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Abnormal processing of stressed replication forks by nucleases can cause fork collapse, genomic instability, and cell death. Despite its importance, it is poorly understood how the cell properly controls nucleases to prevent detrimental fork processing. Here, we report a signaling pathway that controls the activity of exonuclease Exo1 to prevent aberrant fork resection during replication stress. Our results indicate that replication stress elevates intracellular Ca2+ concentration ([Ca2+]i), leading to activation of CaMKK2 and the downstream kinase 5' AMP-activated protein kinase (AMPK). Following activation, AMPK directly phosphorylates Exo1 at serine 746 to promote 14-3-3 binding and inhibit Exo1 recruitment to stressed replication forks, thereby avoiding unscheduled fork resection. Disruption of this signaling pathway results in excessive ssDNA, chromosomal instability, and hypersensitivity to replication stress inducers. These findings reveal a link between [Ca2+]i and the replication stress response as well as a function of the Ca2+-CaMKK2-AMPK signaling axis in safeguarding fork structure to maintain genome stability.
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Proteínas Quinasas Activadas por AMP/genética , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/genética , Calcio/metabolismo , Enzimas Reparadoras del ADN/genética , Reparación del ADN , Replicación del ADN , Exodesoxirribonucleasas/genética , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Señalización del Calcio/genética , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Cromatina/química , Cromatina/metabolismo , Daño del ADN , Enzimas Reparadoras del ADN/metabolismo , ADN de Cadena Simple/genética , ADN de Cadena Simple/metabolismo , Exodesoxirribonucleasas/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Células HEK293 , Células HeLa , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Ratones , Osteoblastos/citología , Osteoblastos/metabolismo , Fosforilación , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
The Wnt/Wingless signaling pathway plays critical roles in metazoan development and energy metabolism, but its role in regulating lipid homeostasis remains not fully understood. Here, we report that the activation of canonical Wnt/Wg signaling promotes lipolysis while concurrently inhibiting lipogenesis and fatty acid ß-oxidation in both larval and adult adipocytes, as well as cultured S2R+ cells, in Drosophila. Using RNA-sequencing and CUT&RUN (Cleavage Under Targets & Release Using Nuclease) assays, we identified a set of Wnt target genes responsible for intracellular lipid homeostasis. Notably, active Wnt signaling directly represses the transcription of these genes, resulting in decreased de novo lipogenesis and fatty acid ß-oxidation, but increased lipolysis. These changes lead to elevated free fatty acids and reduced triglyceride (TG) accumulation in adipocytes with active Wnt signaling. Conversely, downregulation of Wnt signaling in the fat body promotes TG accumulation in both larval and adult adipocytes. The attenuation of Wnt signaling also increases the expression of specific lipid metabolism-related genes in larval adipocytes, wing discs, and adult intestines. Taken together, these findings suggest that Wnt signaling-induced transcriptional repression plays an important role in regulating lipid homeostasis by enhancing lipolysis while simultaneously suppressing lipogenesis and fatty acid ß-oxidation.
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Proteínas de Drosophila , Vía de Señalización Wnt , Animales , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Adipocitos/metabolismo , Movilización Lipídica , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Proteína Wnt1/metabolismo , Proteína Wnt1/genética , Lipólisis , Lipogénesis/genética , Triglicéridos/metabolismo , Metabolismo de los Lípidos/genética , Larva/metabolismo , Larva/genética , Transcripción Genética , HomeostasisRESUMEN
The manchette is a crucial transient structure involved in sperm development, with its composition and regulation still not fully understood. This study focused on investigating the roles of CAMSAP1 and CAMSAP2, microtubule (MT) minus-end binding proteins, in regulating manchette MTs, spermiogenesis, and male fertility. The loss of CAMSAP1, but not CAMSAP2, disrupts the well-orchestrated process of spermiogenesis, leading to abnormal manchette elongation and delayed removal, resulting in deformed sperm nuclei and tails resembling oligoasthenozoospermia symptoms. We investigated the underlying molecular mechanisms by purifying manchette assemblies and comparing them through proteomic analysis, and results showed that the absence of CAMSAP1 disrupted the proper localization of key proteins (CEP170 and KIF2A) at the manchette minus end, compromising its structural integrity and hindering MT depolymerization. These findings highlight the significance of maintaining homeostasis in manchette MT minus-ends for shaping manchette morphology during late spermiogenesis, offering insights into the molecular mechanisms underlying infertility and sperm abnormalities.
