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1.
Biomedicines ; 12(6)2024 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-38927549

RÉSUMÉ

Gastrointestinal cancers, which include a variety of esophageal and colorectal malignancies, present a global health challenge and require effective treatment strategies. In the evolving field of cancer immunotherapy, tissue-resident memory T cells (Trm cells) have emerged as important players in the immune response within nonlymphoid tissues. In this review, we summarize the characteristics and functions of Trm cells and discuss their profound implications for patient outcomes in gastrointestinal cancers. Positioned strategically in peripheral tissues, Trm cells have functions beyond immune surveillance, affecting tumor progression, prognosis, and response to immunotherapy. Studies indicate that Trm cells are prognostic markers and correlate positively with enhanced survival. Their presence in the tumor microenvironment has sparked interest in their therapeutic potential, particularly with respect to immune checkpoint inhibitors, which may improve cancer treatment. Understanding how Trm cells work will not only help to prevent cancer spread through effective treatment but will also contribute to disease prevention at early stages as well as vaccine development. The role of Trm cells goes beyond just cancer, and they have potential applications in infectious and autoimmune diseases. This review provides a thorough analysis of Trm cells in gastrointestinal cancers, which may lead to personalized and effective cancer therapies.

2.
Front Mol Biosci ; 11: 1191246, 2024.
Article de Anglais | MEDLINE | ID: mdl-38516186

RÉSUMÉ

NSD3 is a member of six H3K36-specific histone lysine methyltransferases in metazoans. Its overexpression or mutation is implicated in developmental defects and oncogenesis. Aside from the well-characterized catalytic SET domain, NSD3 has multiple clinically relevant potential chromatin-binding motifs, such as the proline-tryptophan-tryptophan-proline (PWWP), the plant homeodomain (PHD), and the adjacent Cys-His-rich domain located at the C-terminus. The crystal structure of the individual domains is available, and this structural knowledge has allowed the designing of potential inhibitors, but the intrinsic flexibility of larger constructs has hindered the characterization of mutual domain conformations. Here, we report the first structural characterization of the NSD3 C-terminal region comprising the PWWP2, SET, and PHD4 domains, which has been achieved at a low resolution in solution by small-angle X-ray scattering (SAXS) data on two multiple-domain NSD3 constructs complemented with size-exclusion chromatography and advanced computational modeling. Structural models predicted by machine learning have been validated in direct space, by comparison with the SAXS-derived molecular envelope, and in reciprocal space, by reproducing the experimental SAXS profile. Selected models have been refined by SAXS-restrained molecular dynamics. This study shows how SAXS data can be used with advanced computational modeling techniques to achieve a detailed structural characterization and sheds light on how NSD3 domains are interconnected in the C-terminus.

3.
Biomedicines ; 11(11)2023 Oct 26.
Article de Anglais | MEDLINE | ID: mdl-38001906

RÉSUMÉ

Early cancer detection is key to improving patient survival and quality of life and reducing cancer treatments' financial burden [...].

4.
Biomedicines ; 11(9)2023 Sep 18.
Article de Anglais | MEDLINE | ID: mdl-37760999

RÉSUMÉ

The pancreas is a vital organ with exocrine and endocrine functions. Pancreatitis is an inflammation of the pancreas caused by alcohol consumption and gallstones. This condition can heighten the risk of pancreatic cancer (PC), a challenging disease with a high mortality rate. Genetic and epigenetic factors contribute significantly to PC development, along with other risk factors. Early detection is crucial for improving PC outcomes. Diagnostic methods, including imagining modalities and tissue biopsy, aid in the detection and analysis of PC. In contrast, liquid biopsy (LB) shows promise in early tumor detection by assessing biomarkers in bodily fluids. Understanding the function of the pancreas, associated diseases, risk factors, and available diagnostic methods is essential for effective management and early PC detection. The current clinical examination of PC is challenging due to its asymptomatic early stages and limitations of highly precise diagnostics. Screening is recommended for high-risk populations and individuals with potential benign tumors. Among various PC screening methods, the N-NOSE plus pancreas test stands out with its high AUC of 0.865. Compared to other commercial products, the N-NOSE plus pancreas test offers a cost-effective solution for early detection. However, additional diagnostic tests are required for confirmation. Further research, validation, and the development of non-invasive screening methods and standardized scoring systems are crucial to enhance PC detection and improve patient outcomes. This review outlines the context of pancreatic cancer and the challenges for early detection.

