ABSTRACT
Mammalian Ste-20-like Kinases 1 and 2 (MST1/2) are core serine-threonine kinases of the Hippo pathway regulating several cellular processes, including cell cycle arrest and cell death. Here, we discovered a novel alternative splicing variant of the MST2 encoding gene, STK3, in malignant cells and tumor datasets. This variant, named STK3∆7 or MST2∆7 (for mRNA or protein, respectively), resulted from the skipping of exon 7. MST2∆7 exhibited increased ubiquitylation and interaction with the E3 ubiquitin-protein ligase CHIP compared to the full-length protein (MST2FL). Exon 7 in STK3 encodes a segment within the kinase domain, and its exclusion compromised MST2 interaction with and phosphorylation of MOB, a major MST1/2 substrate. Nevertheless, MST2∆7 was capable of interacting with MST1 and MST2FL. Unlike MST2FL, overexpression of MST2∆7 did not lead to increased cell death and growth arrest. Strikingly, we observed the exclusion of STK3 exon 7 in 3.2-15% of tumor samples from patients of several types of cancer, while STK3∆7 was seldomly found in healthy tissues. Our study identified a novel STK3 splicing variant with loss of function and the potential to disturb tissue homeostasis by impacting on MST2 activities in the regulation of cell death and quiescence.
Subject(s)
Alternative Splicing , Cell Proliferation , Protein Serine-Threonine Kinases , Serine-Threonine Kinase 3 , Humans , Adaptor Proteins, Signal Transducing , Cell Line, Tumor , Exons/genetics , HEK293 Cells , Hepatocyte Growth Factor/genetics , Hepatocyte Growth Factor/metabolism , Neoplasms/genetics , Neoplasms/pathology , Neoplasms/metabolism , Phosphorylation , Protein Isoforms/genetics , Protein Isoforms/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Serine-Threonine Kinase 3/genetics , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination/geneticsABSTRACT
The PKC-related kinases (PRKs, also termed PKNs) are important in cell migration, cancer, hepatitis C infection, and nutrient sensing. They belong to a group of protein kinases called AGC kinases that share common features like a C-terminal extension to the catalytic domain comprising a hydrophobic motif. PRKs are regulated by N-terminal domains, a pseudosubstrate sequence, Rho-binding domains, and a C2 domain involved in inhibition and dimerization, while Rho and lipids are activators. We investigated the allosteric regulation of PRK2 and its interaction with its upstream kinase PDK1 using a chemical biology approach. We confirmed the phosphoinositide-dependent protein kinase 1 (PDK1)-interacting fragment (PIF)-mediated docking interaction of PRK2 with PDK1 and showed that this interaction can be modulated allosterically. We showed that the polypeptide PIFtide and a small compound binding to the PIF-pocket of PRK2 were allosteric activators, by displacing the pseudosubstrate PKL region from the active site. In addition, a small compound binding to the PIF-pocket allosterically inhibited the catalytic activity of PRK2. Together, we confirmed the docking interaction and allostery between PRK2 and PDK1 and described an allosteric communication between the PIF-pocket and the active site of PRK2, both modulating the conformation of the ATP-binding site and the pseudosubstrate PKL-binding site. Our study highlights the allosteric modulation of the activity and the conformation of PRK2 in addition to the existence of at least two different complexes between PRK2 and its upstream kinase PDK1. Finally, the study highlights the potential for developing allosteric drugs to modulate PRK2 kinase conformations and catalytic activity.
Subject(s)
Protein Kinase C , Pyruvate Dehydrogenase Acetyl-Transferring Kinase , Humans , Allosteric Regulation , Protein Kinase C/metabolism , Protein Kinase C/genetics , Protein Kinase C/chemistry , Pyruvate Dehydrogenase Acetyl-Transferring Kinase/metabolism , Pyruvate Dehydrogenase Acetyl-Transferring Kinase/genetics , Catalytic Domain , Molecular Docking Simulation , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/chemistry , 3-Phosphoinositide-Dependent Protein Kinases/metabolism , 3-Phosphoinositide-Dependent Protein Kinases/genetics , 3-Phosphoinositide-Dependent Protein Kinases/chemistry , Protein BindingABSTRACT
Introduction: Understanding the genetic factors contributing to variations in bone mineral density (BMD) and vitamin D could provide valuable insights into the pathogenesis of osteoporosis. This study aimed to evaluate the association of single nucleotide variants in MARK3 (rs11623869), PLCB4 (rs6086746), and GEMIN2 (rs2277458) with BMD in Mexican women. Methods: The gene-gene interaction was evaluated in these variants in serum 25(OH)D levels and BMD. A genetic risk score (GRS) was created on the basis of the three genetic variants. Genotyping was performed using predesigned TaqMan assays. Results: A significant association was found between the rs6086746-A variant and BMD at the total hip, femoral neck, and lumbar spine, in women aged 45 years or older. However, no association was observed between the variants rs11623869 and rs2277458. The rs11623869 × rs2277458 interaction was associated with total hip (p=0.002) and femoral neck BMD (p=0.013). Similarly, for vitamin D levels, we observed an interaction between the variants rs6086746 × rs2277458 (p=0.021). GRS revealed a significant association with total hip BMD (p trend=0.003) and femoral neck BMD (p trend=0.006), as well as increased vitamin D levels (p trend=0.0003). These findings provide evidence of the individual and joint effect of the MARK3, PLCB4, and GEMIN2 variants on BMD and serum vitamin D levels in Mexican women. Discussion: This knowledge could help to elucidate the interaction mechanism between BMD-related genetic variants and 25OHD, contributing to the determination of the pathogenesis of osteoporosis and its potential implications during early interventions.
