55 research outputs found
Calpain-mediated proteolysis of polycystin-1 C-terminus induces JAK2 and ERK signal alterations
AbstractAutosomal dominant polycystic kidney disease (ADPKD), a hereditary renal disease caused by mutations in PKD1 (85%) or PKD2 (15%), is characterized by the development of gradually enlarging multiple renal cysts and progressive renal failure. Polycystin-1 (PC1), PKD1 gene product, is an integral membrane glycoprotein which regulates a number of different biological processes including cell proliferation, apoptosis, cell polarity, and tubulogenesis. PC1 is a target of various proteolytic cleavages and proteosomal degradations, but its role in intracellular signaling pathways remains poorly understood. Herein, we demonstrated that PC1 is a novel substrate for Ό- and m-calpains, which are calcium-dependent cysteine proteases. Overexpression of PC1 altered both Janus-activated kinase 2 (JAK2) and extracellular signal-regulated kinase (ERK) signals, which were independently regulated by calpain-mediated PC1 degradation. They suggest that the PC1 function on JAK2 and ERK signaling pathways might be regulated by calpains in response to the changes in intracellular calcium concentration
A Survey of Diabetic Educators and Patients for the Revision of Korean Food Exchange Lists
BackgroundFood exchange lists are one of the main methods of nutritional education. However, Korean food exchange lists have not been revised since 1994. Therefore, we surveyed the opinions of diabetes educators and patients with diabetes regarding the need for revision of the current food exchange lists.MethodsFor two weeks beginning on 10 March 2008, a 12-item questionnaire regarding the opinion and need for revision of the current food exchange lists was e-mailed to diabetes educators nationwide. Another 15-question survey was administered to patients with diabetes in 13 hospitals located in the Seoul and Gyeonggi regions of Korea.ResultsWe obtained survey responses from 101 diabetes educators and 209 patients; 65 (64.3%) of the educators answered that the current food exchange lists should be revised. The items that needed revision were the glycemic index, addition of new foods and reaffirmation of exchange standard amounts. The patients demanded specific education about choosing appropriate foods, a balanced meal plan, proper snacks, and dining intake.ConclusionOur survey results demonstrate the need to revise the Korean food exchange lists. This process should focus on glycemic index, the addition of new foods and reconfirmation of one exchange reference unit
Stability and inheritance of endosperm-specific expression of two transgenes in progeny from crossing independently transformed barley plants
To study stability and inheritance of two different transgenes in barley, we crossed a homozygous T8 plant, having uidA (or gus) driven by the barley endosperm-specific B1-hordein promoter (localized in the near centromeric region of chromosome 7H) with a second homozygous T4 plant, having sgfp(S65T) driven by the barley endosperm-specific D-hordein promoter (localized on the subtelomeric region of chromosome 2H). Both lines stably expressed the two transgenes in the generations prior to the cross. Three independently crossed F1 progeny were analyzed by PCR for both uidA and sgfp(S65T) in each plant and functional expression of GUS and GFP in F2 seeds followed a 3:1 Mendelian segregation ratio and transgenes were localized by FISH to the same location as in the parental plants. FISH was used to screen F2 plants for homozygosity of both transgenes; four homozygous plants were identified from the two crossed lines tested. FISH results showing presence of transgenes were consistent with segregation ratios of expression of both transgenes, indicating that the two transgenes were expressed without transgene silencing in homozygous progeny advanced to the F3 and F4 generations. Thus, even after crossing independently transformed, homozygous parental plants containing a single, stably expressed transgene, progeny were obtained that continued to express multiple transgenes through generation advance. Such stability of transgenes, following outcrossing, is an important attribute for trait modification and for gene flow studies
Pentraxin 3 deficiency enhances features of chronic rejection in a mouse orthotopic lung transplantation model