5.
Biomedicines ; 10(10)2022 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-36289633

RÉSUMÉ

Regular cancer screening is critical for early cancer detection. Cancer screening tends to be burdensome, invasive, and expensive, especially for a comprehensive multi-organ check. Improving the rate and effectiveness of routine cancer screenings remain a challenge in health care. Multi-cancer early detection (MCED) is an exciting concept and a potentially effective solution for addressing current issues with routine cancer screening. In recent years, several technologies have matured for MCED, such as identifying cell-free tumor DNA in blood or using organisms such as Caenorhabditis elegans as a tool for early cancer detection. In Japan, N-NOSE is a commercially available multi-cancer detection test based on the chemotaxis of C. elegans using a urine sample showing 87.5% sensitivity and 90.2% specificity. In this review, we focus on using C. elegans as a powerful biosensor for universal cancer screening. We review N-NOSE clinical research results, spotlighting it as an effective primary cancer screening test.

6.
Biomolecules ; 12(10)2022 Oct 17.
Article de Anglais | MEDLINE | ID: mdl-36291712

RÉSUMÉ

Pancreatic ductal adenocarcinoma (PDAC) is caused by genetic mutations in four genes: KRAS proto-oncogene and GTPase (KRAS), tumor protein P53 (TP53), cyclin-dependent kinase inhibitor 2A (CDKN2A), and mothers against decapentaplegic homolog 4 (SMAD4), also called the big 4. The changes in tumors are very complex, making their characterization in the early stages challenging. Therefore, the development of innovative therapeutic approaches is desirable. The key to overcoming PDAC is diagnosing it in the early stages. Therefore, recent studies have investigated the multifaced characteristics of PDAC, which includes cancer cell metabolism, mesenchymal cells including cancer-associated fibroblasts and immune cells, and metagenomics, which extend to characterize various biomolecules including RNAs and volatile organic compounds. Various alterations in the KRAS-dependent as well as KRAS-independent pathways are involved in the refractoriness of PDAC. The optimal combination of these new technologies is expected to help treat intractable pancreatic cancer.


Sujet(s)
Carcinome du canal pancréatique , Tumeurs du pancréas , Composés organiques volatils , Humains , Protéine p53 suppresseur de tumeur/métabolisme , Protéines proto-oncogènes p21(ras)/génétique , Protéines proto-oncogènes p21(ras)/métabolisme , Tumeurs du pancréas/métabolisme , Carcinome du canal pancréatique/métabolisme , Mutation , ADN/usage thérapeutique , Kinases cyclines-dépendantes/métabolisme , Tumeurs du pancréas
7.
Biochem Biophys Rep ; 32: 101332, 2022 Dec.
Article de Anglais | MEDLINE | ID: mdl-36111250

RÉSUMÉ

Cancer is the leading cause of death in dogs and cats. Early diagnosis of cancer is critical for effective treatment and improving survival rates. Nematode-NOSE (N-NOSE) is a commercially available non-invasive human cancer screening test that uses the sense of smell of the nematode Caenorhabditis elegans showing a distinct chemotactic response toward the urine of an individual with cancer compared to healthy ones. 15 types of human cancer (stomach, colon-rectum, lung, breast, pancreas, liver, prostate, uterus, esophagus, gallbladder, bile duct, kidney, urinary bladder, ovary, and oropharynx cancers) can be detected by N-NOSE. A non-invasive method for accurate cancer screening is needed for pets. In this study, we evaluated the effectiveness of N-NOSE in detecting cancer using canine and feline urine samples. We found a significant difference in chemotaxis index values between healthy subjects and cancer patients in both canine (p < 0.01*) and feline (p < 0.04*) urine samples. Receiver operating characteristic (ROC) analysis highlights the good performance of the test with areas under the curve (AUC) of 0.8114 and 0.7851 for dogs and 0.7667 and 0.9000 for cats when using 2 different dilutions of urine samples. Our study suggests that N-NOSE has the potential as a simple, accurate, and low-cost cancer screening test in both dogs and cats.

