bluuebunny/crossref_metadata_2025_split huggingface dataset:
The structural basis of the Talin-KANK1 interaction that coordinates the actin and microtubule cytoskeletons at focal adhesions
Authors: Li X , Goult B.T , Ballestrem C , Zacharchenko T 
Published: February 2023

AbstractAdhesion between cells and the extracellular matrix (ECM) is mediated by heterodimeric (αβ) integrin receptors that are intracellularly linked to the contractile actomyosin machinery. One of the proteins that control this link is talin, which organises cytosolic signalling proteins into discrete complexes on β-integrin tails referred to as focal adhesions (FAs). The adapter protein KANK1 binds to talin in the region of FAs known as the adhesion belt. Here, we developed a novel crystallographic method to resolve the talin-KANK1 complex. This structure revealed that the talin binding KN motif of KANK1 has a novel fold, where a β-turn stabilises the α-helical region, explaining its specific interaction with talin R7 and high affinity. Single point mutants in KANK1 identified from the structure abolished the interaction and enabled us to examine KANK1 enrichment in the adhesion belt. Strikingly, in cells expressing a constitutively active form of vinculin that keeps the FA structure intact even in the presence of myosin inhibitors, KANK1 localises throughout the entire FA structure even when actomyosin tension is released. We propose a model whereby actomyosin forces on talin eliminate KANK1 from talin binding in the centre of FAs while retaining it at the adhesion periphery.
Interplay between a bacterial pathogen and its host in rainbow trout isogenic lines with contrasted susceptibility to Cold Water Disease
Authors: Lee Bo-Hyung , Quillet Edwige , Rigaudeau Dimitri , Dechamp Nicolas , Duchaud Eric , Bernardet Jean-François , Boudinot Pierre , Rochat Tatiana 
Published: February 2023

AbstractInfectious diseases are a major constraint on aquaculture. Genetic lines with different susceptibilities to diseases are useful models to identify resistance mechanisms to pathogens and to improve prophylaxis. Bacterial cold-water disease (BCWD) caused byFlavobacterium psychrophilumrepresents a major threat for freshwater salmonid farming worldwide. A collection of rainbow trout (Oncorhynchus mykiss) isogenic lines was previously produced from a French domestic population. Here, we compared BCWD resistance phenotypes using a subset of isogenic lines chosen for their contrasted susceptibilities toF. psychrophilum. We applied individual monitoring to document the infection process, including time-course quantification of bacteremia and innate immune response. Strikingly, BCWD resistance was correlated with a lower bacterial growth rate in blood. Several immune genes were expressed at higher levels in resistant fish regardless of infection: the Type II arginase (arg2), a marker for M2 macrophages involved in anti-inflammatory responses and tissue repair, and two Toll-like receptors (tlr2/tlr7), responsible for pathogen detection and inflammatory responses. This study highlights the importance of innate and intrinsic defense mechanisms in determining the outcome ofF. psychrophiluminfections, and illustrates that non-lethal time-course blood sampling for individual monitoring of bacteremia is a powerful tool to resolve within-host pathogen behavior in bacterial fish diseases.
Sensitivity to outcome devaluation in operant tasks is better predicted by food restriction level than reinforcement training schedule in mice
Authors: Chevée Maxime , Kim Courtney J. , Crow Nevin , Follman Emma G. , Calipari Erin S. 
Published: February 2023

