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With the development of manufacturing industry, more and more torque tools are used in various industrial fields, such as torque wrench, torque multiplier, hydraulic torque wrench, electric torque wrench, various torque sensors, etc. The calibration of these tools is related to the quality of manufacturing products. National institute of metrology of China has established several torque standard devices and carried out calibration of various torque tools. This paper introduces the related work.

Summary: Molecular mechanisms underlying quantitative variations of pathogenicity remain elusive. Here, we identified the Xanthomonas campestris XopJ6 effector that triggers disease resistance in cauliflower and Arabidopsis thaliana. XopJ6 is a close homolog of the Ralstonia pseudosolanacearum PopP2 YopJ family acetyltransferase. XopJ6 is recognized by the RRS1-R/RPS4 NLR pair that integrates a WRKY decoy domain mimicking effector targets. We identified a XopJ6 natural variant carrying a single residue substitution in XopJ6 WRKY-binding site that disrupts interaction with WRKY proteins. This mutation allows XopJ6 to evade immune perception while retaining some XopJ6 virulence functions. Interestingly, xopJ6 resides in a Tn3-family transposon likely contributing to xopJ6 copy number variation (CNV). Using synthetic biology, we demonstrate that xopJ6 CNV tunes pathogen virulence on Arabidopsis through gene dosage-mediated modulation of xopJ6 expression. Together, our findings highlight how sequence and structural genetic variations restricted at a particular effector gene contribute to bacterial host adaptation.

The effects of different preheating treatments on the microstructure and mechanical properties of extruded Mg–13Gd–4Y–2Zn–0.5Zr (wt.%) alloys were investigated by using high-throughput experiments in this paper. The results showed that the solid solution and aging prior to extrusion (SAE) samples with heterogeneous microstructure had the best strength-plasticity synergy with ultimate tensile strength (UTS), yield strength (TYS) and elongation (EL) reaching 446.35 ± 3.1 MPa, 382.5 ± 2.5 MPa and 6.5 ± 0.8%, respectively. The formation of heterogeneous microstructures was mainly attributed to the weakening of the particle stimulation nucleation (PSN) effect by the dissolution of the primary Mg5RE phase during the solid solution process and the strong Zener pinning effect of the dynamic Mg5RE phase precipitation during the extrusion process, which inhibited grain boundary migration and grain growth. Optimum strength-plasticity synergy was due to fine grain strengthening, second phase strengthening, texture strengthening and heterogeneous deformation induced (HDI) strengthening. Strain gradients between deformed grains and dynamic recrystallized (DRXed) grains were generated during deformation process, in order to coordinate the deformation and generate more geometrically necessary dislocations (GNDs) within the deformed grains, resulting in a strong HDI effect. The increase in plasticity was mainly attributed to the change in texture type due to the rotation of the lattice, which promoted the activation of non-basal slip systems. This study provided an efficient and rapid method for probing optimal heat treatment parameters, aiming to reduce the influence of uncontrollable factors on experimental results and increase the rigor of the experiment.

We report that the mammalian 5-methylcytosine (5mC) oxidase Tet3 exists as three major isoforms and characterized the full-length isoform containing an N-terminal CXXC domain (Tet3FL). This CXXC domain binds to unmethylated CpGs, but, unexpectedly, its highest affinity is toward 5-carboxylcytosine (5caC). We determined the crystal structure of the CXXC domain-5caC-DNA complex, revealing the structural basis of the binding specificity of this domain as a reader of CcaCG sequences. Mapping of Tet3FL in neuronal cells shows that Tet3FL is localized precisely at the transcription start sites (TSSs) of genes involved in lysosome function, mRNA processing, and key genes of the base excision repair pathway. Therefore, Tet3FL may function as a regulator of 5caC removal by base excision repair. Active removal of accumulating 5mC from the TSSs of genes coding for lysosomal proteins by Tet3FL in postmitotic neurons of the brain may be important for preventing neurodegenerative diseases.

The protein stability and chromatin functions of UHRF1 (ubiquitin-like, containing PHD and RING finger domains, 1) are regulated in a cell-cycle-dependent manner. We report a structural characterization of the complex between UHRF1 and the deubiquitinase USP7. The first two UBL domains of USP7 bind to the polybasic region (PBR) of UHRF1, and this interaction is required for the USP7-mediated deubiquitination of UHRF1. Importantly, we find that the USP7-binding site of the UHRF1 PBR overlaps with the region engaging in an intramolecular interaction with the N-terminal tandem Tudor domain (TTD). We show that the USP7-UHRF1 interaction perturbs the TTD-PBR interaction of UHRF1, thereby shifting the conformation of UHRF1 from a TTD-“occluded” state to a state open for multivalent histone binding. Consistently, introduction of a USP7-interaction-defective mutation to UHRF1 significantly reduces its chromatin association. Together, these results link USP7 interaction to the dynamic deubiquitination and chromatin association of UHRF1.

The DEAD-box adenosine triphosphatase (ATPase) Prp5p facilitates U2 small nuclear ribonucleoprotein particle (snRNP) binding to the intron branch site region during spliceosome assembly. We present crystal structures of S. cerevisiae Prp5p alone and in complex with ADP at 2.12 Å and 1.95 Å resolution. The three-dimensional packing of Prp5p subdomains differs strikingly from that so far observed in other DEAD-box proteins: two RecA-like subdomains adopt an “open state” conformation stabilized by extensive interactions involving sequences that flank the two subdomains. This conformation is distinct from that required for ATP hydrolysis. Consistent with this, Prp5p mutations that destabilize interdomain interactions exhibited increased ATPase activity in vitro and inhibited splicing of suboptimal branch site substrates in vivo, whereas restoration of interdomain interactions reversed these effects. We conclude that the Prp5p open state conformation is biologically relevant and that disruption of the interdomain interaction facilitates a large-scale conformational change of Prp5p during U2 snRNP-branch site recognition.