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Proteómica , Semen , Humanos , Masculino , Espermatogénesis/fisiología , Microtúbulos/metabolismo , FertilidadRESUMEN
Stomatal movement plays a critical role in plant immunity by limiting the entry of pathogens. OPEN STOMATA 1 (OST1) is a key component that mediates stomatal closure in plants, however, how OST1 functions in response to pathogens is not well understood. RECEPTOR-LIKE KINASE 902 (RLK902) phosphorylates BRASSINOSTEROID-SIGNALING KINASE 1 (BSK1) and positively modulates plant resistance. In this study, by a genome-wide phosphorylation analysis, we found that the phosphorylation of BSK1 and OST1 was missing in the rlk902 mutant compared with the wild-type plants, indicating a potential connection between the RLK902-BSK1 module and OST1-mediated stomatal closure. We showed that RLK902 and BSK1 contribute to stomatal immunity, as the stomatal closure induced by the bacterial pathogen Pto DC3000 was impaired in rlk902 and bsk1-1 mutants. Stomatal immunity mediated by RLK902 was dependent on BSK1 phosphorylation at Ser230, a key phosphorylation site for BSK1 functions. Several phosphorylation sites of OST1 were important for RLK902- and BSK1-mediated stomatal immunity. Interestingly, the phosphorylation of Ser171 and Ser175 in OST1 contributed to the stomatal immunity mediated by RLK902 but not by BSK1, while phosphorylation of OST1 at Ser29 and Thr176 residues was critical for BSK1-mediated stomatal immunity. Taken together, these results indicate that RLK902 and BSK1 contribute to disease resistance via OST1-mediated stomatal closure. This work revealed a new function of BSK1 in activating stomatal immunity, and the role of RLK902-BSK1 and OST1 module in regulating pathogen-induced stomatal movement.
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Photosynthesis and the biosynthesis of many important metabolites occur in chloroplasts. In these semi-autonomous organelles, the chloroplast genome encodes approximately 100 proteins. The remaining chloroplast proteins, close to 3,000, are encoded by nuclear genes whose products are translated in the cytosol and imported into chloroplasts. However, there is still no consensus on the composition of the protein import machinery including its motor proteins and on how newly imported chloroplast proteins are refolded. In this study, we have examined the function of orf2971, the largest chloroplast gene of Chlamydomonas reinhardtii. The depletion of Orf2971 causes the accumulation of protein precursors, partial proteolysis and aggregation of proteins, increased expression of chaperones and proteases, and autophagy. Orf2971 interacts with the TIC (translocon at the inner chloroplast envelope) complex, catalyzes ATP (adenosine triphosphate) hydrolysis, and associates with chaperones and chaperonins. We propose that Orf2971 is intimately connected to the protein import machinery and plays an important role in chloroplast protein quality control.