8.
Curr Issues Mol Biol ; 44(2): 988-997, 2022 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-35723350

RÉSUMÉ

Nematodes, such as Caenorhabditis elegans, have been instrumental to the study of cancer. Recently, their significance as powerful cancer biodiagnostic tools has emerged, but also for mechanism analysis and drug discovery. It is expected that nematode-applied technology will facilitate research and development on the human tumor microenvironment. In the history of cancer research, which has been spurred by numerous discoveries since the last century, nematodes have been important model organisms for the discovery of cancer microenvironment. First, microRNAs (miRNAs), which are noncoding small RNAs that exert various functions to control cell differentiation, were first discovered in C. elegans and have been actively incorporated into cancer research, especially in the study of cancer genome defects. Second, the excellent sense of smell of nematodes has been applied to the diagnosis of diseases, especially refractory tumors, such as human pancreatic cancer, by sensing complex volatile compounds derived from heterogeneous cancer microenvironment, which are difficult to analyze using ordinary analytical methods. Third, a nematode model system can help evaluate invadosomes, the phenomenon of cell invasion by direct observation, which has provided a new direction for cancer research by contributing to the elucidation of complex cell-cell communications. In this cutting-edge review, we highlight milestones in cancer research history and, from a unique viewpoint, focus on recent information on the contributions of nematodes in cancer research towards precision medicine in humans.

9.
Cancer Treat Res Commun ; 27: 100370, 2021.
Article de Anglais | MEDLINE | ID: mdl-33901923

RÉSUMÉ

Early cancer detection is critical for effective treatment. N-NOSE (Nematode-NOSE) is a simple, inexpensive, and highly sensitive cancer screening method based on the chemotaxis of the nematode Caenorhabditis elegans, which shows evasive action from the urine of healthy individuals while being attracted to the urine of cancer patients. Initially, N-NOSE relied on chemotaxis indexes obtained with 10-fold dilutions of urine samples. However, cancer tissue size and concentrations of cancer odors differ among cancer patients. In this study, we examined the accuracy improvement of N-NOSE method by using two types of dilutions, 10-fold and 100-fold. We have conducted N-NOSE tests with urine samples from 32 cancer patients (esophageal, gastric, colorectal, gallbladder, cholangiocarcinoma, breast, malignant lymphoma, and acute myeloid leukemia) along with 143 healthy subjects. Our data showed a significant difference in the N-NOSE at 10-fold dilution between the two groups (p < 0.0001), with an area under the ROC curve (AUC) of 0.9188 based on receiver operating characteristic (ROC) analysis. N-NOSE index at 100-fold dilutions was also significantly different between the two groups (p < 0.0001), with an AUC of 0.9032 based on ROC analysis. In this clinical study, we further improve N-NOSE with a combined method of two dilutions (10-fold and 100-fold) of urine samples, which results in a markedly improvement in cancer detection sensitivity of 87.5%. N-NOSE sensitivity improvement was significantly high even for early-stage cancer detection, which is in stark contrast with the sensitivity of detection using blood tumor markers (CEA, CA19-9 and CA15-3). These results strongly suggest that the N-NOSE test by this new combined method strikes a good balance between sensitivity and specificity.