Chronic lung allograft dysfunction (CLAD) is a serious complication after lung transplantation and thought to represent chronic rejection. Increased expression of Pentraxin 3 (PTX3), an acute phase protein, was associated with worse outcome in lung transplant patients. To determine the role of recipient PTX3 in development of chronic rejection, we used a minor alloantigen-mismatched murine orthotopic single lung transplant model. Male C57BL/10 mice were used as donors. Male PTX3 knockout (KO) mice and their wild type (WT) littermates on 129/SvEv/C57BL6/J background were used as recipients. In KO recipients, 7/13 grafted lungs were consolidated without volume recovery on CT scan, while only 2/9 WT mice showed similar graft consolidation. For grafts where lung volume could be reliably analyzed by CT scan, the lung volume recovery was significantly reduced in KO mice compared to WT. Interstitial inflammation, parenchymal fibrosis and bronchiolitis obliterans scores were significantly higher in KO mice. Presence of myofibroblasts and lymphoid aggregation was significantly enhanced in the grafts of PTX3 KO recipients. Recipient PTX3 deficiency enhanced chronic rejection-like lesions by promoting a fibrotic process in the airways and lung parenchyma. The underlying mechanisms and potential protective role of exogenous PTX3 as a therapy should be further explored
Gene Expression Pattern in Transmitochondrial Cytoplasmic Hybrid Cells Harboring Type 2 Diabetes-Associated Mitochondrial DNA Haplogroups
Decreased mitochondrial function plays a pivotal role in the pathogenesis of type 2 diabetes mellitus (T2DM). Recently, it was reported that mitochondrial DNA (mtDNA) haplogroups confer genetic susceptibility to T2DM in Koreans and Japanese. Particularly, mtDNA haplogroup N9a is associated with a decreased risk of T2DM, whereas haplogroups D5 and F are associated with an increased risk. To examine functional consequences of these haplogroups without being confounded by the heterogeneous nuclear genomic backgrounds of different subjects, we constructed transmitochondrial cytoplasmic hybrid (cybrid) cells harboring each of the three haplogroups (N9a, D5, and F) in a background of a shared nuclear genome. We compared the functional consequences of the three haplogroups using cell-based assays and gene expression microarrays. Cell-based assays did not detect differences in mitochondrial functions among the haplogroups in terms of ATP generation, reactive oxygen species production, mitochondrial membrane potential, and cellular dehydrogenase activity. However, differential expression and clustering analyses of microarray data revealed that the three haplogroups exhibit a distinctive nuclear gene expression pattern that correlates with their susceptibility to T2DM. Pathway analysis of microarray data identified several differentially regulated metabolic pathways. Notably, compared to the T2DM-resistant haplogroup N9a, the T2DM-susceptible haplogroup F showed down-regulation of oxidative phosphorylation and up-regulation of glycolysis. These results suggest that variations in mtDNA can affect the expression of nuclear genes regulating mitochondrial functions or cellular energetics. Given that impaired mitochondrial function caused by T2DM-associated mtDNA haplogroups is compensated by the nuclear genome, we speculate that defective nuclear compensation, under certain circumstances, might lead to the development of T2DM
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Search for light Higgs bosons from supersymmetric cascade decays in pp collisions at âs=13TeV
A search is reported for pairs of light Higgs
bosons (H1) produced in supersymmetric cascade decays in
f
inal states with small missing transverse momentum. A data
set of LHC pp collisions collected with the CMS detector
at âs = 13TeV and corresponding to an integrated lumi
nosity of 138fbâ1 is used. The search targets events where
both H1 bosons decay into bÂŻb pairs that are reconstructed
as large-radius jets using substructure techniques. No evi
dence is found for an excess of events beyond the back
ground expectations of the standard model (SM). Results
from the search are interpreted in the next-to-minimal super
symmetric extension of the SM, where a âsinglinoâ of small
mass leads to squark and gluino cascade decays that can pre
dominantly end in a highly Lorentz-boosted singlet-like H1
andasinglino-likeneutralinoofsmalltransversemomentum.
