In order to investigate the molecular mechanism of silk/threonine protein kinase (STK)-mediated blue light response in the algal Chlamydomonas reinhardtii, phenotype identification and transcriptome analysis were conducted for C. reinhardtii STK mutant strain crstk11 (with an AphvIII box reverse insertion in stk11 gene coding region) under blue light stress. Phenotypic examination showed that under normal light (white light), there was a slight difference in growth and pigment contents between the wild-type strain CC5325 and the mutant strain crstk11. Blue light inhibited the growth and chlorophyll synthesis in crstk11 cells, but significantly promoted the accumulation of carotenoids in crstk11. Transcriptome analysis showed that 860 differential expression genes (DEG) (559 up-regulated and 301 down-regulated) were detected in mutant (STK4) vs. wild type (WT4) upon treatment under high intensity blue light for 4 days. After being treated under high intensity blue light for 8 days, a total of 1 088 DEGs (468 upregulated and 620 downregulated) were obtained in STK8 vs. WT8. KEGG enrichment analysis revealed that compared to CC5325, the crstk11 blue light responsive genes were mainly involved in catalytic activity of intracellular photosynthesis, carbon metabolism, and pigment synthesis. Among them, upregulated genes included psaA, psaB, and psaC, psbA, psbB, psbC, psbD, psbH, and L, petA, petB, and petD, as well as genes encoding ATP synthase α, β and c subunits. Downregulated genes included petF and petJ. The present study uncovered that the protein kinase CrSTK11 of C. reinhardtii may participate in the blue light response of algal cells by mediating photosynthesis as well as pigment and carbon metabolism, providing new knowledge for in-depth analysis of the mechanism of light stress resistance in the algae.
Chlamydomonas reinhardtii/genetics* ; Photosynthesis/genetics* ; Plants/metabolism* ; Protein Kinases ; Threonine/metabolism* ; Carbon/metabolism* ; Serine/metabolism*

This study investigated the mechanism of Danggui Shaoyao Powder(DSP) against mitophagy in rat model of Alzheimer's disease(AD) induced by streptozotocin(STZ) based on PTEN induced putative kinase 1(PINK1)-Parkin signaling pathway. The AD rat model was established by injecting STZ into the lateral ventricle, and the rats were divided into normal group, model group, DSP low-dose group(12 g·kg~(-1)·d~(-1)), DSP medium-dose group(24 g·kg~(-1)·d~(-1)), and DSP high-dose group(36 g·kg~(-1)·d~(-1)). Morris water maze test was used to detect the learning and memory function of the rats, and transmission electron microscopy and immunofluorescence were employed to detect mitophagy. The protein expression levels of PINK1, Parkin, LC3BⅠ/LC3BⅡ, and p62 were assayed by Western blot. Compared with the normal group, the model group showed a significant decrease in the learning and memory function(P<0.01), reduced protein expression of PINK1 and Parkin(P<0.05), increased protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05), and decreased occurrence of mitophagy(P<0.01). Compared with the model group, the DSP medium-and high-dose groups notably improved the learning and memory ability of AD rats, which mainly manifested as shortened escape latency, leng-thened time in target quadrants and elevated number of crossing the platform(P<0.05 or P<0.01), remarkably activated mitophagy(P<0.05), up-regulated the protein expression of PINK1 and Parkin, and down-regulated the protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05 or P<0.01). These results demonstrated that DSP might promote mitophagy mediated by PINK1-Parkin pathway to remove damaged mitochondria and improve mitochondrial function, thereby exerting a neuroprotective effect.
Rats ; Animals ; Mitophagy ; Alzheimer Disease/genetics* ; Powders ; Protein Kinases/metabolism* ; Ubiquitin-Protein Ligases/metabolism*

OBJECTIVEMicroRNAs (miRNAs or miRs) play critical roles in the fibrotic process in different organs. We summarized the latest research progress on the roles and mechanisms of miRNAs in the regulation of the molecular signaling pathways involved in fibrosis.