Sujet(s)
Caenorhabditis elegans/physiologie , Chimiotaxie , Dépistage précoce du cancer/méthodes , Tumeurs/diagnostic , Tumeurs/urine , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Animaux , Aire sous la courbe , Antigène CA 19-9/sang , Antigène carcinoembryonnaire/sang , Études cas-témoins , Femelle , Humains , Mâle , Adulte d'âge moyen , Mucine-1/sang , Tumeurs/sang , Courbe ROC , Urine/composition chimique
10.
Front Mol Biosci ; 7: 577284, 2020.
Article de Anglais | MEDLINE | ID: mdl-33344501

RÉSUMÉ

7,3',4'-Trihydroxyisoflavone (7,3',4'-THIF) is a metabolite of daidzein which is a representative isoflavone found in soybean. Recent studies suggested that 7,3',4'-THIF exerts a hypopigmentary effect in B16F10 cells, however, its underlying molecular mechanisms and specific target protein remain unknown. Here, we found that 7,3',4'-THIF, but not daidzein, inhibited α-melanocyte-stimulating hormone (MSH)-induced intracellular and extracellular melanin production in B16F10 cells by directly targeting melanocortin 1 receptor (MC1R). Western blot data showed that 7,3',4'-THIF inhibited α-MSH-induced tyrosinase, tyrosinase-related protein-1 (TYRP-1), and tyrosinase-related protein-2 (TYRP-2) expressions through the inhibition of Microphthalmia-associated transcription factor (MITF) expression and cAMP response element-binding (CREB) phosphorylation. 7,3',4'-THIF also inhibited α-MSH-induced dephosphorylation of AKT and phosphorylation of p38 and cAMP-dependent protein kinase (PKA). cAMP and Pull-down assays indicated that 7,3',4'-THIF strongly inhibited forskolin-induced intracellular cAMP production and bound MC1R directly by competing with α-MSH. Moreover, 7,3',4'-THIF inhibited α-MSH-induced intracellular melanin production in human epidermal melanocytes (HEMs). Collectively, these results demonstrate that 7,3',4'-THIF targets MC1R, resulting in the suppression of melanin production, suggesting a protective role for 7,3',4'-THIF against melanogenesis.

11.
J Microbiol Biotechnol ; 30(2): 296-305, 2020 Feb 28.
Article de Anglais | MEDLINE | ID: mdl-32120462

RÉSUMÉ

Tricholoma matsutake is an ectomycorrhizal fungus, related with the host of Pinus densiflora. Most of studies on T. matsutake have focused on mycelial growth, genes and genomics, phylogenetics, symbiosis, and immune activity of this strain. T. matsutake is known for its unique fragrance in Eastern Asia. The most major component of its scent is (R)-(-)-1-octen-3-ol and is biosynthesized from the substrate linoleic acid by the sequential reaction of lipoxygenase and peroxide lyase. Here, we report for the first time the biosynthesis of (R)-(-)- 1-octen-3-ol of T. matsutake using the yeast Saccharomyces cerevisiae as a host. In this study, cDNA genes correlated with these reactions were cloned from T. matsutake, and expression studies of theses genes were carried out in the yeast Saccharomyces cerevisiae. The product of these genes expression study was carried out with Western blotting. The biosynthesis of (R)-(-)- 1-octen-3-ol of T. matsutake in recombinant Saccharomyces cerevisiae was subsequently identified with GC-MS chromatography analysis. The biosynthesis of (R)-(-)-1-octen-3-ol with S. cerevisiae represents a significant step forward.


Sujet(s)
Aldehyde-lyases/génétique , Cytochrome P-450 enzyme system/génétique , Expression des gènes , Lipoxygenase/génétique , Octanols/métabolisme , Saccharomyces cerevisiae/métabolisme , Tricholoma/enzymologie , Tricholoma/génétique , Clonage moléculaire , Fermentation , Isoenzymes , Protéines recombinantes , Température , Transformation génétique
12.
Protein Expr Purif ; 166: 105506, 2020 02.
Article de Anglais | MEDLINE | ID: mdl-31563542