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Cloroplastos , Proteínas de Plantas , Núcleo Celular , Proteínas de Cloroplastos , Chaperonas Moleculares , Transporte de ProteínasRESUMEN
Endoreduplication, a process in which DNA replication occurs in the absence of mitosis, is found in all eukaryotic kingdoms, especially plants, where it is assumed to be important for cell growth and cell fate maintenance. However, a comprehensive understanding of the mechanism regulating endoreduplication is still lacking. We previously reported that UBIQUITIN-SPECIFIC PROTEASE14 (UBP14), encoded by DA3, acts upstream of CYCLIN-DEPENDENT KINASE B1;1 (CDKB1;1) to influence endoreduplication and cell growth in Arabidopsis thaliana. The da3-1 mutant possesses large cotyledons with enlarged cells due to high ploidy levels. Here, we identified a suppressor of da3-1 (SUPPRESSOR OF da3-1 6; SUD6), encoding CYCLIN-DEPENDENT KINASE G2 (CDKG2), which promotes endoreduplication and cell growth. CDKG2/SUD6 physically associates with CDKB1;1 in vivo and in vitro. CDKB1;1 directly phosphorylates SUD6 and modulates its stability. Genetic analysis indicated that SUD6 acts downstream of DA3 and CDKB1;1 to control ploidy level and cell growth. Thus, our study establishes a regulatory cascade for UBP14/DA3-CDKB1;1-CDKG2/SUD6-mediated control of endoreduplication and cell growth in Arabidopsis.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Ciclo Celular/genética , Quinasas Ciclina-Dependientes/genética , Endorreduplicación/genética , Ubiquitina/genéticaRESUMEN
Carbon metabolism is central to photosynthetic organisms and involves the coordinated operation and regulation of numerous proteins. In cyanobacteria, proteins involved in carbon metabolism are regulated by multiple regulators including the RNA polymerase sigma factor SigE, the histidine kinases Hik8, Hik31 and its plasmid-borne paralog Slr6041, and the response regulator Rre37. To understand the specificity and the cross-talk of such regulations, we simultaneously and quantitatively compared the proteomes of the gene knockout mutants for the regulators. A number of proteins showing differential expression in one or more mutants were identified, including four proteins that are unanimously upregulated or downregulated in all five mutants. These represent the important nodes of the intricate and elegant regulatory network for carbon metabolism. Moreover, serine phosphorylation of PII, a key signaling protein sensing and regulating in vivo carbon/nitrogen (C/N) homeostasis through reversible phosphorylation, is massively increased with a concomitant significant decrease in glycogen content only in the hik8-knockout mutant, which also displays impaired dark viability. An unphosphorylatable PII S49A substitution restored the glycogen content and rescued the dark viability of the mutant. Together, our study not only establishes the quantitative relationship between the targets and the corresponding regulators and elucidated their specificity and cross-talk but also unveils that Hik8 regulates glycogen accumulation through negative regulation of PII phosphorylation, providing the first line of evidence that links the two-component system with PII-mediated signal transduction and implicates them in the regulation of carbon metabolism.
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Carbono , Synechocystis , Fosforilación , Carbono/metabolismo , Proteómica , Synechocystis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Glucógeno/metabolismo , Nitrógeno , Regulación Bacteriana de la Expresión GénicaRESUMEN
The extremely dynamic life cycle of gap junction connections requires highly efficient intracellular trafficking system especially designed for gap junction proteins, but the underlying mechanisms are largely unknown. Here, we identified that the COPII-associated proteins ERGIC2 (ER-Golgi intermediate compartment) and ERGIC3 are specifically required for the efficient intracellular transport of gap junction proteins in both Caenorhabditis elegans and mice. In the absence of Ergic2 or Ergic3, gap junction proteins accumulate in the ER and Golgi apparatus and the size of endogenous gap junction plaques is reduced. Knocking out the Ergic2 or Ergic3 in mice results in heart enlargement and cardiac malfunction accompanied by reduced number and size of connexin 43 (Cx43) gap junctions. Invertebrates' gap junction protein innexins share no sequence similarity with vertebrates' connexins. However, ERGIC2 and ERGIC3 could bind to gap junction proteins in both worms and mice. Characterization of the highly specialized roles of ERGIC2 and ERGIC3 in metazoans reveals how the early secretory pathway could be adapted to facilitate the efficient transport for gap junction proteins in vivo.
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Conexinas , Aparato de Golgi , Animales , Conexinas/metabolismo , Uniones Comunicantes/metabolismo , Aparato de Golgi/metabolismo , Ratones , Vías Secretoras , Proteínas de Transporte VesicularRESUMEN
T-cell immunoglobulin and mucin domain-containing molecule 4 (Tim-4) is an immune checkpoint molecule, which involves in numerous inflammatory diseases. Tim-4 is mainly expressed on antigen presenting cells. However, increasing evidences have shown that Tim-4 is also expressed on natural killer T (NKT) cells. The role of Tim-4 in maintaining NKT cell homeostasis and function remains unknown. In this study, we explored the effect of Tim-4 on NKT cells in acute liver injury. This study found that Tim-4 expression on hepatic NKT cells was elevated during acute liver injury. Tim-4 deficiency enhanced IFN-γ, TNF-α expression while impaired IL-4 production in NKT cells. Loss of Tim-4 drove NKT cell effector lineages to be skewed to NKT1 subset. Furthermore, Tim-4 KO mice were more susceptible to α-GalCer challenge. In conclusion, our findings indicate that Tim-4 plays an important role in regulating homeostasis and function of NKT cells in acute liver injury. Therefore, Tim-4 might become a new regulator of NKT cells and a potential target for the therapy of acute hepatitis.
