leading to over 1 million deaths annually. Here we report on the genetic analysis of a cohort of Bos indicus (Boran) cattle demonstrating heritable tolerance to infection with T. parva (h2 = 0.65, s.e. 0.57). Through a linkage analysis we identify a 6 Mb genomic region on bovine chromosome 15 that is significantly associated with survival outcome following T. parva exposure. Testing this locus in an independent cohort of animals replicates this association with survival following T. parva infection. A stop gained variant in a paralogue of the FAF1 gene in this region was found to be highly associated with survival across both related and unrelated animals, with only one of the 20 homozygote carriers (T/T) of this change succumbing to the disease in contrast to 44 out of 97 animals homozygote for the reference allele (C/C). Consequently, we present a genetic locus linked to tolerance of one of Africa’s most important cattle diseases, raising the promise of marker-assisted selection for cattle that are less susceptible to infection by T. parva. 相似文献
83.
Jos Antonio García-Espinoza Jos Francisco Muoz-Valle Mariel García-Chagolln Jorge Hernndez-Bello Claudia Azucena Palafox-Snchez Erika Fabiola Lpez-Villalobos Gabriela Athziri Snchez-Zuno Gloria Esther Martínez-Bonilla Sergio Cerpa-Cruz Francisco Josue Carrillo-Ballesteros Edith Oregon-Romero 《Current issues in molecular biology》2022,44(2):764
Background: Primary Sjögren’s syndrome (pSS) is a systemic autoimmune disease, which affects exocrine glands. T cell activation is a trigger mechanism in the immune response. Hyperreactivity of T cells and antibody production are features in pSS. ICOS can be critical in the pathogenesis of pSS. Methods: A total of 134 pSS patients and 134 control subjects (CS) were included. Genotyping was performed by PCR-RFLP. ICOS mRNA expression was quantified by real-time PCR, and CD4+ ICOS+ T cells were determined by flow cytometry. Results: The ICOS IVS1 + 173 T>C polymorphisms were not associated with susceptibility to pSS (p = 0.393, CI = 0.503–1.311). However, the c.1624 C>T polymorphism was associated with a reduction in the risk of development of pSS (p = 0.015, CI = 0.294–0.884). An increase in ICOS mRNA expression in patients was observed (3.7-fold). Furthermore, pSS patients showed an increase in membranal-ICOS expression (mICOS). High expression of mICOS (MFI) was associated with lymphocytic infiltration. Conclusions: The IVS1 + 173 polymorphism is not a genetic marker for the development of pSS, while c.1624 T allele was associated with a low risk. However, elevated mICOS expression in pSS patients with high lymphocytic infiltration was found. ICOS may have an important role in the immunopathogenesis of pSS and should be analyzed in T cell subsets in pSS patients as a possible disease marker. 相似文献
84.
Jacoby Steven C.; Gagnon Edith; Caron Luc; Chang John; Isenring Paul 《American journal of physiology. Cell physiology》1999,277(4):C684
Mercury alters thefunction of proteins by reacting with cysteinyl sulfhydryl(SH) groups. Theinorganic form (Hg2+) is toxicto epithelial tissues and interacts with various transport proteinsincluding the Na+ pump andCl channels. In this study,we determined whether theNa+-K+-Clcotransporter type 1 (NKCC1), a major ion pathway in secretory tissues,is also affected by mercurial substrates. To characterize theinteraction, we measured the effect ofHg2+ on ion transport by thesecretory shark and human cotransporters expressed in HEK-293 cells.Our studies show that Hg2+inhibitsNa+-K+-Clcotransport, with inhibitor constant(Ki) values of25 µM for the shark carrier (sNKCC1) and 43 µM for thehuman carrier. In further studies, we took advantage of speciesdifferences in Hg2+ affinity toidentify residues involved in the interaction. An analysis ofhuman-shark chimeras and of an sNKCC1 mutant(Cys-697Leu) reveals that transmembrane domain 11 plays an essential role in Hg2+binding. We also show that modification of additionalSH groups by thiol-reactingcompounds brings about inhibition and that the binding sites are notexposed on the extracellular face of the membrane. 相似文献
85.