RÉSUMÉ

The nuclear receptor-binding SET Domain (NSD) family consists of NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1 histone methyltransferases that are crucial for chromatin remodeling. NSDs are implicated in developmental disorders such as Wolf-Hirschhorn and Sotos syndromes as well as various cancers including t(4; 14)(p16; q32) myeloma, an incurable cancer in plasma cells. NSDs have been the target of intensive study to understand their biological functions more fully and inform anti-cancer drug design. Recombinant protein expression and purification of human NSDs using an E. coli expression system are notoriously challenging, but the production of pure, stable, and active NSDs is essential for further studies. To overcome production challenges, we propose a cost-efficient approach optimized to produce a high yield of NSDs using a modified E. coli expression system. We found that tagging the NSDs with a human influenza hemagglutinin (HA) tag greatly improved the quality of the recombinant NSDs, resulting in more than 95% pure, stable, and active NSD-HAs, with an increase in production yield up to 22.4-fold and up to 6.25 mg/L from LB E. coli culture, and without further purification such as ion-exchange or size-exclusion chromatography.


Sujet(s)
Glycoprotéine hémagglutinine du virus influenza/génétique , Histone-lysine N-methyltransferase/composition chimique , Histone-lysine N-methyltransferase/génétique , Protéines recombinantes/génétique , Séquence d'acides aminés , Chromatographie d'échange d'ions , Escherichia coli/enzymologie , Escherichia coli/génétique , Expression des gènes , Vecteurs génétiques , Glycoprotéine hémagglutinine du virus influenza/composition chimique , Humains , Protéines et peptides de signalisation intracellulaire , Conformation des protéines , Stabilité protéique , Protéines recombinantes/composition chimique
13.
Structure ; 27(4): 631-638.e8, 2019 04 02.
Article de Anglais | MEDLINE | ID: mdl-30773398

RÉSUMÉ

Histone methylation by histone methyltransferases (HMTases) has a key role in transcriptional regulation. Discrepancies between the known HMTases and the histone lysine methylome suggest that HMTases remain to be identified. Here we report the discovery, characterization, and crystal structure of Schizosaccharomyces pombe Set7, an HMTase methylating the uncharted histone H3 lysine 37 (H3K37) mark. Set7 forms a dimer with its substrate-binding site structurally specific to K37, not the neighboring well-studied K36 mark. We also discovered that H3K37 methylation levels dramatically increase during gametogenesis. Set7 deletion mutant cells show defects in gametogenesis and produce the abnormal number of spores with aberrant morphology. S. pombe gametogenesis shares similarities with mammalian spermatogenesis. These findings extend our understanding of epigenetic regulation during gametogenesis and support a link between Set7, the epigenetic H3K37 methyl mark, and proper gametogenesis.


Sujet(s)
Gamétogenèse/génétique , Histone-lysine N-methyltransferase/génétique , Histone/métabolisme , Maturation post-traductionnelle des protéines , Protéines de Schizosaccharomyces pombe/génétique , Schizosaccharomyces/génétique , Séquence d'acides aminés , Épigenèse génétique , Histone-lysine N-methyltransferase/métabolisme , Histone/génétique , Méthylation , Modèles moléculaires , Structure en hélice alpha , Structure en brin bêta , Schizosaccharomyces/croissance et développement , Schizosaccharomyces/métabolisme , Schizosaccharomyces/ultrastructure , Protéines de Schizosaccharomyces pombe/métabolisme , Alignement de séquences , Similitude de séquences d'acides aminés , Spores fongiques/génétique , Spores fongiques/croissance et développement , Spores fongiques/métabolisme , Spores fongiques/ultrastructure
14.
Biochem Biophys Res Commun ; 508(1): 102-108, 2019 01 01.
Article de Anglais | MEDLINE | ID: mdl-30471851

RÉSUMÉ

The NSD family (NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1) are histone lysine methyltransferases (HMTases) essential for chromatin regulation. The NSDs are oncoproteins, drivers of a number of tumors and are considered important drug-targets but the lack of potent and selective inhibitors hampers further therapeutic development and limits exploration of their biology. In particular, MMSET/NSD2 selective inhibition is being pursued for therapeutic interventions against multiple myeloma (MM) cases, especially in multiple myeloma t(4;14)(p16.3;q32) translocation that is associated with a significantly worse prognosis than other MM subgroups. Multiple myeloma is the second most common hematological malignancy, after non-Hodgkin lymphoma and remains an incurable malignancy. Here we report the discovery of LEM-14, an NSD2 specific inhibitor with an in vitro IC50 of 132 µM and that is inactive against the closely related NSD1 and NSD3. LEM-14-1189, a LEM-14 derivative, differentially inhibits the NSDs with in vitro IC50 of 418 µM (NSD1), IC50 of 111 µM (NSD2) and IC50 of 60 µM (NSD3). We propose LEM-14 and derivative LEM-14-1189 as tools for studying the biology of the NSDs and constitute meaningful steps toward potent NSDs therapeutic inhibitors.