AbstractBehavioral strategies are often classified based on whether reinforcement is controlled by the value of the reinforcer. Value-sensitive behaviors, in which animals update their actions when reinforcer value is changed, are classified as goal-directed; conversely, value-insensitive actions, where behavior remains consistent when the reinforcer is removed or devalued, are considered habitual. Understanding the features of operant training that bias behavioral control toward either strategy is essential to understanding the cognitive and neuronal processes on which they rely. Using basic reinforcement principles, behavior can be biased toward relying on either process: random ratio (RR) schedules are thought to promote the formation of goal-directed behaviors while random intervals (RI) promote habitual control. However, how the schedule-specific features of these task structures relate to external factors to influence behavior is not well understood. Using male and female mice on distinct food restriction levels, we trained each group on RR schedules with responses-per-reinforcer rates matched to their RI counterparts to control for differences in reinforcement rate. We determined that food restriction level has a stronger effect on the behavior of mice following RR schedules than mice following RI schedules and that food restriction better predicted sensitivity to outcome devaluation than training schedule. Our results support the idea the relationships between RR or RI schedules with goal-directed or habitual behaviors, respectively, are more nuanced than previously appreciated and suggest that an animal’s engagement in a task must be accounted for, together with the structure of reinforcement schedules, to appropriately interpret the cognitive underpinnings of behavior.Significance statementUnderstanding the basic learning principles that control behavior is essential to developing therapies for psychiatric disorders such as addiction or obsessive-compulsive disorder. Reinforcement schedules are thought to control the reliance on habitual versus goal-directed control during adaptive behaviors. However, external factors that are independent of training schedule also influence behavior, for example by modulating motivation or energy balance. In this study, we find that food restriction levels are at least equally important as reinforcement schedules in shaping adaptive behavior. Our results add to the growing body of work showing the distinction between habitual and goal-directed control is nuanced.
Duplex Sequencing Provides Detailed Characterization of Mutation Frequencies and Spectra in the Bone Marrow of MutaMouse Males Exposed to Procarbazine Hydrochloride
Authors: Dodge Annette E. , LeBlanc Danielle P.M. , Zhou Gu , Williams Andrew , Meier Matthew J. , Van Phu , Lo Fang Yin , Valentine Charles C. , Salk Jesse J. , Yauk Carole L. , Marchetti Francesco 
Published: February 2023

ABSTRACTMutagenicity testing is an essential component of health safety assessment. Duplex Sequencing (DS), an emerging high-accuracy DNA sequencing technology, may provide substantial advantages over conventional mutagenicity assays. DS could be used to eliminate reliance on standalone reporter assays and provide mechanistic information alongside mutation frequency (MF) data. However, the performance of DS must be thoroughly assessed before it can be routinely implemented for standard testing. We used DS to study spontaneous and procarbazine (PRC)-induced mutations in the bone marrow (BM) of MutaMouse males across a panel of 20 diverse genomic targets. Mice were exposed to 0, 6.25, 12.5, or 25 mg/kg-bw/day for 28 days by oral gavage and BM sampled 42 days post-exposure. Results were compared with those obtained using the conventionallacZviral plaque assay on the same samples. DS detected significant increases in mutation frequencies and changes to mutation spectra at all PRC doses. Low intra-group variability within DS samples allowed for detection of increases at lower doses than thelacZassay. While thelacZassay initially yielded a higher fold-change in mutant frequency than DS, inclusion of clonal mutations in DS mutation frequencies reduced this discrepancy. Power analyses suggested that three animals per dose group and 500 million duplex base pairs per sample is sufficient to detect a 1.5-fold increase in mutations with >80% power. Overall, we demonstrate several advantages of DS over classical mutagenicity assays and provide data to support efforts to identify optimal study designs for the application of DS as a regulatory test.
FTSH3 facilitates complex I degradation through a direct interaction with the complex I subunit PSST
Authors: Ghifari Abi S. , Ivanova Aneta , Berkowitz Oliver , Whelan James , Murcha Monika W. 
Published: February 2023

AbstractComplex I (NADH dehydrogenase), the largest complex involved in mitochondrial oxidative phosphorylation is composed of nuclear and mitochondrial encoded subunits. Its assembly requires sequential addition of subdomains and modules. As it is prone to oxidative damage, complex I subunits continually undergo proteolysis and turnover. We describe the mechanism by which complex I abundance is regulated in a complex I deficient mutant. Using a forward genetic approach we have identified that the complex I Q-module domain subunit PSST, interacts with FTSH3 (Filamentous Temperature Sensitive H3) to mediate the disassembly of the matrix arm domain module for proteolysis and turnover as a means of protein quality control. We show the direct interaction of FTSH3 with PSST and identify the amino acid residues required for this interaction. It is the ATPase function of FTSH3 that is required for the interaction, as the mutation can be compensated by a proteolytically inactive form of FTSH3. Furthermore, it cannot be compensated by FTSH10 that is also located in mitochondria, as the latter does not interact with PSST. This study reveals the mechanistic process at the resolution of the residues involved of how FTSH3 recognises complex I for degradation.
A Gulf Stream frontal eddy harbors a distinct microbiome compared to adjacent waters
Authors: Gronniger Jessica L. , Gray Patrick C. , Niebergall Alexandria K. , Johnson Zackary I. , Hunt Dana E. 
Published: February 2023