DATA SOURCESPapers published in English from January 2010 to August 2015 were selected from the PubMed and Web of Science databases using the search terms "microRNA", "miR", "transforming growth factor β", "tgf β", "mitogen-activated protein kinase", "mapk", "integrin", "p38", "c-Jun NH2-terminal kinase", "jnk", "extracellular signal-regulated kinase", "erk", and "fibrosis".

STUDY SELECTIONArticles were obtained and reviewed to analyze the regulatory effects of miRNAs on molecular signaling pathways involved in the fibrosis.

RESULTSRecent evidence has shown that miRNAs are involved in regulating fibrosis by targeting different substrates in the molecular processes that drive fibrosis, such as immune cell sensitization, effector cell activation, and extracellular matrix remodeling. Moreover, several important molecular signaling pathways involve in fibrosis, such as the transforming growth factor-beta (TGF-β) pathway, mitogen-activated protein kinase (MAPK) pathways, and the integrin pathway are regulated by miRNAs. Third, regulation of the fibrotic pathways induced by miRNAs is found in many other tissues in addition to the heart, lung, liver, and kidney. Interestingly, the actions of many drugs on the human body are also induced by miRNAs. It is encouraging that the fibrotic process can be blocked or reversed by targeting specific miRNAs and their signaling pathways, thereby protecting the structures and functions of different organs.

CONCLUSIONSmiRNAs not only regulate molecular signaling pathways in fibrosis but also serve as potential targets of novel therapeutic interventions for fibrosing diseases.

Animals ; Extracellular Signal-Regulated MAP Kinases ; genetics ; metabolism ; Fibrosis ; genetics ; metabolism ; Humans ; MicroRNAs ; genetics ; Mitogen-Activated Protein Kinases ; genetics ; metabolism ; Transforming Growth Factor beta ; genetics ; metabolism

The 26S proteasome at the center of the ubiquitin-proteasome system (UPS) is essential for virtually all cellular processes of eukaryotes. A common misconception about the proteasome is that, once made, it remains as a static and uniform complex with spontaneous and constitutive activity for protein degradation. Recent discoveries have provided compelling evidence to support the exact opposite insomuch as the 26S proteasome undergoes dynamic and reversible phosphorylation under a variety of physiopathological conditions. In this review, we summarize the history and current understanding of proteasome phosphorylation, and advocate the idea of targeting proteasome kinases/phosphatases as a new strategy for clinical interventions of several human diseases.
Animals ; Humans ; Phosphoprotein Phosphatases ; genetics ; metabolism ; Phosphorylation ; genetics ; Proteasome Endopeptidase Complex ; genetics ; metabolism ; Protein Kinases ; genetics ; metabolism

Fusobacterium nucleatum is an opportunistic pathogenic bacterium that can be enriched in colorectal cancer tissues, affecting multiple stages of colorectal cancer development. The two-component system plays an important role in the regulation and expression of genes related to pathogenic resistance and pathogenicity. In this paper, we focused on the CarRS two-component system of F. nucleatum, and the histidine kinase protein CarS was recombinantly expressed and characterized. Several online software such as SMART, CCTOP and AlphaFold2 were used to predict the secondary and tertiary structure of the CarS protein. The results showed that CarS is a membrane protein with two transmembrane helices and contains 9 α-helices and 12 β-folds. CarS protein is composed of two domains, one is the N-terminal transmembrane domain (amino acids 1-170), the other is the C-terminal intracellular domain. The latter is composed of a signal receiving domain (histidine kinases, adenylyl cyclases, methyl-accepting proteins, prokaryotic signaling proteins, HAMP), a phosphate receptor domain (histidine kinase domain, HisKA), and a histidine kinase catalytic domain (histidine kinase-like ATPase catalytic domain, HATPase_c). Since the full-length CarS protein could not be expressed in host cells, a fusion expression vector pET-28a(+)-MBP-TEV-CarS_cyto was constructed based on the characteristics of secondary and tertiary structures, and overexpressed in Escherichia coli BL21-Codonplus(DE3)RIL. CarS_cyto-MBP protein was purified by affinity chromatography, ion-exchange chromatography, and gel filtration chromatography with a final concentration of 20 mg/ml. CarS_cyto-MBP protein showed both protein kinase and phosphotransferase activities, and the MBP tag had no effect on the function of CarS_cyto protein. The above results provide a basis for in-depth analysis of the biological function of the CarRS two-component system in F. nucleatum.
Humans ; Histidine Kinase/metabolism* ; Fusobacterium nucleatum/metabolism* ; Automobiles ; Protein Kinases/genetics* ; Escherichia coli/metabolism* ; Colorectal Neoplasms