Subject(s)
Bone Density , Vitamin D , Adult , Aged , Female , Humans , Middle Aged , Bone Density/genetics , Genetic Predisposition to Disease , Genotype , GTP-Binding Proteins/genetics , Mexico , Osteoporosis/genetics , Osteoporosis/blood , Polymorphism, Single Nucleotide , Protein Serine-Threonine Kinases/genetics , Vitamin D/blood , Vitamin D/analogs & derivativesABSTRACT
Colletotrichum graminicola, the causal agent of maize leaf anthracnose and stalk rot, differentiates a pressurized infection cell called an appressorium in order to invade the epidermal cell, and subsequently forms biotrophic and necrotrophic hyphae to colonize the host tissue. While the role of force in appressorial penetration is established (Bechinger et al., 1999), the involvement of cell wall-degrading enzymes (CWDEs) in this process and in tissue colonization is poorly understood, due to the enormous number and functional redundancy of these enzymes. The serine/threonine protein kinase gene SNF1 identified in Sucrose Non-Fermenting yeast mutants mediates de-repression of catabolite-repressed genes, including many genes encoding CWDEs. In this study, we identified and functionally characterized the SNF1 homolog of C. graminicola. Δsnf1 mutants showed reduced vegetative growth and asexual sporulation rates on media containing polymeric carbon sources. Microscopy revealed reduced efficacies in appressorial penetration of cuticle and epidermal cell wall, and formation of unusual medusa-like biotrophic hyphae by Δsnf1 mutants. Severe and moderate virulence reductions were observed on intact and wounded leaves, respectively. Employing RNA-sequencing we show for the first time that more than 2,500 genes are directly or indirectly controlled by Snf1 in necrotrophic hyphae of a plant pathogenic fungus, many of which encode xylan- and cellulose-degrading enzymes. The data presented show that Snf1 is a global regulator of gene expression and is required for full virulence.
Subject(s)
Colletotrichum , Zea mays , Zea mays/genetics , Virulence/genetics , Cell Wall/genetics , Cell Wall/metabolism , Saccharomyces cerevisiae/genetics , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Plant Diseases/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolismABSTRACT
INTRODUCTION: Lung cancer is one of the most prevalent cancers and the leading cause of cancer death. Advanced non-small cell lung cancer (aNSCLC) patients frequently harbor mutations that impact their survival outcomes. There are limited data regarding the prognostic and predictive significance of these mutations on survival outcomes in the real-world setting. METHODS: This observational retrospective study analyzed de-identified electronic medical records from the Flatiron Health Clinico-Genomic and FoundationCore® databases to identify patients with aNSCLC who initiated first-line immune checkpoint inhibitors (ICI; alone or in combination) or chemotherapy under routine care between 2016 and 2021. The primary objectives were to assess the prevalence of non-actionable mutations and to determine their association with overall survival (OS). Real-world progression-free survival (rwPFS) and real-world response (rwR) were investigated as secondary exploratory outcomes. RESULTS: Based on an assessment of 185 non-actionable mutations in 2999 patients, the most prevalent mutations were TP53 (70%), KRAS (42%), CDKN2A/B (31%), and STK11 (21%). STK11, KEAP1, and CDKN2A/B mutations were significantly associated with lower rwR, shorter rwPFS and OS. KRAS mutations were clinically associated with shorter rwPFS in CIT-treated patients. Subgroup analysis revealed that fast progressors were significantly more likely to harbor STK11, KEAP1, and CDKN2A/B mutations. Accordingly, long-term survivors (LTS) showed a significantly lower prevalence of these mutations. CONCLUSION: Our results provide evidence on the prognostic value of STK11, KEAP1, and CDKN2A/B mutations in patients with aNSCLC. Further research is required to better understand the implications of these findings on patient management and future trial design and treatment selection.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Mutation , Humans , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/mortality , Lung Neoplasms/drug therapy , Retrospective Studies , Male , Female , Prognosis , Aged , Middle Aged , Protein Serine-Threonine Kinases/genetics , AMP-Activated Protein Kinase Kinases , Kelch-Like ECH-Associated Protein 1/genetics , Immune Checkpoint Inhibitors/therapeutic use , Cyclin-Dependent Kinase Inhibitor p16/genetics , Progression-Free Survival , Proto-Oncogene Proteins p21(ras)/genetics , Tumor Suppressor Protein p53/genetics , Aged, 80 and over , Adult , Survival RateABSTRACT
