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We investigated whether the 2 Hz electroacupuncture (EA) analgesia is associated with phosphorylation of N-methyl-D-aspartate receptor (NMDAR) NR-1 subunits and NMDAR antagonism in the lumbar spinal cord of rats. EA stimulation produced an increase of serine phosphorylation of NMDAR NR-1 subunits in the spinal cord as compared with normal conditions. However, the intrathecal injection of NMDAR antagonist D-2-amino-5-phosphonopentanoic acid significantly prevented serine phosphorylation of NMDAR NR-1 subunits induced by EA stimulation in the dorsal horn of spinal cord. These results indicate that EA analgesia by stimulation of peripheral nerves may be involved in an increase of NR-1 serine phosphorylation in the dorsal horn of the spinal cord.

Colorectal cancer is the third leading cause of cancer-related death worldwide. Hence, there is a need to identify new therapeutic agents to improve the current repertoire of therapeutic drugs. Wogonin, a flavonoid from the herbal medicine Scutellaria baicalensis, has unique antitumor activity. Our study aimed to further explore the inhibitory effects of wogonin on colorectal cancer and its specific mechanism. The results showed that wogonin significantly inhibited the proliferation of colorectal cancer cells as well as their ability to invade and metastasize. We detected phosphorylation of tumor-associated signaling pathways using a phosphorylated protein microarray and found that wogonin intervention significantly inhibited the phosphorylation level of the AKT protein in colorectal cancer cells. Through in vitro and in vivo experiments, it was confirmed that wogonin exerted its antitumor effects against colorectal cancer by inhibiting phosphorylation in the AKT pathway. Our discovery of wogonin as an inhibitor of AKT phosphorylation provides new opportunities for the pharmacological treatment of colorectal cancer.

Artemisinin (ART) and its derivatives, collectively referred to as artemisinins (ARTs), have been approved for the treatment of malaria for decades. ARTs are converted into dihydroartemisinin (DHA), the only active form, which is reductive in vivo. In this review, we provide a brief overview of the neuroprotective potential of ARTs and the underlying mechanisms on several of the most common neurodegenerative diseases, particularly considering their potential application in those associated with cognitive and motor impairments including Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), and amyotrophic lateral sclerosis (ALS). ARTs act as autophagy balancers to alleviate AD and PD. They inhibit neuroinflammatory responses by regulating phosphorylation of signal transduction proteins, such as AKT, PI3K, ERK, NF-κB, p38 MAPK, IκBα. In addition, ARTs regulate GABAergic signaling in a dose-dependent manner. Although they competitively inhibit the binding of gephyrin to GABAergic receptors, low doses of ARTs enhance GABAergic signaling. ARTs can also inhibit ferroptosis, activate the Akt/Bcl-2, AMPK, or ERK/CREB pathways to reduce oxidative stress, and maintain mitochondrial homeostasis, protecting neurons from oxidative stress injury. More importantly, ARTs structurally combine with and suppress β-Amyloid (A$\beta )$-induced neurotoxicity, reduce P-tau, and maintain O-GlcNAcylation/Phosphorylation balance, leading to relieved pathological changes in neurodegenerative diseases. Collectively, these natural properties endow ARTs with unique potential for application in neurodegenerative diseases.

Many studies suggest that regular physical activity can reduce the opportunity of Alzheimer’s disease (AD) and slow its onset and progression. However, the exact mechanism is still unclear. Clinically, amyloid plaques and neurofibrillary tangles are the two characterizations of AD, which are associated with amyloid-$\beta$ and tau hyperphosphorylation, respectively. The PI3K/Akt signaling pathway regulates tau phosphorylation and has a pivotal role in the development of pathology in AD. Therefore, we try to investigate the effects of aerobic exercise on tau phosphorylation and examine whether these effects were mediated by the PI3K/Akt pathway in the hippocampus of APP/PS1 and C57BL/6J mice. 40 male APP/PS1 mice and 40 male C57BL/6J mice were randomly divided into four groups respectively: sedentary group, exercise group, sedentary with GNE-317 treatment group and exercise with GNE-317 treatment group. The mice in the exercise group and exercise with GNE-317 treatment group were given exercise training on a treadmill for 8 weeks. After 8 weeks of treadmill exercise, the morris water maze, immunohistochemistry and western blot analysis were performed. We found out that 8 weeks of aerobic exercise enhanced PI3K expression and increased p-Akt${}^{\mathrm{\text{Thr}}308}$, p-Akt${}^{\mathrm{\text{Ser}}473}$ and p-GSK3${\beta }^{\mathrm{\text{Ser}}9}$. Furthermore, 8 weeks of aerobic exercise reduced tau phosphorylation at multiple sites including Ser202, Thr231 and Ser396. In the morris water maze, the exercise group showed a reduced escape time and distance compared with those of the sedentary group, suggesting that aerobic exercise improved the cognitive ability in mouse. While the above-mentioned results were attenuated in the PI3K/Akt inhibitor GNE-317 treatment groups. Our study demonstrated that 8 weeks of aerobic exercise could reduce tau phosphorylation and improve cognitive functions by activating the PI3K/Akt pathway in the hippocampus of APP/PS1 and C57BL/6J mice.

A major goal of molecular biology is to correlate molecular structure with function. Since most enzymes and biological catalysts are proteins, the focus for correlating 'form' with 'function' has been entirely on protein macromolecular structure. It is obvious that any understanding of protein function must come through an understanding protein dynamics. Furthermore, all of the regulatory reactions are through changes in dynamics brought about by post-translational modifications, the most important of which is phosphorylation. This review highlights the important role of covalent phosphorylation and noncovalent phosphates in regulating allosteric effects and function through a study of protein dynamics. Mass spectrometry is a relatively new and increasingly important tool for describing protein dynamics. All examples described in this review have been studied by amide hydrogen/deuterium exchange mass spectrometry.