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Glycosyltransferases (GTs) are enzymes that transfer sugars to various targets. They play important roles in diverse biological processes, including photosynthesis, cell motility, exopolysaccharide biosynthesis, and lipid metabolism; however, their involvement in regulating carbon metabolism in Synechocystis sp. PCC 6803 has not been reported. We identified a novel GT protein, Slr1064, involved in carbon metabolism. The effect of slr1064 deletion on the growth of Synechocystis cells and functional mechanisms of Slr1064 on carbon metabolism were thoroughly investigated through physiological, biochemistry, proteomic, and metabolic analyses. We found that this GT, which is mainly distributed in the membrane compartment, is essential for the growth of Synechocystis under heterotrophic and mixotrophic conditions, but not under autotrophic conditions. The deletion of slr1064 hampers the turnover rate of Gap2 under mixotrophic conditions and disrupts the assembly of the PRK/GAPDH/CP12 complex under dark culture conditions. Additionally, UDP-GlcNAc, the pivotal metabolite responsible for the O-GlcNAc modification of GAPDH, is downregulated in the Δslr1064. Our work provides new insights into the role of GTs in carbon metabolism in Synechocystis and elucidate the mechanism by which carbon metabolism is regulated in this important model organism.
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Proteínas Bacterianas , Carbono , Glicosiltransferasas , Synechocystis , Uridina Difosfato N-Acetilglucosamina , Synechocystis/metabolismo , Synechocystis/genética , Synechocystis/crecimiento & desarrollo , Carbono/metabolismo , Glicosiltransferasas/metabolismo , Glicosiltransferasas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Uridina Difosfato N-Acetilglucosamina/metabolismo , Regulación Bacteriana de la Expresión Génica , Eliminación de GenRESUMEN
Endoplasmic reticulum-associated degradation (ERAD) is known to regulate plant responses to diverse stresses, yet its underlying molecular mechanisms and links to various stress signaling pathways are poorly understood. Here, we show that the ERAD component ubiquitin-conjugating enzyme UBC32 positively regulates drought tolerance in Arabidopsis thaliana by targeting the aquaporins PIP2;1 and PIP2;2 for degradation. Furthermore, we demonstrate that the RING-type ligase Rma1 acts together with UBC32 and that the E2 activity of UBC32 is essential for the ubiquitination of Rma1. This complex ubiquitinates a phosphorylated form of PIP2;1 at Lys276 to promote its degradation, thereby enhancing plant drought tolerance. Extending these molecular insights into crops, we show that overexpression of Arabidopsis UBC32 also improves drought tolerance in rice (Oryza sativa). Thus, beyond uncovering the molecular basis of an ERAD-regulated stress response, our study suggests multiple potential strategies for engineering crops with improved drought tolerance.