AbstractMesoscale oceanographic features, including eddies, have the potential to alter productivity and other biogeochemical rates in the ocean. Here, we examine the microbiome of a cyclonic, Gulf Stream frontal eddy, with a distinct origin and environmental parameters compared to surrounding waters, in order to better understand the processes dominating microbial community assembly in the dynamic coastal ocean. Our microbiome-based approach identified the eddy as distinct from the surround Gulf Stream waters. The eddy-associated microbial community occupied a larger area than identified by temperature and salinity alone, increasing the predicted extent of eddy-associated biogeochemical processes. While the eddy formed on the continental shelf, after two weeks both environmental parameters and microbiome composition of the eddy were most similar to the Gulf Stream, suggesting the effect of environmental filtering on community assembly or physical mixing with adjacent Gulf Stream waters. In spite of the potential for eddy-driven upwelling to introduce nutrients and stimulate primary production, eddy surface waters exhibit lower chlorophyllaalong with a distinct and less even microbial community, compared to the Gulf Stream. At the population level, the eddy microbiome exhibited differences among the cyanobacteria (e.g. lowerTrichodesmiumand higherProchlorococcus) and in the heterotrophic alpha Proteobacteria (e.g. lower relative abundances of specific SAR11 clades) versus the Gulf Stream. However, better delineation of the relative roles of processes driving eddy community assembly will likely require following the eddy and surrounding waters since inception; additionally, sampling throughout the water column could better clarify the contribution of these mesoscale features to primary production and carbon export in the oceans.
Self-association of a nucleoid-binding protein increases with macromolecular crowding inEscherichia coli
Authors: Pittas Theodoros , Boersma Arnold J. 
Published: February 2023

AbstractMany proteins self-associate to achieve function. Macromolecular crowding enhances protein self-assembly in buffer experiments with added crowders, and crowding could therefore regulate protein function and organization in cells. In eukaryotic cells, protein condensation has been shown to increase with crowding. However, it is unclear what the effect of crowding is on native protein self-assembly in the highly crowdedEscherichia colicell. To determine the role of crowding in the self-assembly of a native protein, we study here the nucleoid-binding H-NS inE. coliand alter macromolecular crowding using a set of perturbations. We followed H-NS self-assembly using a FRET-based method for determining intermolecular interactions with a single genetic intervention. In dilute cell lysate, we see that H-NS self-assembly increases with salts, macromolecular crowding, and its own concentration. InE. coli, the oligomerization increases with crowding. We see that the response of H-NS oligomerization to a sudden crowding change is not immediate but requires time to adapt. Our findings implicate that in-cell crowding affects intracellular organization by promoting self-assembly.
Vagus nerve stimulation using an endovascular electrode array
Authors: Nicolai Evan N. , Arturo Larco Jorge , Madhani Sarosh I. , Asirvatham Samuel J. , Chang Su-youne , Ludwig Kip A. , Savastano Luis E. , Worrell Gregory A. 
Published: February 2023

AbstractVagus nerve stimulation (VNS), which involves a surgical procedure to place electrodes directly on the vagus nerve (VN), is approved clinically for the treatment of epilepsy, depression, and to facilitate rehabilitation in stroke. VNS at surgically implanted electrodes is often limited by activation of motor nerve fibers near and within the VN that cause neck muscle contraction. In this study we investigated endovascular VNS that may allow activation of the VN at locations where the motor nerve fibers are not localized. We used endovascular electrodes within the nearby internal jugular vein (IJV) to electrically stimulate the VN while recording VN compound action potentials and neck muscle motor evoked potentials in an acute intraoperative swine experiment. We show that the stimulation electrode position within the IJV is critical for efficient activation of the VN. We also demonstrate use of fluoroscopy (cone beam CT mode) and ultrasound to determine the position of the endovascular stimulation electrode with respect to the VN and IJV. At the most effective endovascular stimulation locations tested, thresholds for VN activation were several times higher than direct stimulation of the nerve using a cuff electrode; however, this work demonstrates the feasibility of VNS with endovascular electrodes and provides tools to optimize endovascular electrode positions for VNS. The ability to stimulate the VN with endovascular electrodes creates the possibility to stimulate at VN locations that would be otherwise too invasive and at VN locations where structures such as motor nerve fibers do not exist.
The unfolded protein response of the endoplasmic reticulum protectsCaenorhabditis elegansagainst DNA damage caused by stalled replication forks
Authors: Xu Jiaming , Sabatino Brendil , Taubert Stefan 
Published: February 2023

