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111.
112.
Dong A Xu X Edwards AM;Midwest Center for Structural Genomics;Structural Genomics Consortium Chang C Chruszcz M Cuff M Cymborowski M Di Leo R Egorova O Evdokimova E Filippova E Gu J Guthrie J Ignatchenko A Joachimiak A Klostermann N Kim Y Korniyenko Y Minor W Que Q Savchenko A Skarina T Tan K Yakunin A Yee A Yim V Zhang R Zheng H Akutsu M Arrowsmith C Avvakumov GV Bochkarev A Dahlgren LG Dhe-Paganon S Dimov S Dombrovski L Finerty P Flodin S Flores A Gräslund S Hammerström M Herman MD Hong BS 《Nature methods》2007,4(12):1019-1021
We tested the general applicability of in situ proteolysis to form protein crystals suitable for structure determination by adding a protease (chymotrypsin or trypsin) digestion step to crystallization trials of 55 bacterial and 14 human proteins that had proven recalcitrant to our best efforts at crystallization or structure determination. This is a work in progress; so far we determined structures of 9 bacterial proteins and the human aminoimidazole ribonucleotide synthetase (AIRS) domain. 相似文献
113.
Tatiana B. Feldman Oleksandr I. Ivankov Alexander I. Kuklin Tatiana N. Murugova Marina A. Yakovleva Olga A. Smitienko Irina B. Kolchugina Adam Round Valentin I. Gordeliy Alexander V. Belushkin Mikhail A. Ostrovsky 《生物化学与生物物理学报:生物膜》2019,1861(10):183000
The supramolecular organization of the visual pigment rhodopsin in the photoreceptor membrane remains contentious. Specifically, whether this G protein-coupled receptor functions as a monomer or dimer remains unknown, as does the presence or absence of ordered packing of rhodopsin molecules in the photoreceptor membrane. Completely opposite opinions have been expressed on both issues. Herein, using small-angle neutron and X-ray scattering approaches, we performed a comparative analysis of the structural characteristics of the photoreceptor membrane samples in buffer, both in the outer segment of photoreceptor cells, and in the free photoreceptor disks. The average distance between the centers of two neighboring rhodopsin molecules was found to be ~5.8 nm in both cases. The results indicate an unusually high packing density of rhodopsin molecules in the photoreceptor membrane, but molecules appear to be randomly distributed in the membrane without any regular ordering. 相似文献
114.
Plant and Soil - Citrate secretion is a kind of typical strategy for plant against aluminum (Al) toxicity. However, the signaling process in Al-activated citrate secretion needs to be clarified.... 相似文献
115.
Jakovljevic Biljana Nikolic Turnic Tamara Jeremic Nevena Jeremic Jovana Bradic Jovana Ravic Marko Jakovljevic Vladimir Lj. Jelic Djordje Radovanovic Dragan Pechanova Olga Zivkovic Vladimir 《Molecular and cellular biochemistry》2019,453(1-2):111-119
Molecular and Cellular Biochemistry - Melatonin is a crucial neurohormone synthesized in the pineal gland that influences the physiology of animals. The molecular mechanism of norepinephrine... 相似文献
116.
Alexey Polonikov Larisa Rymarova Elena Klyosova Anastasia Volkova Iuliia Azarova Olga Bushueva Marina Bykanova Iuliia Bocharova Sergey Zhabin Mikhail Churnosov Vitaliy Laskov Maria Solodilova 《Journal of cellular biochemistry》2019,120(10):16467-16482
The present study investigated a joint contribution of matrix metalloproteinases (MMPs) genes to ischemic stroke (IS) development and analyzed interactions between MMP genes and genome-wide associated loci for IS. A total of 1288 unrelated Russians (600 IS patients and 688 healthy individuals) from Central Russia were recruited for the study. Genotyping of seven single nucleotide polymorphisms (SNPs) of MMP genes (rs1799750, rs243865, rs3025058, rs11225395, rs17576, rs486055, and rs2276109) and eight genome-wide associated loci for IS were done using Taq-Man–based assays and MALDI-TOF mass spectrometry iPLEX platform, respectively. Allele − 799T at rs11225395 of the MMP8 gene was significantly associated with a decreased risk of IS after adjustment for sex and age (OR = 0.82; 95%CI, 0.70-0.96; P = 0.016). The model-based multifactor dimensionality reduction method has revealed 21 two-order, 124 three-order, and 474 four-order gene-gene (G×G) interactions models meaningfully (Pperm < 0.05) associated with the IS risk. The bioinformatic analysis enabled establishing the studied MMP gene polymorphisms possess a clear regulatory potential and may be targeted by gene regulatory networks driving molecular and cellular pathways related to the pathogenesis of IS. In conclusion, the present study was the first to identify an association between polymorphism rs11225395 of the MMP8 gene and IS risk. The study findings also indicate that MMPs deserve special attention as a potential class of genes influencing the multistep mechanisms of cerebrovascular disease including atherosclerosis in cerebral arteries, acute cerebral artery occlusion as well as the ischemic injury of the brain and its recovery. 相似文献
117.