Sujet(s)
Antienzymes/pharmacologie , Histone-lysine N-methyltransferase/antagonistes et inhibiteurs , Protéines oncogènes/antagonistes et inhibiteurs , Protéines de répression/antagonistes et inhibiteurs , Domaine catalytique , Conception de médicament , Découverte de médicament , Évaluation préclinique de médicament , Antienzymes/composition chimique , Histone-lysine N-methyltransferase/composition chimique , Histone-lysine N-methyltransferase/génétique , Humains , Cinétique , Modèles moléculaires , Simulation de docking moléculaire , Structure moléculaire , Conformation des protéines , Protéines de répression/composition chimique , Protéines de répression/génétique , Interface utilisateur
15.
Acta Crystallogr F Struct Biol Commun ; 72(Pt 4): 263-8, 2016 Apr.
Article de Anglais | MEDLINE | ID: mdl-27050258

RÉSUMÉ

Dysfunction of histone-modifying enzymes affects chromatin regulation and is involved in carcinogenesis, tumour progression and other diseases. Histone methyltransferases are a family of key histone-modifying enzymes, but their structures, functions and mechanisms are incompletely understood, thus constraining drug-design efforts. Here, preliminary steps towards structure-function studies of Schizosaccharomyces pombe Set7, a putative histone methyltransferase and the first yeast full-length SET-domain-containing protein to be studied using X-ray crystallography, are reported. The methods from cloning to X-ray diffraction and phasing are discussed and the results will aid in prospective studies of histone-modifying enzymes.


Sujet(s)
Protéines de Schizosaccharomyces pombe/génétique , Protéines de Schizosaccharomyces pombe/isolement et purification , Schizosaccharomyces/composition chimique , Séquence d'acides aminés , Séquence nucléotidique , Clonage moléculaire , Cristallisation , Histone méthyltransférases , Histone-lysine N-methyltransferase , Protéines de Schizosaccharomyces pombe/composition chimique
16.
Arch Biochem Biophys ; 596: 51-62, 2016 04 15.
Article de Anglais | MEDLINE | ID: mdl-26946941

RÉSUMÉ

Thermophilic l-arabinose isomerase (AI), which catalyzes the interconversion of l-arabinose and l-ribulose, can be used to produce d-tagatose, a sugar substitute, from d-galactose. Unlike mesophilic AIs, thermophilic AIs are highly dependent on divalent metal ions for their catalytic activity and thermostability at elevated temperatures. However, the molecular basis underlying the substrate preferences and metal requirements of multimeric AIs remains unclear. Here we report the first crystal structure of the apo and holo forms of thermophilic Geobacillus kaustophilus AI (GKAI) in hexamer form. The structures, including those of GKAI in complex with l-arabitol, and biochemical analyses revealed not only how the substrate-binding site of GKAI is formed through displacement of residues at the intersubunit interface when it is bound to Mn(2+), but also revealed the water-mediated H-bonding networks that contribute to the structural integrity of GKAI during catalysis. These observations suggest metal-mediated isomerization reactions brought about by intersubunit interactions at elevated temperatures are responsible for the distinct active site features that promote the substrate specificity and thermostability of thermophilic AIs.