AbstractAll animals must maintain genome and proteome integrity, especially when experiencing endogenous or exogenous stress. To cope, organisms have evolved sophisticated and conserved response systems: unfolded protein responses (UPRs) ensure proteostasis while DNA damage responses (DDRs) maintains genome integrity. Emerging evidence suggests that UPRs and DDRs crosstalk, but this remains poorly understood. Here, we demonstrate that depletion of the DNA primasespri-1orpri-2, which synthesize RNA primers at replication forks and whose inactivation causes DNA damage, activates the UPR of the endoplasmic reticulum (UPR-ER) inCaenorhabditis elegans, with especially strong activation in the germline. We observed activation of both the inositol-requiring-enzyme 1 (ire-1) and the protein kinase RNA-like ER kinase (pek-1) branches of the UPR-ER. Interestingly, activation of the UPR-ER output gene heat shock protein 4 (hsp-4) was partially independent of its canonical activators,ire-1and X-box binding protein (xbp-1), and instead required the third branch of the UPR-ER, activating transcription factor 6 (atf-6), suggesting functional redundancy. We further found that primase depletion specifically induces the UPR-ER, but not the distinct cytosolic or mitochondrial UPRs, suggesting that primase inactivation causes compartment-specific rather than global stress. Functionally, loss ofire-1orpek-1sensitized animals to replication stress caused by hydroxyurea. Finally, transcriptome analysis ofpri-1embryos revealed several deregulated processes that could cause UPR-ER activation, including protein glycosylation, calcium signaling, and fatty acid desaturation. Together, our data show that the UPR-ER, but not other UPRs, responds to replication fork stress and that the UPR-ER is required to alleviate this stress.
Integrating lipid metabolism, pheromone production and perception by Fruitless and Hepatocyte nuclear factor 4
Authors: Sun Jie , Liu Wen-Kan , Ellsworth Calder , Sun Qian , Pan Yu-Feng , Huang Yi-Chun , Deng Wu-Min 
Published: February 2023

AbstractSexual attraction and perception, governed by separate genetic circuits in different organs, are crucial for mating and reproductive success, yet the mechanisms of how these two aspects are integrated remain unclear. InDrosophila, the male-specific isoform of Fruitless (Fru), FruM, is known as a master neuro-regulator of innate courtship behavior to control perception of sex pheromones in sensory neurons. Here we show that the non-sex specific Fru isoform (FruCOM) is necessary for pheromone biosynthesis in hepatocyte-like oenocytes for sexual attraction. Loss of FruCOMin oenocytes resulted in adults with reduced levels of the cuticular hydrocarbons (CHCs), including sex pheromones, and show altered sexual attraction and reduced cuticular hydrophobicity. We further identifyHepatocyte nuclear factor 4(Hnf4) as a key target of FruCOMin directing fatty acid conversion to hydrocarbons in adult oenocytes.fru- andHnf4-depletion disrupts lipid homeostasis, resulting in a novel sex-dimorphic CHC profile, which differs fromdoublesex- andtransformer-dependent sexual dimorphism of the CHC profile. Thus, Fru couples pheromone perception and production in separate organs for precise coordination of chemosensory communication that ensures efficient mating behavior.TeaserFruitless and lipid metabolism regulator HNF4 integrate pheromone biosynthesis and perception to ensure robust courtship behavior.
Intravital imaging of osteocyteαvβ3integrin dynamics with locally injectable fluorescent nanoparticles
Authors: Matthews Melia , Cook Emily , Naguib Nada , Wiesner Uli , Lewis Karl 
Published: February 2023

