scholarly journals Structural mechanisms of inflammasome assembly

FEBS Journal ◽  
2014 ◽  
Vol 282 (3) ◽  
pp. 435-444 ◽  
Author(s):  
Alvin Lu ◽  
Hao Wu
Keyword(s):  
Structural Mechanisms

scholarly journals Built to Last: Functional and Structural Mechanisms in the Moth Olfactory Network Mitigate Effects of Neural Injury

2021 ◽  
Vol 11 (4) ◽  
pp. 462
Author(s):  
Charles B. Delahunt ◽  
Pedro D. Maia ◽  
J. Nathan Kutz
Keyword(s):  
Brain Injuries ◽  
Hebbian Learning ◽  
Neuronal Damage ◽  
Neural Systems ◽  
Network Motifs ◽  
Neural Firing ◽  
Neural Injury ◽  
Axonal Pathology ◽  
Structural Mechanisms ◽  
Axonal Swellings

Most organisms suffer neuronal damage throughout their lives, which can impair performance of core behaviors. Their neural circuits need to maintain function despite injury, which in particular requires preserving key system outputs. In this work, we explore whether and how certain structural and functional neuronal network motifs act as injury mitigation mechanisms. Specifically, we examine how (i) Hebbian learning, (ii) high levels of noise, and (iii) parallel inhibitory and excitatory connections contribute to the robustness of the olfactory system in the Manduca sexta moth. We simulate injuries on a detailed computational model of the moth olfactory network calibrated to data. The injuries are modeled on focal axonal swellings, a ubiquitous form of axonal pathology observed in traumatic brain injuries and other brain disorders. Axonal swellings effectively compromise spike train propagation along the axon, reducing the effective neural firing rate delivered to downstream neurons. All three of the network motifs examined significantly mitigate the effects of injury on readout neurons, either by reducing injury’s impact on readout neuron responses or by restoring these responses to pre-injury levels. These motifs may thus be partially explained by their value as adaptive mechanisms to minimize the functional effects of neural injury. More generally, robustness to injury is a vital design principle to consider when analyzing neural systems.

scholarly journals Structural Mechanisms of Gating in Ionotropic Glutamate Receptors

Biochemistry ◽  
2017 ◽  
Vol 57 (3) ◽  
pp. 267-276 ◽  
Author(s):  
Edward C. Twomey ◽  
Alexander I. Sobolevsky
Keyword(s):  
Glutamate Receptors ◽  
Ionotropic Glutamate Receptors ◽  
Structural Mechanisms

scholarly journals Comparative analysis of plant isochorismate synthases reveals structural mechanisms underlying their distinct biochemical properties

2018 ◽  
Vol 38 (2) ◽  
Author(s):  
Shohei Yokoo ◽  
Seiya Inoue ◽  
Nana Suzuki ◽  
Naho Amakawa ◽  
Hidenori Matsui ◽  
...  
Keyword(s):  
Biochemical Properties ◽  
Stress Conditions ◽  
The Other ◽  
Protein Accumulation ◽  
Transcriptional Level ◽  
Multiple Sequence ◽  
Primary And Secondary Metabolites ◽  
Transit Peptides ◽  
Alignment Analysis ◽  
Structural Mechanisms

Isochorismate synthase (ICS) converts chorismate into isochorismate, a precursor of primary and secondary metabolites including salicylic acid (SA). SA plays important roles in responses to stress conditions in plants. Many studies have suggested that the function of plant ICSs is regulated at the transcriptional level. In Arabidopsis thaliana, the expression of AtICS1 is induced by stress conditions in parallel with SA synthesis, and AtICS1 is required for SA synthesis. In contrast, the expression of NtICS is not induced when SA synthesis is activated in tobacco, and it is unlikely to be involved in SA synthesis. Studies on the biochemical properties of plant ICSs are limited, compared with those on transcriptional regulation. We analyzed the biochemical properties of four plant ICSs: AtICS1, NtICS, NbICS from Nicotiana benthamiana, and OsICS from rice. Multiple sequence alignment analysis revealed that their primary structures were well conserved, and predicted key residues for ICS activity were almost completely conserved. However, AtICS1 showed much higher activity than the other ICSs when expressed in Escherichia coli and N. benthamiana leaves. Moreover, the levels of AtICS1 protein expression in N. benthamiana leaves were higher than the other ICSs. Construction and analysis of chimeras between AtICS1 and OsICS revealed that the putative chloroplast transit peptides (TPs) significantly affected the levels of protein accumulation in N. benthamiana leaves. Chimeric and point-mutation analyses revealed that Thr531, Ser537, and Ile550 of AtICS1 are essential for its high activity. These distinct biochemical properties of plant ICSs may suggest different roles in their respective plant species.