OBJECTIVES: This study aimed to explore the specific mechanism, mediated by the reactive oxygen species (ROS) and PINK1/Parkin pathway, of the mitochondrial autophagy of human periodontal ligament cells (hPDLCs) under starvation conditions. METHODS: hPDLCs were isolated and cultured from normal periodontal tissues. Earle's balanced salt solution (EBSS) was used to simulated a starvation environment and thus stimulate hPDLCs mitochondrial autophagy. N-Acetyl-L-cysteine (NAC) was used to inhibit ROS production to explore the role of ROS in hPDLC mitochondrial autophagy. Cyclosporin A was used to inhibit the PINK1/Parkin pathway to study the role of ROS and the PINK1/Parkin pathway in hPDLCs activation under starvation. The mitochondrial membrane potential was detected by flow cytometry with a JC-1 mitochondrial membrane potential detection kit. The morphological structure of mitochondria and the formation of mitochondrial autophagosome were observed by transmission electron microscopy. Mito tracker red cmxros and lyso tracker green staining were used to observe the localization of mitochondria and lysosomes. The formation intensity of ROS was detected with a DCFH-DA ROS fluorescent probe. The expression levels of mitochondrial autophagy genes (Tomm20 and Timm23) and the PINK1/Parkin pathway were detected by real-time quantitative polymerase chain reaction (RT-qPCR). The expression levels of mitochondrial autophagy proteins (Tomm20 and Timm23) and PINK1/Parkin protein were detected by Western blot. RESULTS: EBSS starvation for 30 min induced the strongest activation of hPDLCs mitochondrial autophagy, increased the expression of ROS, downregulated the expression of mitochondrial autophagy-related genes (Tomm20 and Timm23) (P<0.001), and upregulated the PINK1/Parkin pathway (P<0.001). After NACinhibited ROS production, mitochondrial autophagy was also inhibited. Meanwhile, the expression of Tomm20 and Timm23 was upregulated (P<0.001 and P<0.05), and the expression of the PINK1/parkin pathway (P<0.001 and P<0.05) was down regulated. When cyclosporin A inhibited the expression of the PINK1/Parkin pathway (P<0.05 and P<0.05), it reversed the mitochondrial autophagy of hPDLCs (P<0.001 and P<0.01) and also upregulated the expression of Tomm20 and Timm23 (P<0.001 and P<0.01). CONCLUSIONS ROS enhanced the mitochondrial autophagy of hPDLCs primarily through the PINK1/Parkin pathway under starvation conditions.
Humans ; Mitophagy/genetics* ; Reactive Oxygen Species/metabolism* ; Periodontal Ligament/metabolism* ; Cyclosporine ; Protein Kinases/metabolism* ; Ubiquitin-Protein Ligases/metabolism*

Arabidopsis ; chemistry ; genetics ; metabolism ; Arabidopsis Proteins ; chemistry ; genetics ; metabolism ; Crystallography, X-Ray ; Intercellular Signaling Peptides and Proteins ; chemistry ; genetics ; metabolism ; Protein Conformation ; Protein-Serine-Threonine Kinases ; chemistry ; genetics ; metabolism