Sujet(s)
Aldose-ketose isomerases/composition chimique , Protéines bactériennes/composition chimique , Geobacillus/enzymologie , Température élevée , Manganèse/composition chimique , Cristallographie aux rayons X , Stabilité enzymatique , Liaison hydrogène , Structure quaternaire des protéines
17.
Arch Biochem Biophys ; 585: 39-51, 2015 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-26344854

RÉSUMÉ

UDP-galactose 4-epimerase (GalE) catalyzes the interconversion of UDP-glucose (UDP-Glc) and UDP-galactose (UDP-Gal), which is a pivotal step in the Leloir pathway for d-galactose metabolism. Although GalE is widely distributed in prokaryotes and eukaryotes, little information is available regarding hyperthermophilic GalE. We overexpressed the TM0509 gene, encoding a putative GalE from Thermotoga maritima (TMGalE), in Escherichia coli and characterized the encoded protein. To further investigate the molecular basis of this enzyme's catalytic function, we determined the crystal structures of TMGalE and TMGalE bound to UDP-Glc at resolutions of 1.9 Å and 2.0 Å, respectively. The enzyme was determined to be a homodimer with a molecular mass of 70 kDa. The enzyme could reversibly catalyze the epimerization of UDP-GalNAc/UDP-GlcNAc as well as UDP-Gal/UDP-Glc at elevated temperatures, with an apparent optimal temperature and pH of 80 °C and 7.0, respectively. Our data showed that TM0509 is a UDP-galactosugar 4-epimerase involved in d-galactose metabolism; consequently, this study provides the first detailed characterization of a hyperthermophilic GalE. Moreover, the promiscuous substrate specificity of TMGalE, which is more similar to human GalE than E. coli GalE, supports the notion that TMGalE might exhibit the earliest form of sugar-epimerizing enzymes in the evolution of galactose metabolism.


Sujet(s)
Protéines bactériennes/composition chimique , Thermotoga maritima/composition chimique , UDP glucose 4-epimerase/composition chimique , Uridine diphosphate galactose/composition chimique , Uridine diphosphate glucose/composition chimique , Séquence d'acides aminés , Protéines bactériennes/antagonistes et inhibiteurs , Protéines bactériennes/génétique , Évolution biologique , Domaine catalytique , Cristallographie aux rayons X , Escherichia coli/génétique , Escherichia coli/métabolisme , Expression des gènes , Température élevée , Cinétique , Modèles moléculaires , Données de séquences moléculaires , Phylogenèse , Multimérisation de protéines , Structure secondaire des protéines , Protéines recombinantes/composition chimique , Protéines recombinantes/génétique , Alignement de séquences , Spécificité du substrat , Thermotoga maritima/classification , Thermotoga maritima/enzymologie , UDP glucose 4-epimerase/antagonistes et inhibiteurs , UDP glucose 4-epimerase/génétique
18.
J Cancer Prev ; 20(2): 113-20, 2015 Jun.
Article de Anglais | MEDLINE | ID: mdl-26151044

RÉSUMÉ

BACKGROUND: Multiple myeloma SET domain (MMSET)/nuclear receptor binding SET domain 2 (NSD2) is a lysine histone methyltransferase (HMTase) and bona fide oncoprotein found aberrantly expressed in several cancers, suggesting potential role for novel therapeutic strategies. In particular, MMSET/NSD2 is emerging as a target for therapeutic interventions against multiple myeloma, especially t(4;14) myeloma that is associated with a significantly worse prognosis than other biological subgroups. Multiple myeloma is the second most common hematological malignancy in the United States, after non-Hodgkin lymphoma and remains an incurable malignancy. Thus, effective therapeutic strategies are greatly needed. HMTases inhibitors are scarce and no NSDs inhibitors have been isolated. METHODS: We used homology modeling, molecular modeling simulations, virtual ligand screening, computational chemistry software for structure-activity relationship and performed in vitro H3K36 histone lysine methylation inhibitory assay using recombinant human NSD2-SET and human H3.1 histone. RESULTS: Here, we report the discovery of LEM-06, a hit small molecule inhibitor of NSD2, with an IC50 of 0.8 mM against H3K36 methylation in vitro. CONCLUSIONS: We propose LEM-06 as a hit inhibitor that is useful to further optimize for exploring the biology of NSD2. LEM-06 derivatives may pave the way to specific NSD2 inhibitors suitable for therapeutic efforts against malignancies.