Kidney-specific with-no-lysine kinase 1 (KS-WNK1) is an isoform of WNK1 kinase that is predominantly found in the distal convoluted tubule of the kidney. The precise physiological function of KS-WNK1 remains unclear. Some studies have suggested that it could play a role in regulating potassium renal excretion by modulating the activity of the Na+-Cl- cotransporter (NCC). However, changes in the potassium diet from normal to high failed to reveal a role for KS-WNK1, but under a normal-potassium diet, the expression of KS-WNK1 is negligible. It is only detectable when mice are exposed to a low-potassium diet. In this study, we investigated the role of KS-WNK1 in regulating potassium excretion under extreme changes in potassium intake. After following a zero-potassium diet (0KD) for 10 days, KS-WNK1-/- mice had lower plasma levels of K+ and Cl- while exhibiting higher urinary excretion of Na+, Cl-, and K+ compared with KS-WNK1+/+ mice. After 10 days of 0KD or normal-potassium diet (NKD), all mice were challenged with a high-potassium diet (HKD). Plasma K+ levels markedly increased after the HKD challenge only in mice previously fed with 0KD, regardless of genotype. KSWNK1+/+ mice adapt better to HKD challenge than KS-WNK1-/- mice after a potassium-retaining state. The difference in the phosphorylated NCC-to-NCC ratio between KS-WNK1+/+ and KS-WNK1-/- mice after 0KD and HKD indicates a role for KS-WNK1 in both NCC phosphorylation and dephosphorylation. These observations show that KS-WNK1 helps the distal convoluted tubule to respond to extreme changes in potassium intake, such as those occurring in wildlife.NEW & NOTEWORTHY The findings of this study demonstrate that kidney-specific with-no-lysine kinase 1 plays a role in regulating urinary electrolyte excretion during extreme changes in potassium intake, such as those occurring in wildlife. .
Subject(s)
Mice, Knockout , Potassium, Dietary , WNK Lysine-Deficient Protein Kinase 1 , Animals , Male , Mice , Kidney/metabolism , Kidney Tubules, Distal/metabolism , Mice, Inbred C57BL , Phosphorylation , Potassium/urine , Potassium/metabolism , Potassium/blood , Potassium, Dietary/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Renal Elimination , Solute Carrier Family 12, Member 3/metabolism , Solute Carrier Family 12, Member 3/genetics , WNK Lysine-Deficient Protein Kinase 1/metabolism , WNK Lysine-Deficient Protein Kinase 1/genetics , FemaleABSTRACT
Marfan syndrome (MFS) is a multisystem genetic disorder with over 3000 mutations described in the fibrillin 1 (FBN1) gene. Like MFS, other connective tissue disorders also require a deeper understanding of the phenotype-genotype relationship due to the complexity of the clinical presentation, where diagnostic criteria often overlap. Our objective was to identify mutations in patients with connective tissue disorders using a genetic multipanel and to analyze the genotype-phenotype associations in a cohort of Mexican patients. We recruited 136 patients with MFS and related syndromes from the National Institute of Cardiology. Mutations were identified using next-generation sequencing (NGS). To examine the correlation between mutation severity and severe cardiovascular conditions, we focused on patients who had undergone Bentall-de Bono surgery or aortic valve repair. The genetic data obtained allowed us to reclassify the initial clinical diagnosis across various types of connective tissue disorders. The transforming growth factor beta receptor 2 (TGFBR2) rs79375991 mutation was found in 10 out of 16 (63%) Loeys-Dietz patients. We observed a high prevalence (65%) of more severe mutations, such as frameshift indels and stop codons, among patients requiring invasive treatments like aortic valve-sparing surgery, Bentall and de Bono procedures, or aortic valve replacement due to severe cardiovascular injury. Although our study did not achieve precise phenotype-genotype correlations, it underscores the importance of a multigenetic panel evaluation. This could pave the way for a more comprehensive diagnostic approach and inform medical and surgical treatment decision-making.