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Acuaporinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiología , Oryza/fisiología , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ácido Abscísico/metabolismo , Acuaporinas/genética , Proteínas de Arabidopsis/genética , Deshidratación , Sequías , Degradación Asociada con el Retículo Endoplásmico , Lisina/metabolismo , Espectrometría de Masas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Oryza/genética , Oryza/crecimiento & desarrollo , Fosforilación , Plantas Modificadas Genéticamente , Estabilidad Proteica , Enzimas Ubiquitina-Conjugadoras/genética , UbiquitinaciónRESUMEN
Background: The accurate identification and diagnosis of secondary hypertension is critical,especially while cardiovascular heart disease continues to be the leading cause of death. To develop a big data intelligence platform for secondary hypertension using electronic medical records to contribute to future basic and clinical research. Methods: Using hospital data, the platform, named Hypertension DATAbase at Urumchi (UHDATA), included patients diagnosed with hypertension at the People's Hospital of Xinjiang Uygur Autonomous Region since December 2004. The electronic data acquisition system, the database synchronization technology, and data warehouse technology (extract-transform-load, ETL) for the scientific research big data platform were used to synchronize and extract the data from each business system in the hospital. Standard data elements were established for the platform, including demographic and medical information. To facilitate the research, the database was also linked to the sample database system, which includes blood samples, urine specimens, and tissue specimens. Results: From December 17, 2004, to August 31, 2022, a total of 295,297 hypertensive patients were added to the platform, with 53.76% being males, with a mean age of 59 years, and 14% with secondary hypertension. However, 75,802 patients visited the Hypertension Center at our hospital, with 43% (32,595 patients) being successfully diagnosed with secondary hypertension. The database contains 1458 elements, with an average fill rate of 90%. The database can continuously include the data for new hypertensive patients and add new data for existing hypertensive patients, including post-discharge follow-up information, and the database updates every 2 weeks. Presently, some studies that are based on the platform have been published. Conclusions: Using computer information technology, we developed and implemented a big database of dynamically updating electronic medical records for patients with hypertension, which is helpful in promoting future research on secondary hypertension.
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The size of lipid droplets varies greatly in vivo and is determined by both intrinsic and extrinsic factors. From an RNAi screen in Drosophila, we found that knocking down subunits of COP9 signalosome (CSN) results in enlarged lipid droplets under high-fat, but not normal, conditions. We identified CG2064, a retinol dehydrogenase (RDH) homolog, as the proteasomal degradation target of CSN in regulating lipid droplet size. RDH/CG2064 interacts with the lipid droplet-resident protein Plin2 and the RDH/CG2064-Plin2 axis acts to reduce the overall level and lipid droplet localization of Bmm/ATGL lipase. This axis is important for larval survival under prolonged starvation. Thus, we discovered an RDH-Plin2 axis modulates lipid droplet size.
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Drosophila , Lipasa , Gotas Lipídicas , Perilipina-2 , Animales , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Larva/genética , Larva/metabolismo , Lipasa/genética , Lipasa/metabolismo , Gotas Lipídicas/metabolismo , Perilipina-2/metabolismoRESUMEN
Sodium carbonate-promoted facile synthesis of 5-amino-1,2,4-thiadiazoles and 5-amino-1,2,4-selenadiazoles with elemental sulfur and selenium, respectively, was developed. This method was carried out with O2 in the air as the green oxidant, and it has several advantages, including low cost, low toxicity, and stable sulfur and selenium sources, good to excellent yields with water as the sole byproduct, simple operation, and a broad substrate scope. Preliminary mechanistic studies indicate that the formation of the 1,2,4-thiadiazole ring and the 1,2,4-selenadiazole ring undergoes different processes.
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BACKGROUND: Invasive pneumococcal disease (IPD) is a significant health concern in children worldwide. In this study, we aimed to analyze the clinical features, antibiotic resistance, and risk variables for poor outcomes in patients with IPD in Hangzhou. METHODS: A retrospective single-centre study was performed using the pediatric intensive care (PIC) database from 2010 to 2018. The clinical characteristics, laboratory data, antimicrobial resistance, and risk factors for in-hospital mortality and sepsis in patients with IPD in intensive care units (ICUs) were analyzed systematically. RESULTS: A total of 178 IPD patients were included in the study. The majority of the IPD children were 2-10 years old. Antimicrobial resistance tests of S. pneumoniae isolates revealed high resistance to erythromycin, tetracycline and compound sulfamethoxazole (SMZ-Co). All the isolates were sensitive to vancomycin, linezolid, moxifloxacin, telithromycin, ofloxacin, and levofloxacin. IPD patients may experience poor outcomes, including death and sepsis. The in-hospital mortality was 3.93%, and 34.27% of patients suffered from sepsis. Temperature (OR 3.80, 95% CI 1.62-8.87; P = 0.0021), Partial Pressure of Oxygen in Arterial Blood (PaO2) (OR 0.99, 95% CI 0.98-1.00; P = 0.0266), and albumin (OR 0.89, 95% CI 0.80-0.99; P = 0.0329) were found to be independent risk factors for sepsis in children with IPD. CONCLUSION: Pediatric IPD deserves attention in China. Appropriate surveillance and antibiotic selection are crucial in managing resistant strains. Early identification of high-risk individuals with risk factors contributes to the development of appropriate treatment strategies.