19.
BMC Struct Biol ; 14: 25, 2014 Dec 12.
Article de Anglais | MEDLINE | ID: mdl-25494638

RÉSUMÉ

BACKGROUND: Histone lysine methylation has a pivotal role in regulating the chromatin. Histone modifiers, including histone methyl transferases (HMTases), have clear roles in human carcinogenesis but the extent of their functions and regulation are not well understood. The NSD family of HMTases comprised of three members (NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L) are oncogenes aberrantly expressed in several cancers, suggesting their potential to serve as novel therapeutic targets. However, the substrate specificity of the NSDs and the molecular mechanism of histones H3 and H4 recognition and methylation have not yet been established. RESULTS: Herein, we investigated the in vitro mechanisms of histones H3 and H4 recognition and modifications by the catalytic domain of NSD family members. In this study, we quantified in vitro mono-, di- and tri- methylations on H3K4, H3K9, H3K27, H3K36, H3K79, and H4K20 by the carboxyl terminal domain (CTD) of NSD1, NSD2 and NSD3, using histone as substrate. Next, we used a molecular modelling approach and docked 6-mer peptides H3K4 a.a. 1-7; H3K9 a.a. 5-11; H3K27 a.a. 23-29; H3K36 a.a. 32-38; H3K79 a.a. 75-81; H4K20 a.a. 16-22 with the catalytic domain of the NSDs to provide insight into lysine-marks recognition and methylation on histones H3 and H4. CONCLUSIONS: Our data highlight the versatility of NSD1, NSD2, and NSD3 for recognizing and methylating several histone lysine marks on histones H3 and H4. Our work provides a basis to design selective and specific NSDs inhibitors. We discuss the relevance of our findings for the development of NSD inhibitors amenable for novel chemotherapies.


Sujet(s)
Histone-lysine N-methyltransferase/composition chimique , Histone/métabolisme , Techniques in vitro/méthodes , Protéines et peptides de signalisation intracellulaire/composition chimique , Protéines nucléaires/composition chimique , Protéines de répression/composition chimique , Domaine catalytique , Histone méthyltransférases , Histone-lysine N-methyltransferase/génétique , Histone-lysine N-methyltransferase/métabolisme , Humains , Protéines et peptides de signalisation intracellulaire/génétique , Protéines et peptides de signalisation intracellulaire/métabolisme , Lysine/métabolisme , Méthylation , Modèles moléculaires , Protéines nucléaires/génétique , Protéines nucléaires/métabolisme , Structure secondaire des protéines , Protéines de répression/génétique , Protéines de répression/métabolisme
20.
PLoS One ; 8(2): e53840, 2013.
Article de Anglais | MEDLINE | ID: mdl-23418423

RÉSUMÉ

The navel orangeworm, Amyelois transitella is a major agricultural pest causing large losses in a variety of tree crops. Control of this insect pest may be achieved by interfering with olfactory pathways to block detection of female-produced sex pheromones and consequently, disrupt mating. The first component of this pathway is the pheromone-binding protein AtraPBP1, which recognizes the pheromone and presents it to the odorant receptor housed in a sensory neuron of the male antennae. Release of the ligand depends on a pH-induced conformational change associated with the acidity of the membrane surface. To characterize this conformational change and to understand how pheromones bind, we have determined the high resolution crystal structures of AtraPBP1 in complex with two main constituents of the sex pheromone, i.e., (11Z,13Z)-hexadecadienal and (11Z,13Z)-hexadecadienol. Comparison with the structure of the unliganded form demonstrates a large ∼90° movement of the C-terminal helix which is observed in other pheromone- or odorant-binding proteins accompanied by an unpredicted 37° displacement of the N-terminal helix. Molecular dynamic trajectories suggest that the conformational change of the α1 helix facilitates the movement of the C-terminal helix.


Sujet(s)
Protéines de transport/composition chimique , Protéines d'insecte/composition chimique , Papillons de nuit , Phéromones/composition chimique , Animaux , Concentration en ions d'hydrogène , Conformation des protéines
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