Gianfranco Biondi Olga Rickards Cristina Martinez-Labarga Tea Taraborelli Bianca Ciminelli Giorgio Gruppioni 《American journal of physical anthropology》1996,99(4):519-535
Genetic structure of the Berba of Benin was studied on the basis of biodemographic data and ABO, RH, MNS, KEL, JK, FY, ACP1, ADA, AK1, CA2, ESD, GLO1, G6PD, PGD, PGM1 (subtypes and thermostability), PGM2, PGP, SODA, HBα, HBβ, HBδ, BF, C3, and Hp gene frequencies. Comparisons were carried out with other populations of Benin and of sub-Sahara Africa. Correspondence analysis revealed genetic differentiation among the three main groups of populations who inhabit sub-Saharan Africa: Bushmen-Hottentots, Pygmies, and Negroes. The genetic differentiation of the Negroes in relation to their linguistic affiliation and geographic localization was evident. The first group included the populations belonging to the Bantoid subfamily of the Nigritic linguistic stock living in southern Africa; in the second subcluster the populations of central-eastern Africa were localized, and the third subcluster included the populations living in the West. © 1996 Wiley-Liss, Inc. 相似文献
118.
Regina Shebanova Natalia Nikitchina Nikita Shebanov Vladimir Mekler Konstantin Kuznedelov Egor Ulashchik Ruslan Vasilev Olga Sharko Vadim Shmanai Ivan Tarassov Konstantin Severinov Nina Entelis Ilya Mazunin 《Nucleic acids research》2022,50(2):1162
CRISPR RNAs (crRNAs) that direct target DNA cleavage by Type V Cas12a nucleases consist of constant repeat-derived 5′-scaffold moiety and variable 3′-spacer moieties. Here, we demonstrate that removal of most of the 20-nucleotide scaffold has only a slight effect on in vitro target DNA cleavage by a Cas12a ortholog from Acidaminococcus sp. (AsCas12a). In fact, residual cleavage was observed even in the presence of a 20-nucleotide crRNA spacer moiety only. crRNAs split into separate scaffold and spacer RNAs catalyzed highly specific and efficient cleavage of target DNA by AsCas12a in vitro and in lysates of human cells. In addition to dsDNA target cleavage, AsCas12a programmed with split crRNAs also catalyzed specific ssDNA target cleavage and non-specific ssDNA degradation (collateral activity). V-A effector nucleases from Francisella novicida (FnCas12a) and Lachnospiraceae bacterium (LbCas12a) were also functional with split crRNAs. Thus, the ability of V-A effectors to use split crRNAs appears to be a general property. Though higher concentrations of split crRNA components are needed to achieve efficient target cleavage, split crRNAs open new lines of inquiry into the mechanisms of target recognition and cleavage and may stimulate further development of single-tube multiplex and/or parallel diagnostic tests based on Cas12a nucleases. 相似文献
119.
Malte Jochum Lise Thouvenot Olga Ferlian Romy Zeiss Bernhard Klarner Ulrich Pruschitzki Edward A. Johnson Nico Eisenhauer 《Biology letters》2022,18(3)
Declining arthropod communities have recently gained a lot of attention, with climate and land-use change among the most frequently discussed drivers. Here, we focus on a seemingly underrepresented driver of arthropod community decline: biological invasions. For approximately 12 000 years, earthworms have been absent from wide parts of northern North America, but they have been re-introduced with dramatic consequences. Most studies investigating earthworm-invasion impacts focus on the belowground world, resulting in limited knowledge on aboveground-community changes. We present observational data on earthworm, plant and aboveground arthropod communities in 60 plots, distributed across areas with increasing invasion status (low, medium and high) in a Canadian forest. We analysed how earthworm-invasion status and biomass impact aboveground arthropod community abundance, biomass and species richness, and how earthworm impacts cascade across trophic levels. We sampled approximately 13 000 arthropods, dominated by Hemiptera, Diptera, Araneae, Thysanoptera and Hymenoptera. Total arthropod abundance, biomass and species richness declined significantly from areas of low to those with high invasion status, with reductions of 61, 27 and 18%, respectively. Structural equation models suggest that earthworms directly and indirectly impact arthropods across trophic levels. We show that earthworm invasion can alter aboveground multi-trophic arthropod communities and suggest that belowground invasions might be underappreciated drivers of aboveground arthropod decline. 相似文献
120.
Alzheimer''s disease (AD) pathology is characterized by loss of memory cognitive and behavioral deterioration. One of the hallmarks of AD is amyloid β (Aβ) plaques in the brain that consists of Aβ oligomers and fibrils. It is accepted that oligomers, particularly dimers, are toxic species that are produced extracellularly and intracellularly in membranes. It is believed that the disruption of membranes by polymorphic Aβ oligomers is the key for the pathology of AD. This is a first study that investigate the effect of polymorphic “α‐helix/random coil” and “fibril‐like” Aβ dimers on 1,2‐dioleoyl‐sn‐glycero‐3‐phosphocholine (DOPC) membrane. It has been found that the DOPC membrane promotes Aβ1–42 “fibril‐like” dimers and impedes Aβ1–42 “α‐helix/random coil” dimers. The N‐termini domains within Aβ1–42 dimers play a role in Aβ aggregation in membrane milieus. In addition, the aromatic π–π interactions (involving residues F19 and F20 in Aβ1–42) are the driving forces for the hydrophobic interactions that initiate the primary nucleation of polymorphic Aβ1–42 dimers within DOPC membrane. Finally, the DOPC bilayer membrane thickness is locally decreased, and it is disrupted by an embedded distinct Aβ1–42 dimer, due to relatively large contacts between Aβ1–42 monomers and the DOPC membrane. This study reveals insights into the molecular mechanisms by which polymorphic early‐stage Aβ1–42 dimers have distinct impacts on DOPC membrane. 相似文献