AbstractOsteocytes are the resident mechanosensory cells in bone. They are responsible for skeletal homeostasis and adaptation to mechanical cues. Integrin proteins play an prominent role in osteocyte mechanotransduction, however the details are not well stratifiedin vivo. Intravital imaging with multiphoton microscopy presents an opportunity to study molecular level mechanobiological eventsin vivo, and could be used to study integrin dynamics in osteocytes. However, fluorescent imaging limitations with respect to excessive optical scattering and low signal to noise ratio caused by mineralized bone matrix make such investigations non-trivial. Here we demonstrate that ultra-small and bright fluorescent core-shell silica nanoparticles (<7nm diameter), known as Cornell Prime Dots (C’Dots), are well-suited for thein vivobone microenvironment and can improve intravital imaging capabilities. We report validation studies for C’Dots as a novel, locally injectedin vivoosteocyte imaging tool for both non-specific cellular uptake and for targeting integrins. The pharmacokinetics of C’Dots reveal distinct sex differences in nanoparticle cycling and clearance in osteocytes, which represents a novel topic of study in bone biology. Integrin-targeted C’Dots were used to study osteocyte integrin dynamics. To the best of our knowledge, we report here the first evidence of osteocyte integrin endocytosis and recyclingin vivo. Our results provide novel insights in osteocyte biology and will open up new lines of investigation that were previously unavailablein vivo.
Striatal enkephalin supports maintenance of conditioned cocaine reward during extinction
Authors: Matsumura Kanako , Choi In Bae , Asokan Meera , Le Nathan N. , Natividad Luis , Dobbs Lauren K. 
Published: February 2023

AbstractDrug predictive cues and contexts exert powerful control over behavior and can incite drug seeking and taking. This association and the behavioral output are encoded within striatal circuits, and regulation of these circuits by G-protein coupled receptors affects cocaine-related behaviors. Here, we investigated how opioid peptides and G-protein coupled opioid receptors expressed in striatal medium spiny neurons (MSNs) regulate conditioned cocaine seeking. Augmenting levels of the opioid peptide enkephalin in the striatum facilitates acquisition of cocaine conditioned place preference (CPP). In contrast, opioid receptor antagonists attenuate cocaine CPP and facilitate extinction of alcohol CPP. However, whether striatal enkephalin is necessary for acquisition of cocaine CPP and maintenance during extinction remains unknown. We generated mice with a targeted deletion of enkephalin from dopamine D2-receptor expressing MSNs (D2-PenkKO) and tested them for cocaine CPP. Low striatal enkephalin levels did not attenuate acquisition or expression of CPP; however, D2-PenkKOs showed faster extinction of cocaine CPP. Single administration of the non-selective opioid receptor antagonist naloxone prior to preference testing blocked expression of CPP selectively in females, but equally between genotypes. Repeated administration of naloxone during extinction did not facilitate extinction of cocaine CPP for either genotype, but rather prevented extinction in D2-PenkKO mice. We conclude that while striatal enkephalin is not necessary for acquisition of cocaine reward, it maintains the learned association between cocaine and its predictive cues during extinction learning. Further, sex and pre-existing low striatal enkephalin levels may be important considerations for use of naloxone in treating cocaine use disorder.
Oral CBD treatment is associated with an anti-inflammatory gene expression signature in myeloid cells of people living with HIV
Authors: Marini Simone , Huber Amanda , Cash Melanie N. , Salemi Marco , Cook Robert L , Borsa Paul , Mavian Carla N. 
Published: February 2023

AbstractHIV-related comorbidities appear to be related to chronic inflammation, a condition characterizing people living with HIV (PLWH). Prior work indicates that cannabidiol (CBD) might reduce inflammation; however, the genetics underpinning of this effect are not well investigated. Our main objective is to detect gene expression alterations in human peripheral blood mononuclear cells (PBMCs) from PLWH after at least one month of CBD treatment.We analyze ∼41,000 PBMCs from three PLWH at baseline and after CBD treatment (27-60 days). We obtained a coherent signature, characterized by an anti-inflammatory activity, of differentially expressed genes in myeloid cells.Our study shows how CBD is associated with alterations of gene expression in myeloid cells after CBD treatment.