Protein phosphorylation is a very common post-translational modification, catalyzed by kinases, for signaling and regulation. Phosphotyrosines frequently target SH2 domains. The spleen tyrosine kinase (Syk) is critical for tyrosine phosphorylation of multiple proteins and for regulation of important pathways. Phosphorylation of both Y342 and Y346 in Syk linker B is required for optimal signaling. The SH2 domains of Vav1 and PLC-γ both bind this doubly phosphorylated motif. Here we used a recently developed method to calculate the effects of Y342 and Y346 phosphorylation on the rate constants of a peptide from Syk linker B binding to the SH2 domains of Vav1 and PLC-γ. The predicted effects agree well with experimental observations. Moreover, we found that the same doubly phosphorylated peptide binds the two SH2 domains via distinct mechanism, with apparent rigid docking for Vav1 SH2 and dock-and-coalesce for PLC-γ SH2.

Learning, memory and long-term potentiation (LTP) are supported by factors including post-synaptic calcium ion flux activating and transforming the hexagonal calcium-calmodulin kinase II (CaMKII) holoenzyme. Upon calcium-induced activation, up to six kinase domains extend upward, and up to six kinase domains extend downward from the CaMKII association domain, the fully activated holoenzyme resembling a robotic insect 20 nanometers in length. Each extended kinase domain can be phosphorylated, and able to phosphorylate other proteins, thus potentially further encoding synaptic information at intraneuronal molecular sites for memory storage, processing and distribution. Candidate sites for phosphorylation-encoded molecular memory include microtubules, cylindrical lattice polymers of the protein tubulin. Using molecular modeling, we find spatial dimensions and geometry of the six extended CaMKII kinase domains can precisely match those of microtubule hexagonal lattice neighborhoods (both A- and B-lattices), and show two feasible phosphorylation mechanisms. In one, phosphorylation sites (e.g., valine 208) on a CaMKII extended kinase domain interact with serine 444 on a C-terminal "tail" of tubulin. In the second, the CaMKII kinase domain unfurls, enabling phosphorylation sites to contact threonine and serine sites on the tubulin surface. We suggest sets of six CaMKII kinase domains phosphorylate hexagonal microtubule lattice neighborhoods collectively, e.g., conveying synaptic information as ordered arrays of six "bits", and thus a "byte", with (minimally) 2⁶ (64) possible bit states per CaMKII-microtubule interaction. We model two levels of interaction between CaMKII and microtubules, suggesting a testable framework for molecular memory encoding.

Protein phosphorylation catalyzed by kinases plays essential roles in various intracellular processes. With an increasing number of phosphorylation sites verified experimentally by high-throughput technologies and assigned as substrates of specific kinases, prediction of potential kinase–substrate relations (KSRs) attracts increasing attention. Although a large number of computational methods have been designed, most of them only focus on local protein sequence information. A few KSR prediction approaches integrate protein–protein interaction and protein sequence information into existing machine learning algorithms at the cost of high feature dimensions or reduced sensitivity. In this work, we introduce two novel heterogeneous networks, HetNet-PPI and HetNet-SEQ, by incorporating PPI and similarity of protein sequences into the kinase–substrate heterogeneous networks, respectively. Based on these two heterogeneous networks, we further propose two new KSR prediction methods, HeteSim-PPI and HeteSim-SEQ, by adopting the HeteSim algorithm, which is recently proposed for relevance measure in heterogeneous information networks. Comprehensive evaluation results of the two methods show that similarity of protein sequences is more effective in improving KSR prediction performance as HeteSim-SEQ outperforms HeteSim-PPI in most cases. Further comparison results demonstrate that HeteSim-SEQ is superior to existing methods including BDT, SVM and iGPS, suggesting the effectiveness of the proposed network-based method in predicting potential KSRs.

Aromatic copolyamides were synthesized by the Yamazaki phosphorylation method starting from bis(4-carboxyphenyl) phenyl phosphine oxide, terephthalic acid and 4,4′-diaminodiphenyl methane. The copolymers with inherent viscosities of 0.52–0.99 dL/g were obtained. The structures of the copolyamides were characterized by elemental analysis, FTIR and NMR. The glass transition temperatures were measured by DSC and DMA, respectively, and the results showed that the T_gs of the polymers were higher than 287°C. Thermal decomposition temperatures of the copolyamides at 5% weight loss were found in the range of 423–469°C by TGA. Most of the copolymers were readily soluble in a variety of organic solvents such as NMP, DMAc, m-cresol and so on. The tensile experiments of the thin films showed that the polymers had good mechanical properties.

A calcium phosphate coating over porous chitosan sponges was produced by a process based on phosphorylation, Ca(OH)₂ treatment and SBF immersion. Porous chitosan sponges were prepared first by dissolving chitosan powder in acetic acid, and then freeze-drying. The obtained porous sponges were washed with ethanol containing sodium hydroxide. Sponges not subjected to the sodium hydroxide treatment were easy to dissolve in water. Sponges were phosphorylated by using urea and phosphoric acid in DMF solution. Phosphorylated chitosan sponges was soaked in saturated Ca(OH)₂ solution at ambient temperature, which lead to the rapid formation of calcium phosphate coatings and were found to stimulate the growth of a calcium phosphate coating on their surfaces after soaking in SBF solution. The mechanism of formation of the calcium phosphate coatings on the chitosan sponges must involve a diffusion of the phosphorus ion from the interior of the sponges, so creating a sufficiently high local concentration of ions at the surface to facilitate precipitation of calcium phosphate from the soaking medium.