Subject(s)
Cardiovascular Diseases , Connective Tissue Diseases , Marfan Syndrome , Humans , Marfan Syndrome/diagnosis , Receptors, Transforming Growth Factor beta/genetics , Protein Serine-Threonine Kinases/genetics , Fibrillin-1/genetics , Connective TissueABSTRACT
OBJECTIVE: This study aimed to investigate whether homeodomain interacting protein kinase 2 (HIPK2) polymorphism is associated with renal stone formation in a Turkish population. MATERIALS AND METHODS: A total of 129 patients with calcium nephrolithiasis and 67 sex- and age-matched healthy controls were enrolled in the study. Blood samples were collected into EDTA tubes. The DNA of patients was extracted using a QIAsymphony® automated DNA isolation system. The Chi-square test was applied in the comparisons between the patient and control groups in respect of the differences in the genotype and allele frequencies. RESULTS: No statistically significant difference was found between the groups in terms of single nucleotide polymorphism (SNP) incidence in single allele and double alleles in the rs2058265 and rs6464214 regions (p = 0.13 and 0.37, respectively). The SNP incidence in double alleles in nephrolithiasis patients at rs7456421 was statistically significantly lower than in the control group (p = 0.001). CONCLUSION: Distributions of the genotype and allele of the three polymorphisms (rs2058265, rs6464214, and rs745642 in HIPK2) were not associated with an increased risk of kidney stone in this Turkish population.
OBJETIVO: Investigar si el polimorfismo de la proteína cinasa 2 que interactúa con el homeodominio (HIPK2) está asociado con la formación de cálculos renales en una población turca. MÉTODO: Se inscribieron en el estudio 129 pacientes con nefrolitiasis cálcica y 67 sujetos control sanos, emparejados por sexo y edad. Las muestras de sangre se recogieron en tubos con EDTA. El ADN de los pacientes se extrajo mediante un sistema de aislamiento de ADN automatizado QIAsymphony®. Se aplicó la prueba χ2 en las comparaciones entre los grupos de pacientes y control con respecto a las diferencias de las frecuencias genotípicas y alélicas. RESULTADOS: No se encontraron diferencias estadísticamente significativas entre los grupos en términos de incidencia de polimorfismo de nucleótido simple (PNS) en alelo simple y alelo doble en las regiones rs2058265 y rs6464214 (p = 0.13 y 0.37, respectivamente). La incidencia de PNS en alelos dobles en pacientes con nefrolitiasis en rs7456421 fue menor que en el grupo control, con una diferencia estadísticamente significativa (p = 0.001). CONCLUSIONES: Las distribuciones de genotipo y alelo de los tres polimorfismos (rs2058265, rs6464214 y rs745642 en HIPK2) no se asociaron con un mayor riesgo de cálculos renales en esta población turca.
Subject(s)
Kidney Calculi , Humans , Kidney Calculi/genetics , Alleles , Genotype , Polymorphism, Single Nucleotide , Carrier Proteins , Protein Serine-Threonine Kinases/geneticsABSTRACT
Type 1 conventional dendritic cells (cDC1s) are leukocytes competent to coordinate antiviral immunity, and thus, the intracellular mechanisms controlling cDC1 function are a matter of intense research. The unfolded protein response (UPR) sensor IRE1 and its associated transcription factor XBP1s control relevant functional aspects in cDC1s including antigen cross-presentation and survival. However, most studies connecting IRE1 and cDC1 function are undertaken in vivo. Thus, the aim of this work is to elucidate whether IRE1 RNase activity can also be modeled in cDC1s differentiated in vitro and reveal the functional consequences of such activation in cells stimulated with viral components. Our data show that cultures of optimally differentiated cDC1s recapitulate several features of IRE1 activation noticed in in vivo counterparts and identify the viral analog Poly(I:C) as a potent UPR inducer in the lineage. In vitro differentiated cDC1s display constitutive IRE1 RNase activity and hyperactivate IRE1 RNase upon genetic deletion of XBP1s, which regulates production of the proinflammatory cytokines IL-12p40, TNF-α and IL-6, Ifna and Ifnb upon Poly(I:C) stimulation. Our results show that a strict regulation of the IRE1/XBP1s axis regulates cDC1 activation to viral agonists, expanding the scope of this UPR branch in potential DC-based therapies.
Subject(s)
Protein Serine-Threonine Kinases , Unfolded Protein Response , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Gene Expression Regulation , Transcription Factors/metabolism , Ribonucleases/metabolismABSTRACT
In cancer, activation of the IRE1/XBP1s axis of the unfolded protein response (UPR) promotes immunosuppression and tumor growth, by acting in cancer cells and tumor infiltrating immune cells. However, the role of IRE1/XBP1s in dendritic cells (DCs) in tumors, particularly in conventional type 1 DCs (cDC1s) which are cellular targets in immunotherapy, has not been fully elucidated. Here, we studied the role of IRE1/XBP1s in subcutaneous B16/B78 melanoma and MC38 tumors by generating loss-of-function models of IRE1 and/or XBP1s in DCs or in cDC1s. Data show that concomitant deletion of the RNase domain of IRE1 and XBP1s in DCs and cDC1s does not influence the kinetics of B16/B78 and MC38 tumor growth or the effector profile of tumor infiltrating T cells. A modest effect is observed in mice bearing single deletion of XBP1s in DCs, which showed slight acceleration of melanoma tumor growth and dysfunctional T cell responses, however, this effect was not recapitulated in animals lacking XBP1 only in cDC1s. Thus, evidence presented here argues against a general pro-tumorigenic role of the IRE1/XBP1s pathway in tumor associated DC subsets.