Upperlimitsaresetontheproductofthesquarkorgluinopair
production cross section and the square of the bÂŻb branching
fraction of the H1 in a benchmark model containing almost
mass-degenerategluinosandlight-flavoursquarks.Underthe
assumption of an SM-like H1 â bÂŻb branching fraction, H1
bosonswithmassesintherange40â120GeVarisingfromthe
decays of squarks or gluinos with a mass of 1200â2500GeV
are excluded at 95% confidence level.SCOA
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Measurements of Higgs boson production in the decay channel with a pair of leptons in proton-proton collisions at = 13 TeV
A preprint version of the article is available at arXiv:2204.12957v2 [hep-ex], https://arxiv.org/abs/2204.12957v2 . Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables, including additional supplementary figures and tables, can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-19-010 (CMS Public Pages). Report number: CMS-HIG-19-010, CERN-EP-2022-027.Measurements of Higgs boson production, where the Higgs boson decays into a pair of Ï leptons, are presented, using a sample of proton-proton collisions collected with the CMS experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb^{â1}. Three analyses are presented. Two are targeting Higgs boson production via gluon fusion and vector boson fusion: a neural network based analysis and an analysis based on an event categorization optimized on the ratio of signal over background events. These are complemented by an analysis targeting vector boson associated Higgs boson production. Results are presented in the form of signal strengths relative to the standard model predictions and products of cross sections and branching fraction to Ï leptons, in up to 16 different kinematic regions. For the simultaneous measurements of the neural network based analysis and the analysis targeting vector boson associated Higgs boson production signal strengths are found to be 0.82 ± 0.11 for inclusive Higgs boson production, 0.67 ± 0.19 (0.81 ± 0.17) for the production mainly via gluon fusion (vector boson fusion), and 1.79 ± 0.45 for vector boson associated Higgs boson production.SCOAP3
Understanding the Role of an Adaptor Protein, XB130, in Tumorigenesis
Adaptor proteins are essential proteins involved in the regulation of signal transduction pathways. XB130 is one type of adaptor proteins, which functions as an intracellular mediator for regulating cellular activities, such as cell proliferation, cell survival, cell migration, invasion, and cytoskeleton regulation, in various normal and cancer cells. Currently, the exact physiological roles of XB130 in in vivo tumorigenesis remain unknown. To investigate its functions, two studies were performed using XB130-deleted mice: (1) a two-stage dimethylbenzanthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin tumorigenesis study, and (2) a study on spontaneous tumorigenesis of aged mice.
First, through the carcinogen-induced tumorigenesis approach, XB130 is identified as a putative tumor suppressor and regulator of inflammatory response. The multiplicity and size of DMBA (mutagen)/TPA (tumor promoter)-induced epidermal tumors in XB130 knockout (XB130-/-) males were significantly increased compared with those of wild-type (XB130+/+) littermate males. In the absence of XB130, keratinocyte proliferation, edema formation, neutrophil infiltration, expression of pro-inflammatory cytokines, as well as inflammation- and cell proliferation-related signaling pathways were altered dramatically in response to repeated TPA stimuli in males. These changes may have orchestrated tumor microenvironment favoring the skin tumorigenesis in XB130-/- mice.
In the second study, aged XB130-/- mice had increased spontaneous occurrence of benign enlarged thyroid glands with various nodules, which were diagnosed as multinodular goiters. XB130-/- thyroid glands exhibited architectural distortion with higher proliferation of follicular cells in nodules, as well as disrupted expression and distribution of cytoskeleton elements and junction proteins. XB130-/- mice were hypothyroid, displaying defective organification of iodide during perchlorate discharge test and reduced expression of iodinated thyroglobulin. XB130 was confirmed to be localized at the apical side of thyroid follicles at which thyroglobulin iodination normally occurs. As compensatory mechanism to the loss of XB130, thyroperoxidase (TPO) activity was enhanced in aged XB130-/- thyroid glands, with increased affinity of TPO for iodide and higher expression of TPO protein. Thus, XB130 deficiency led to the pathogenesis of benign multinodular goiters as the manifestation of dyshormonogenic hypothyroidism.
In summary, this work highlighted the tumor-suppressive role of XB130 in carcinogen-induced tumorigenesis study and introduced its novel involvement in thyroid function through spontaneous tumorigenesis study.Ph.D.2021-11-30 00:00:0
XB130âA Novel Adaptor Protein: Gene, Function, and Roles in Tumorigenesis
Several adaptor proteins have previously been shown to play an important role in the promotion of tumourigenesis. XB130 (AFAP1L2) is an adaptor protein involved in many cellular functions, such as cell survival, cell proliferation, migration, and gene and miRNA expression. XB130âs functional domains and motifs enable its interaction with a multitude of proteins involved in several different signaling pathways. As a tyrosine kinase substrate, tyrosine phosphorylated XB130 associates with the p85α regulatory subunit of phosphoinositol-3-kinase (PI3K) and subsequently affects Akt activity and its downstream signalling. Tumourigenesis studies show that downregulation of XB130 expression by RNAi inhibits tumor growth in mouse xenograft models. Furthermore, XB130 affects tumor oncogenicity by regulating the expression of specific tumour suppressing miRNAs. The expression level and pattern of XB130 has been studied in various human tumors, such as thyroid, esophageal, and gastric cancers, as well as, soft tissue tumors. Studies show the significant effects of XB130 in tumourigenesis and suggest its potential as a diagnostic biomarker and therapeutic target for cancer treatments.Peer Reviewe
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