Timely cell cycle regulation is conducted by sequential activation of a family of serine-threonine kinases called cycle dependent kinases (CDKs). Tight CDK regulation involves cyclin dependent kinase inhibitors (CKIs) which ensure the correct timing of CDK activation in different phases of the cell cycle. One CKI of importance is p27(KIP1). The regulation and cellular localization of p27(KIP1) can result in biologically contradicting roles when found in the nucleus or cytoplasm of both normal and tumor cells. The p27(KIP1) protein is mainly regulated by proteasomal degradation and its downregulation is often correlated with poor prognosis in several types of human cancers. The protein can also be functionally inactivated by cytoplasmic localization or by phosphorylation. The p27(KIP1) protein is an unconventional tumor suppressor because mutation of its gene is extremely rare in tumors, implying the normal function of the protein is deranged during tumor development. While the tumor suppressor function is mediated by p27(KIP1)'s inhibitory interactions with the cyclin/CDK complexes, its oncogenic function is cyclin/CDK independent, and in many cases correlates with cytoplasmic localization. Here we review the basic features and novel aspects of the p27(KIP1) protein, which displays genetically separable tumor suppressing and oncogenic functions.
Animals ; Cyclin-Dependent Kinases/genetics/*metabolism ; Humans ; Intracellular Signaling Peptides and Proteins/genetics/*metabolism ; Mutation ; Neoplasms/genetics/*metabolism ; Phosphorylation/genetics ; Protein Transport/genetics ; Tumor Suppressor Proteins/genetics/*metabolism

Mitophagy is one of the important targets for the prevention and treatment of myocardial ischemia/reperfusion injury (MIRI). Moderate mitophagy can remove damaged mitochondria, inhibit excessive reactive oxygen species accumulation, and protect mitochondria from damage. However, excessive enhancement of mitophagy greatly reduces adenosine triphosphate production and energy supply for cell survival, and aggravates cell death. How dysfunctional mitochondria are selectively recognized and engulfed is related to the interaction of adaptors on the mitochondrial membrane, which mainly include phosphatase and tensin homolog deleted on chromosome ten (PTEN)-induced kinase 1/Parkin, hypoxia-inducible factor-1 α/Bcl-2 and adenovirus e1b19k Da interacting protein 3, FUN-14 domain containing protein 1 receptor-mediated mitophagy pathway and so on. In this review, the authors briefly summarize the main pathways currently studied on mitophagy and the relationship between mitophagy and MIRI, and incorporate and analyze research data on prevention and treatment of MIRI with Chinese medicine, thereby provide relevant theoretical basis and treatment ideas for clinical prevention of MIRI.
Humans ; Mitochondria/metabolism* ; Mitophagy/genetics* ; Myocardial Reperfusion Injury ; Protein Kinases/metabolism*

BACKGROUNDPreviously, we reported that dual-specificity phosphatase 1 (DUSP1) was differentially expressed in endometrioid adenocarcinoma (EEA). However, the role of DUSP1 in EEA progression and the relationship between DUSP1 and medroxyprogesterone (MPA) are still unclear.

METHODSThe expression of DUSP1 in EEA specimens was detected by immunohistochemical analysis. The effect of DUSP1 on cell proliferation was analyzed by Cell Counting Kit 8 and colony formation assay, and cell migration was analyzed by transwell assay. MPA-induced DUSP1 expression in EEA cells was measured by Western blot.

RESULTSDUSP1 expression was deficient in advanced International Federation of Gynecology and Obstetrics stage, high-grade and myometrial invasive EEA. In EEA cell lines (Hec1A, Hec1B, RL952, and Ishikawa), the DUSP1 expression was substantially higher in Ishikawa cells than in other cell lines (P < 0.05). Knockdown of DUSP1 promoted Ishikawa cells proliferation, migration, and activation of mitogen-activated protein kinases/extracellular signal-regulated kinase (MAPK/Erk) pathway. MPA-induced DUSP1 expression and inhibited MAPK/Erk pathway in Ishikawa cells.

CONCLUSIONSOur data suggest that DUSP1 deficiency promotes EEA progression via MAPK/Erk pathway, which may be reversed by MPA, suggesting that DUSP1 may serve as a potential therapeutic target for the treatment of EEA.

Carcinoma, Endometrioid ; metabolism ; Cell Culture Techniques ; Cell Proliferation ; genetics ; physiology ; Dual-Specificity Phosphatases ; genetics ; metabolism ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Female ; Humans ; Mitogen-Activated Protein Kinases ; metabolism