Subject(s)
Melanoma, Experimental , Ribonucleases , Mice , Animals , Ribonucleases/metabolism , Endoribonucleases/genetics , Endoribonucleases/metabolism , Adaptive Immunity , Ribonuclease, Pancreatic/metabolism , Melanoma, Experimental/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Dendritic CellsABSTRACT
INTRODUCTION: A therapeutic approach to severe obesity is bariatric surgery (BS), which is considered an effective intervention for ameliorating comorbidities such as T2DM, hypertension, dyslipidemia, and cardiovascular diseases. Some polymorphisms are considered markers for addictive disorders and hedonic hunger. We analyzed factors associated with the outcomes of BS, including rs1800497 ANKK1 and rs1799732 DRD2 polymorphisms, eating behavior, hedonic hunger, and depressive symptoms. METHODS: We retrospectively selected 101 patients who underwent BS and agreed to participate. The previous conditions to BS, such as body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), and comorbidities, were registered; the scholarship value was evaluated as the total number of years of scholarly education. To evaluate the post-surgery conditions of the participants, we took blood samples, anthropometric measures, and 3 questionnaires to evaluate eating behavior (TFEQ-R18), hedonic hunger (PFS), and depressive symptoms (PHQ-9). The ANKK1 rs1800497 and rs1799732 DRD2 polymorphisms were genotyped. RESULTS: The median total weight loss (TWL) was 34.7 kg, with a BMI of 33.8 kg/m2, 6 (4-8) years after BS. The TWL was positively associated with the TFEQ-R18 score (p = 0.006) and negatively associated with triglycerides (p = 0.011). rs1800497 ANKK1 was associated with TFEQ-R18 (OR = 1.13 (1.02-1.25), p = 0.009). We also found a negative correlation of pre-surgery BMI with scholarship (r = - 0.27, p < 0.05). CONCLUSION: The patients showed an improvement in metabolic and anthropometric parameters post-surgery. Interestingly, the ANKK1 Taq1A polymorphism was associated with eating behavior and scholarship with pre-surgery BMI, which may be considered predictors of BS outcomes.
Subject(s)
Bariatric Surgery , Depression , Humans , Depression/genetics , Hunger , Retrospective Studies , Receptors, Dopamine D2/genetics , Polymorphism, Genetic , Feeding Behavior , Protein Serine-Threonine Kinases/geneticsABSTRACT
Cancer is a leading cause of death worldwide, reporting nearly 10 million deaths in 2020. One of the hallmarks of cancer cells is their capability to evade growth suppressors and sustain proliferative signaling resulting in uncontrolled growth. The AMPK pathway, a catabolic via to economize ATP, has been associated with cancer. AMPK activation is related to cancer progression in advanced stages, while its activation by metformin or phenformin is associated with cancer chemoprevention. Thus, the role of the AMPK pathway in cancer growth modulation is not clear. Saccharomyces cerevisiae might be a useful model to elucidate AMPK participation in growth regulation since it shares a highly conserved AMPK pathway. Therefore, this work is aimed at evaluating the role of the AMPK pathway on S. cerevisiae growth under different nutritional conditions. Herein, we provide evidence that the SNF1 gene is necessary to maintain S. cerevisiae growth with glucose as a sole carbon source at every concentration tested. Resveratrol supplementation inhibited the exponential growth of snf1∆ strain at low glucose levels and decreased it at high glucose levels. SNF1 gene deletion impaired exponential growth in a carbohydrate concentration-dependent manner independently of nitrogen source or concentration. Interestingly, deletion of genes encoding for upstream kinases (SAK1, ELM1, and TOS3) also had a glucose dose-dependent effect upon exponential growth. Furthermore, gene deletion of regulatory subunits of the AMPK complex impacted exponential growth in a glucose-dependent manner. Altogether, these results suggest that the SNF1 pathway affects the exponential growth of S. cerevisiae in a glucose-dependent manner.
Subject(s)
Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolism , Protein Serine-Threonine Kinases/genetics , AMP-Activated Protein Kinases/genetics , AMP-Activated Protein Kinases/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Carbon/metabolism , Nitrogen/metabolism , Signal Transduction/physiology , Glucose/metabolism , Protein Kinases/geneticsABSTRACT
The U2AF Homology Motif Kinase 1 (UHMK1) is the only kinase that contains the U2AF homology motif, a common protein interaction domain among splicing factors. Through this motif, UHMK1 interacts with the splicing factors SF1 and SF3B1, known to participate in the 3' splice site recognition during the early steps of spliceosome assembly. Although UHMK1 phosphorylates these splicing factors in vitro, the involvement of UHMK1 in RNA processing has not previously been demonstrated. Here, we identify novel putative substrates of this kinase and evaluate UHMK1 contribution to overall gene expression and splicing, by integrating global phosphoproteomics, RNA-seq, and bioinformatics approaches. Upon UHMK1 modulation, 163 unique phosphosites were differentially phosphorylated in 117 proteins, of which 106 are novel potential substrates of this kinase. Gene Ontology analysis showed enrichment of terms previously associated with UHMK1 function, such as mRNA splicing, cell cycle, cell division, and microtubule organization. The majority of the annotated RNA-related proteins are components of the spliceosome but are also involved in several steps of gene expression. Comprehensive analysis of splicing showed that UHMK1 affected over 270 alternative splicing events. Moreover, splicing reporter assay further supported UHMK1 function on splicing. Overall, RNA-seq data demonstrated that UHMK1 knockdown had a minor impact on transcript expression and pointed to UHMK1 function in epithelial-mesenchymal transition. Functional assays demonstrated that UHMK1 modulation affects proliferation, colony formation, and migration. Taken together, our data implicate UHMK1 as a splicing regulatory kinase, connecting protein regulation through phosphorylation and gene expression in key cellular processes.