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Antibacterianos , Mortalidad Hospitalaria , Infecciones Neumocócicas , Streptococcus pneumoniae , Humanos , China/epidemiología , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/mortalidad , Infecciones Neumocócicas/epidemiología , Niño , Masculino , Factores de Riesgo , Estudios Retrospectivos , Femenino , Preescolar , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Lactante , Pruebas de Sensibilidad Microbiana , Sepsis/microbiología , Sepsis/tratamiento farmacológico , Sepsis/mortalidad , Sepsis/epidemiología , Adolescente , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Farmacorresistencia BacterianaRESUMEN
Skin photoaging affects appearance and is associated with a variety of skin diseases, even skin cancer. Therefore, the prevention and treatment of skin photoaging is very important. However, there is a lack of effective evaluation methods, so it is an urgent problem to explore a comprehensive, non-invasive and in vivo evaluation method. Adipose-derived mesenchymal stem cells (ADSCs) are widely used to improve skin conditions as easier to obtain and positive effects. Recently, as the development of ultrasound technology, skin ultrasound has been widely used. Changes in skin layer and structure can be observed by high-frequency ultrasound (HFUS). In addition, Shear wave elastography (SWE) technology can be used to monitor the change of skin hardness. However, it is necessary to further explore the ultrasound parameters in interpreting histological changes. We simulate the progression and treatment process of human skin photoaging by using UVB-induced nude mice skin photoaging model and ADSCs injection. The analysis of the degree and therapeutic effect of skin photoaging was conducted by HFUS, SWE and to verify with histopathology. Our study aims to clarify the value of HFUS combined SWE techniques in evaluating the degree and therapeutic efficacy of skin photoaging, which provides theoretical basis for diagnosis and treatment evaluation systems.
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Células Madre Mesenquimatosas , Ratones Desnudos , Envejecimiento de la Piel , Piel , Rayos Ultravioleta , Animales , Envejecimiento de la Piel/efectos de la radiación , Células Madre Mesenquimatosas/citología , Humanos , Piel/efectos de la radiación , Piel/patología , Tejido Adiposo/citología , Diagnóstico por Imagen de Elasticidad , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones , FemeninoRESUMEN
Ascorbate peroxidase (APEX)-based proximity labeling coupled with mass spectrometry has a great potential for spatiotemporal identification of proteins proximal to a protein complex of interest. Using this approach is feasible to define the proteome neighborhood of important protein complexes in a popular photosynthetic model cyanobacterium Synechocystis sp. PCC6803 (hereafter named as Synechocystis). To this end, we developed a robust workflow for APEX2-based proximity labeling in Synechocystis and used the workflow to identify proteins proximal to the photosystem II (PS II) oxygen evolution complex (OEC) through fusion APEX2 with a luminal OEC subunit, PsbO. In total, 38 integral membrane proteins (IMPs) and 93 luminal proteins were identified as proximal to the OEC. A significant portion of these proteins are involved in PS II assembly, maturation, and repair, while the majority of the rest were not previously implicated with PS II. The IMPs include subunits of PS II and cytochrome b6/f, but not of photosystem I (except for PsaL) and ATP synthases, suggesting that the latter two complexes are spatially separated from the OEC with a distance longer than the APEX2 labeling radius. Besides, the topologies of six IMPs were successfully predicted because their lumen-facing regions exclusively contain potential APEX2 labeling sites. The luminal proteins include 66 proteins with a predicted signal peptide and 57 proteins localized also in periplasm, providing important targets to study the regulation and selectivity of protein translocation. Together, we not only developed a robust workflow for the application of APEX2-based proximity labeling in Synechocystis and showcased the feasibility to define the neighborhood proteome of an important protein complex with a short radius but also discovered a set of the proteins that potentially interact with and regulate PS II structure and function.
