BackgroundThe crotonylation of histones is discovered of late as one of the post-translational modifications (PTMs) that can regulate gene expression. However, the function of crotonylation on nonhistone proteins in vascular smooth muscle cells (VSMCs) is unclear. Here, we aim to find the cellular characteristics of crotonylated nonhistone proteins and the cross talk with ubiquitinated proteins in VSMC phenotypic remodeling using the modified omics and proteomic analysis.MethodsWe performed the modified omics and proteomic analysis of VSMCs before and after the stimulation with platelet-derived growth factor-BB (PDGF-BB). The crotonylated and ubiquitinated pan-antibody was used to enrich proteins and then subjected to a high-throughput mass spectrometry analysis. The enrichment analysis was performed within differentially modified proteins in regard to GO terms, KEGG, and protein domains.ResultsAs a result, there were 2,138 crotonylation sites in 534 proteins and 1,359 ubiquitination sites corresponding to 657 proteins. These crotonylated proteins detected after PDGF-BB stimulation might be involved in various vital cellular pathways and carry out important functions in VSMCs. Some of them closely took part in significant physiological processes of VSMC phenotypic remodeling, including glycolysis/gluconeogenesis, vascular smooth muscle contraction, and the PI3K-Akt signaling pathway. Furthermore, the KEGG pathway enrichment analysis showed the involvement of ubiquitinated proteins in the physiological processes of VSMC phenotypic remodeling, including glycolysis/gluconeogenesis, vascular smooth muscle contraction, RAS signaling pathway, or the PI3K-Akt signaling pathway. A cross talk analysis showed that there were 199 sites within the 177 proteins modified by crotonylation and ubiquitination simultaneously. Protein–protein interaction (PPI) network analysis indicated that crotonylated and ubiquitinated proteins play an important role in cellular bioprocess commonly and possibly have a synergistic effect.ConclusionIn summary, our bioinformatics analysis shows that the crotonylation and ubiquitination of nonhistone proteins play an essential role in VSMC phenotypic transformation induced by PDGF-BB stimulation. The cross talk between crotonylation and ubiquitination in glycolysis is possibly a novel mechanism during VSMC phenotypic remodeling.
Resistance spot welding (RSW) exhibits low heat input and high efficiency. However, because Mo exhibits low resistivity and high hot strength, it is difficult to effectively combine the resistance spot welded joints of Mo. The lap joint of 1-mm-thick Mo sheets was welded using RSW. Moreover, the welding parameters (current, welding duration, and electrode force) were optimised. Using Ti foil as the interlayer, the influence of the alloying element on the resistance spot welded joint of the Mo sheets was explored. The results indicate that the success rate of welding can be improved by utilising a high current and short welding duration, and increasing the electrode force causes reduced contact resistance and further failure of the welding. In addition, an excessively high electrode force may result in electrode adhesion. Here, a current of 20 kA, welding duration of 0.4 s, and electrode force of 3726 N were used as the optimised parameters. The joint obtained under the parameters can withstand the highest shear load (about 2.20 kN); the shear load of the joint obtained after adding the Ti interlayer (thickness: 0.03 mm) increases by approximately 54%. After adding the Ti foil, the heat input on the interface increased and Ti melted to form metallurgical bonding with Mo. Under these conditions, the interfacial strength increased significantly. During the tensile–shear test, the heat-affected zone of Mo is fractured, in which the shear fracture is subjected to brittle failure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.