Subject(s)
Protein Serine-Threonine Kinases , RNA Splicing , Alternative Splicing , RNA Splicing Factors/metabolism , Spliceosomes/genetics , Spliceosomes/metabolism , Splicing Factor U2AF/chemistry , Transcription Factors/metabolism , Epithelial-Mesenchymal Transition , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolismABSTRACT
Mitochondrial dysfunction plays a central role in Parkinson's disease (PD) and can be triggered by xenobiotics and mutations in mitochondrial quality control genes, such as the PINK1 gene. Caffeine has been proposed as a secondary treatment to relieve PD symptoms mainly by its antagonistic effects on adenosine receptors (ARs). Nonetheless, the potential protective effects of caffeine on mitochondrial dysfunction could be a strategy in PD treatment but need further investigation. In this study, we used high-resolution respirometry (HRR) to test caffeine's effects on mitochondrial dysfunction in PINK1B9-null mutants of Drosophila melanogaster. PINK1 loss-of-function induced mitochondrial dysfunction in PINK1B9-null flies observed by a decrease in O2 flux related to oxidative phosphorylation (OXPHOS) and electron transfer system (ETS), respiratory control ratio (RCR) and ATP synthesis compared to control flies. Caffeine treatment improved OXPHOS and ETS in PINKB9-null mutant flies, increasing the mitochondrial O2 flux compared to untreated PINKB9-null mutant flies. Moreover, caffeine treatment increased O2 flux coupled to ATP synthesis and mitochondrial respiratory control ratio (RCR) in PINK 1B9-null mutant flies. The effects of caffeine on respiratory parameters were abolished by rotenone co-treatment, suggesting that caffeine exerts its beneficial effects mainly by stimulating the mitochondrial complex I (CI). In conclusion, we demonstrate that caffeine may improve mitochondrial function by increasing mitochondrial OXPHOS and ETS respiration in the PD model using PINK1 loss-of-function mutant flies.
Subject(s)
Drosophila Proteins , Drosophila melanogaster , Animals , Drosophila melanogaster/genetics , Drosophila Proteins/genetics , Drosophila Proteins/pharmacology , Caffeine/pharmacology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/pharmacology , Mitochondria , Adenosine Triphosphate/pharmacologyABSTRACT
Plant responses to phosphate starvation (-Pi) are very well characterized at the biochemical and molecular levels. The expression of thousands of genes is modified under this stress condition, depending on the action of Phosphate starvation response 1 (PHR1). Existing data indicate that neither the PHR1 transcript nor the quantity or localization of its protein increase during nutrient stress, raising the question of how its activity is regulated. Here, we present data showing that SnRK1 kinase is able to phosphorylate some phosphate starvation response proteins (PSRs), including PHR1. Based on a model of the three-dimensional structure of the catalytic subunit SnRK1α1, docking simulations predicted the binding modes of peptides from PHT1;8, PHO1 and PHR1 with SnRK1. PHR1 recombinant protein interacted in vitro with the catalytic subunits SnRK1α1 and SnRK1α2. A BiFC assay corroborated the in vivo interaction between PHR1 and SnRK1α1 in the cytoplasm and nucleus. Analysis of phosphorylated residues suggested the presence of one phosphorylated site containing the SnRK1 motif at S11, and mutation in this residue disrupted the incorporation of 32 P, suggesting that it is a major phosphorylation site. Electrophoretic mobility shift assay results indicated that the binding of PHR1 to P1BS motifs was not influenced by phosphorylation. Importantly, transient expression assays in Arabidopsis protoplasts showed a decrease in PHR1 activity in contrast with the S11A mutant, suggesting a role for Ser11 as a negative regulatory phosphorylation site. Taken together, these findings suggest that phosphorylation of PHR1 at Ser11 is a mechanism to control the PHR1-mediated adaptive response to -Pi.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Transcription Factors/metabolism , Phosphorylation , Arabidopsis/metabolism , Phosphates , Gene Expression Regulation, Plant , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolismABSTRACT