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Complejo de Proteína del Fotosistema II , Synechocystis , Complejo de Proteína del Fotosistema II/metabolismo , Proteoma/metabolismo , Oxígeno/metabolismo , Complejo de Proteína del Fotosistema I/metabolismo , Synechocystis/metabolismoRESUMEN
Brain development and function are governed by precisely regulated protein expressions in different regions. To date, multiregional brain proteomes have been systematically analyzed only for adult human and mouse brains. To understand the underpinnings of brain development and function, we generated proteomes from six regions of the postnatal brain at three developmental stages of domestic dogs (Canis familiaris), which are special among animals in terms of their remarkable human-like social cognitive abilities. Quantitative analysis of the spatiotemporal proteomes identified region-enriched synapse types at different developmental stages and differential myelination progression in different brain regions. Through integrative analysis of inter-regional expression patterns of orthologous proteins and genome-wide cis-regulatory element frequencies, we found that proteins related with myelination and hippocampus were highly correlated between dog and human but not between mouse and human, although mouse is phylogenetically closer to human. Moreover, the global expression patterns of neurodegenerative disease and autism spectrum disorder-associated proteins in dog brain more resemble human brain than in mouse brain. The high similarity of myelination and hippocampus-related pathways in dog and human at both proteomic and genetic levels may contribute to their shared social cognitive abilities. The inter-regional expression patterns of disease-associated proteins in the brain of different species provide important information to guide mechanistic and translational study using appropriate animal models.
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Trastorno del Espectro Autista , Enfermedades Neurodegenerativas , Adulto , Animales , Encéfalo , Perros , Humanos , Ratones , Proteoma , ProteómicaRESUMEN
OBJECTIVE: To investigate the potential affective factors of depressive symptoms in patients with hypertension and explore the protective effects of physical activity. METHODS: 211 hypertensive patients aged over 18 years were consecutively recruited. All patients completed a self-designed questionnaire and the Hospital Anxiety and Depression Scale (HADS) to assess the coexistence of depressive symptoms, and psychiatrists were invited to diagnose depression when necessary. Full-night polysomnography was performed to detect the sleep pattern. The association between sleep structure and depressive symptoms was tested by using logistic regression analysis, and contributing factors as well as the effect of physical activity were assessed among patients with and without depressive symptoms. RESULTS: Of the 211 subjects, 33.6% of cases were coexistent with depressive symptoms. Female gender [OR (95%CI): 2.83 (1.44-5.57), P = 0.003) and the greater percentage of REM stage [OR (95%CI): 1.09 (1.01-1.18), P = 0.024] were the risk factors of depressive symptoms, while doing physical activity showed as the protective factor. Patients with REM stage ≥ 20% showed a higher score on HADS-D than those with REM stage < 20% [(4.9 ± 3.8) vs. (3.7 ± 3.1), P = 0.018]. Compared to individuals who never did physical activity, those who did physical activity 1-2 times per week and ≥ 3 times per week had a 52% and 62% risk reduction in depressive symptoms respectively. Patients who did physical activity had lower levels of high-sensitivity C-reactive protein (hs-CRP) compared to those who never did physical activity. CONCLUSION: Female gender and a higher percentage of REM stage are risk factors for depressive symptoms in hypertension, while physical activity may benefit depressive symptoms by reducing serum levels of hs-CRP.
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Stomata in leaves regulate gas exchange between the plant and its atmosphere. Various environmental stimuli elicit abscisic acid (ABA); ABA leads to phosphoactivation of slow anion channel 1 (SLAC1); SLAC1 activity reduces turgor pressure in aperture-defining guard cells; and stomatal closure ensues. We used electrophysiology for functional characterizations of Arabidopsis thaliana SLAC1 (AtSLAC1) and cryoelectron microscopy (cryo-EM) for structural analysis of Brachypodium distachyon SLAC1 (BdSLAC1), at 2.97-Å resolution. We identified 14 phosphorylation sites in AtSLAC1 and showed nearly 330-fold channel-activity enhancement with 4 to 6 of these phosphorylated. Seven SLAC1-conserved arginines are poised in BdSLAC1 for regulatory interaction with the N-terminal extension. This BdSLAC1 structure has its pores closed, in a basal state, spring loaded by phenylalanyl residues in high-energy conformations. SLAC1 phosphorylation fine-tunes an equilibrium between basal and activated SLAC1 trimers, thereby controlling the degree of stomatal opening.