scholarly journals Surface Purity Effect on Irregularities of Changes in Deformation Texture of Zr-2.5% Nb Alloy

2021 ◽  
Keyword(s):  
Texture Coefficient ◽  
Cold Deformation ◽  
Deformation Texture ◽  
Longitudinal Rolling ◽  
Near Surface ◽  
Pole Figures ◽  
Integral Characteristics ◽  
Surface Purity ◽  
Textural Changes ◽  
Structural Mechanisms

This work is a continuation of a series of works on the study of regularities and structural mechanisms of changes in characteristics of crystallographic texture during cold deformation of plates made of Zr2.5%Nb alloy. Effects of influence of surface cleanliness of the plates on the textural regularities during their rolling were investigated. For this, longitudinal fragments of the tube Æ15.0´1.5 mm² were used, flattened, annealed at 580°C in a vacuum of 1.5...3.0 Pa and rolled along the axis of the original tube with various degrees deformation up to 56%, which is likened to longitudinal rolling of plates. Techniques of maximally uniform straightening of tube fragments were used. An analysis of the results of studies of textural changes during cross rolling of plates, straightened from rings of the same tube and pretreated under similar conditions, is also carried out. To analyze the results, the method of inverse pole figures was used, which, in these studies, is distinguished by the possibility of achieving satisfactory accuracy in calculating the integral characteristics of texture. On this basis, the Kearns textural coefficient was calculated along the normal to the plates’ plane. Corrections were introduced for texture dissimilarity along the thickness of the plates, which is caused by the unbending of the preliminary blanks. Additionally, the analysis of texture distributions was carried out using original techniques. According to the results obtained – as a result of X-ray measuring from the plates’ surface – oscillations of the course of changes in the texture coefficient were revealed. This is associated with an alternating process of relaxation of residual stresses during deformation. It has been established that this effect is initiated from the near-surface regions, is associated with a near-surface impurity, and in some cases can penetrate to a considerable depth of the plates. The twinning nature of such regularities is confirmed and active systems of twins are noted.

scholarly journals Biochemical and structural mechanisms of regulation of Arf GTPases by endocytic GEFs (LB259)

2014 ◽  
Vol 28 (S1) ◽  
Author(s):  
Mahel Zeghouf ◽  
Kaheina Aizel ◽  
Valérie Biou ◽  
Dominique Padovani ◽  
Jacqueline Cherfils
Keyword(s):  
Arf Gtpases ◽  
Structural Mechanisms

scholarly journals ONE DONOR EGG AND “A DOLLOP OF LOVE”: THE BANAL AMBIGUITIES OF EGG DONATION ADVERTISING ON FACEBOOK

2020 ◽  
Author(s):  
Tanya Kant ◽  
Elizabeth Reed
Keyword(s):  
User Interface ◽  
Textual Analysis ◽  
Assisted Reproductive Technologies ◽  
Reproductive Technologies ◽  
Egg Donation ◽  
Targeted Advertising ◽  
Structural Rigidity ◽  
Donor Egg ◽  
Targeted Marketing ◽  
Structural Mechanisms

Using textual analysis of 28 adverts for egg donation, sharing, and freezing drawn from Facebook’s Ad Library archive, we consider what forms of motherhood, kinship, and sociality are promised through targeted advertisements for Assisted Reproductive Technologies (ARTs) on Facebook. We seek to understand (1) how egg donation, sharing and freezing adverts by ART providers represent the women they expect to use their services; (2) how the meaning of these representations is changed by their delivery through algorithmically targeted marketing; and (3) what imaginative, genealogical, and relational possibilities are foreclosed or endorsed in the delivery of these adverts to algorithmically anticipated “fertile females”. Through textual analysis we seek to understand the forms of potential “life” that are present in the advertisements. We consider the representations of egg donation, identify a banal ambiguity in promised post-feminist kinship, and identify the selected families-in-making which might be created by ART. We combine this with a critical interrogation of how and why these adverts are targeted and delivered to certain demographics of algorithmically anticipated Facebook users. The opacity and structural rigidity of Facebook’s targeted advertising systems – structural mechanisms that are binaric in back-end databases and yet “lively” at the point of the user interface - require that we interrogate both media text and computational delivery mechanisms to meaningfully understand what forms of “life” are promised by gender-targeted ART. The genealogical possibility offered through ART is represented with banal ambiguity wherein potentially disruptive arrangements of kinship are derisked by an overarching narrative of simplicity and sameness.

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