Sucrose non-fermentation-related protein kinase 1 (SnRK1) a Ser/Thr protein kinase, is known to play a crucial role in plants during biotic and abiotic stress responses by activating protein phosphorylation pathways. SnRK1 and some members of the plant-specific SnRK2 and SnRK3 sub-families have been studied in different plant species. However, a comprehensive study of the SnRK gene family in Phaseolus vulgaris is not available. Symbiotic associations of P. vulgaris with Rhizobium and/or mycorrhizae are crucial for the growth and productivity of the crop. In the present study, we identified PvSnRK genes and analysed their expression in response to the presence of the symbiont. A total of 42 PvSnRK genes were identified in P. vulgaris and annotated by comparing their sequence homology to Arabidopsis SnRK genes. Phylogenetic analysis classified the three sub-families into individual clades, and PvSnRK3 was subdivided into two groups. Chromosome localization analysis showed an uneven distribution of PvSnRK genes on 10 of the 11 chromosomes. Gene structural analysis revealed great variation in intron number in the PvSnRK3 sub-family, and motif composition is specific and highly conserved in each sub-family of PvSnRKs. Analysis of cis-acting elements suggested that PvSnRK genes respond to hormones, symbiosis and other abiotic stresses. Furthermore, expression data from databases and transcriptomic analyses revealed differential expression patterns for PvSnRK genes under symbiotic conditions. Finally, an in situ gene interaction network of the PvSnRK gene family with symbiosis-related genes showed direct and indirect interactions. Taken together, the present study contributes fundamental information for a better understanding of the role of the PvSnRK gene family not only in symbiosis but also in other biotic and abiotic interactions in P. vulgaris.
Subject(s)
Mycorrhizae , Phaseolus , Protein Serine-Threonine Kinases , Rhizobium , Mycorrhizae/physiology , Phaseolus/genetics , Phaseolus/microbiology , Phylogeny , Protein Serine-Threonine Kinases/genetics , Rhizobium/physiology , Symbiosis/geneticsABSTRACT
Aging is a major risk factor to develop neurodegenerative diseases and is associated with decreased buffering capacity of the proteostasis network. We investigated the significance of the unfolded protein response (UPR), a major signaling pathway activated to cope with endoplasmic reticulum (ER) stress, in the functional deterioration of the mammalian brain during aging. We report that genetic disruption of the ER stress sensor IRE1 accelerated age-related cognitive decline. In mouse models, overexpressing an active form of the UPR transcription factor XBP1 restored synaptic and cognitive function, in addition to reducing cell senescence. Proteomic profiling of hippocampal tissue showed that XBP1 expression significantly restore changes associated with aging, including factors involved in synaptic function and pathways linked to neurodegenerative diseases. The genes modified by XBP1 in the aged hippocampus where also altered. Collectively, our results demonstrate that strategies to manipulate the UPR in mammals may help sustain healthy brain aging.
Subject(s)
Aging , Brain , Protein Serine-Threonine Kinases , Unfolded Protein Response , X-Box Binding Protein 1 , Animals , Mice , Aging/genetics , Brain/metabolism , Endoplasmic Reticulum Stress/genetics , Protein Serine-Threonine Kinases/genetics , Proteomics , Signal Transduction/physiology , X-Box Binding Protein 1/genetics , X-Box Binding Protein 1/metabolismABSTRACT
The study aimed to explore the influence of genetic polymorphisms in ANKK1 and DRD2 on the signs and symptoms of temporomandibular disorder (TMD) in construction workers. This cross-sectional study included only male subjects. All construction workers were healthy and over 18 years age. Illiterate workers and functionally illiterate workers were excluded. The diagnosis of TMD was established according to the Research Diagnostic Criteria for TMD (RDC/TMD). Genomic DNA was used to evaluate the genetic polymorphisms ANKK1 (rs1800497) and DRD2 (rs6275; rs6276) using Real-Time PCR. Chi-square or Fisher exact tests were used to evaluate genotypes and allele distribution among the studied phenotypes. The established alpha of this study was 5%. The sample included a total of 115 patients. The age of the patients ranged from 19 to 70 years (mean age 38.2; standard deviation 11.7). Chronic pain (87.7%), disc displacement (38.2%), and joint inflammation (26.9%) were the most frequently observed signs and symptoms. The genetic polymorphism rs6276 in DRD2 was associated with chronic pain (p=0.033). In conclusion, our study suggests that genetic polymorphisms in DRD2 and ANKK1 may influence TMD signs and symptoms in a group of male construction workers.