Recent medical advances have made it possible for babies to survive premature birth at increasingly earlier developmental stages. This population requires costly and sophisticated medical care to address the problems associated with immaturity of the respiratory system. In addition to pulmonary complications, respiratory instability and apnea reflecting immaturity of the respiratory control system are major causes of hospitalization and morbidity in this highly vulnerable population. These medical concerns, combined with the curiosity of physiologists, have contributed to the expansion of research in respiratory neurobiology. While most researchers working in this field commonly use rodents as an animal model, recent research using in vitro brainstem preparation from bullfrogs (Rana catesbeiana) have revealed the technical advantages of this animal model, and shown that the basic principles underlying respiratory control and its ontogeny are very similar between these two groups of vertebrates. The present review highlights the recent advances in the area of research with a focus on intermittent (episodic) breathing and the role of serotonergic and GABAergic modulation of respiratory activity during development. 相似文献
86.
Landegren U Schallmeiner E Nilsson M Fredriksson S Banér J Gullberg M Jarvius J Gustafsdottir S Dahl F Söderberg O Ericsson O Stenberg J 《Journal of molecular recognition : JMR》2004,17(3):194-197
Procedures and reagents are needed to specifically detect all the macromolecules that are being identified in the course of genome projects. We discuss how this challenge may be met using a set of ligation-based reagents termed padlock probes and proximity ligation probes. These probes include elements with affinity for specific nucleic acid and protein molecules, respectively, along with unique identifier DNA sequence elements that encode the identity of the recognized target molecules. The information content of DNA strands that form in the detection reactions are recorded after amplification, allowing the recognized target molecules to be identified. The procedures permit highly specific solution-phase or localized analyses of large sets of target molecules as required in future molecular analyses. 相似文献
87.
88.
This is the story of how we started studying the green bands seen on SDS-polyacrylamide gels of thylakoid membranes dissociated with the non-ionic detergent beta-octyl-D-glucopyranoside. We explain some of the complications we and other workers encountered along the pathway to untangling the chlorophyll-protein complexes of higher plants, and give a concise summary of the complexes, their polypeptides and their genes. 相似文献
89.
Expression and characterization of melanin-concentrating hormone receptors on mammalian cell lines 总被引:4,自引:0,他引:4
The neuropeptide melanin-concentrating hormone (MCH) is expressed in central and peripheral tissues where it participates in the complex network regulating energy homeostasis as well as in other physiologically important functions. Two MCH receptor subtypes, MCH-R1 and MCH-R2, have been cloned which signal through activation of Gi/o/q proteins and hence regulate different intracellular signals, such as inhibition of cAMP formation, stimulation of IP3 production, increase in intracellular free Ca2+ and/or activation of MAP kinases. Most of the data were obtained with cell systems heterologously expressing either of the MCH receptors. Fewer reports exist on studies with cell lines which endogenously express MCH receptors. Here, we describe human and other mammalian cell lines with which MCH receptor activation can be studied under "natural" conditions and we summarize the characteristics and signaling pathways of the MCH receptors in the different cell systems. 相似文献
90.
The two membrane segments of leader peptidase partition one by one into the lipid bilayer via a Sec/YidC interface
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We have addressed the mechanism of insertion of both transmembrane segments (TMs) of leader peptidase, a double-spanning protein, into the Escherichia coli inner membrane. Using photo-crosslinking, the first TM (H1) was shown to insert at a Sec-translocon/YidC interface in a fixed orientation. H1 lost its contacts with the Sec-translocon and gained access to lipids near YidC soon after complete exposure outside the ribosome. Following lipid integration, it moved away from the Sec/YidC insertion site. The second TM (H2) inserted and interacted with SecY and YidC in a similar transient fashion. The data are consistent with a linear integration model in which the TMs of polytopic inner membrane proteins move one by one from a Sec/YidC insertion site into the lipid bilayer. We propose that YidC assists the lipid partitioning of single TMs. 相似文献