Subject(s)
Chronic Pain , Construction Industry , Protein Serine-Threonine Kinases , Receptors, Dopamine D2 , Temporomandibular Joint Disorders , Chronic Pain/genetics , Cross-Sectional Studies , Genotype , Humans , Male , Protein Serine-Threonine Kinases/genetics , Receptors, Dopamine D2/genetics , Temporomandibular Joint Disorders/geneticsABSTRACT
BACKGROUND: Mutations in STK11 (STK11Mut) and, frequently co-occurring, KEAP1 mutations (KEAP1Mut) are associated with poor survival in metastatic Non-small Cell Lung Cancer (mNSCLC) patients treated with immunotherapy. However, there are limited data regarding the prognostic or predictive significance of these genomic alterations among Hispanics. METHODS: This retrospective study analyzed a cohort of Hispanic patients (N = 103) diagnosed with mNSCLC from the US and seven Latin American countries (LATAM) treated with immune checkpoint inhibitors (ICI) alone or in combination as first-line (Cohort A). All cases were treated in routine care between January 2016 and December 2021. The main objectives were to determine the association of mutations in STK11 or KEAP1 in these patients' tumors with overall (OS) and progression-free survival (PFS), presence of KRAS mutations, tumor mutational burden (TMB), and other relevant clinical variables. To compare outcomes with a STK11Wt/KEAP1Wt population, historical data from a cohort of Hispanic patients (N = 101) treated with first-line ICI was used, matching both groups by country of origin, gender, and Programed Death-ligand 1 (PD-L1) expression level (Cohort B). RESULTS: Most tumors had mutations only in STK11 or KEAP1 (45.6%) without KRAS co-mutation or any other genomic alteration. Besides, 35%, 8.7%, 6.8%, and 3.9% were KRASMut + STK11Mut, KRASMut + STK11Mut + KEAP1Mut, STK11Mut + KEAP1Mut, and KRASMut + KEAP1Mut, respectively. Based on KRAS status, STK11 alterations were associated with significantly lower PD-L1 expression among those with KRASWt (p = 0.023), whereas KEAP1 mutations were predominantly associated with lower PD-L1 expression among KRASMut cases (p = 0.047). Tumors with KRASMut + KEAP1Mut had significantly higher median TMB when compared to other tumors (p = 0.040). For Cohort A, median PFS was 4.9 months (95%CI 4.3-5.4), slightly longer in those with KEAP1mut 6.1 months versus STK11Mut 4.7 months (p = 0.38). In the same cohort, PD-L1 expression and TMB did not influence PFS. OS was significantly longer among patients with tumors with PD-L1 ≥ 50% (30.9 months), and different from those with PD-L1 1-49% (22.0 months), and PD-L1 < 1% (12.0 months) (p = 0.0001). When we compared the cohorts A and B, OS was significantly shorter for patients carrying STK1 [STK11Mut 14.2 months versus STK11Wt 27.0 months (p = 0.0001)] or KEAP1 [KEAP1Mut 12.0 months versus KEAP1Wt 24.4 months (p = 0.005)] mutations. PD-L1 expression significantly affected OS independently of the presence of mutations in STK11, KEAP1, or KRAS. TMB-H favored better OS. CONCLUSIONS: This is the first large Hispanic cohort to study the impact of STK11 and KEAP1 mutations in NSCLC patient treated with ICI. Our data suggest that mutations in the above-mentioned genes are associated with PD-L1 expression levels and poor OS.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , AMP-Activated Protein Kinase Kinases , B7-H1 Antigen/genetics , Biomarkers, Tumor/genetics , Carcinoma, Non-Small-Cell Lung/drug therapy , Hispanic or Latino/genetics , Humans , Kelch-Like ECH-Associated Protein 1/genetics , Lung Neoplasms/pathology , Mutation , NF-E2-Related Factor 2/genetics , Prognosis , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Registries , Retrospective StudiesABSTRACT
Reactive oxygen species (ROS) are constantly produced in cells, an excess of which causes oxidative stress. ROS has been linked to regulation of the Hippo pathway; however, the underlying detailed mechanisms remain unclear. Here, we report that MOB1, a substrate of MST1/2 and co-activator of LATS1/2 in the canonical Hippo pathway, interacts with and is acetylated at lysine 11 by acetyltransferase CBP and deacetylated by HDAC6. MOB1-K11 acetylation stabilizes itself by reducing its binding capacity with E3 ligase Praja2 and subsequent ubiquitination. MOB1-K11 acetylation increases its phosphorylation and activates LATS1. Importantly, upstream oxidative stress signals promote MOB1 acetylation by suppressing CBP degradation, independent of MST1/2 kinase activity and HDAC6 deacetylation effect, thereby linking oxidative stress to activation of the Hippo pathway. Functionally, the acetylation-deficient mutant MOB1-K11R promotes lung cancer cell proliferation, migration and invasion in vitro and accelerates tumor growth in vivo, compared to the wild-type MOB1. Clinically, acetylated MOB1 corresponds to better prediction of overall survival in patients with non-small cell lung cancer. Therefore, as demonstrated, an oxidative stress-CBP regulatory axis controls MOB1-K11 acetylation and activates LATS1, thereby activating the Hippo pathway and suppressing YAP/TAZ nuclear translocation and tumor progression.