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1.
Cell ; 186(20): 4325-4344.e26, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37652010

RESUMO

KCR channelrhodopsins (K+-selective light-gated ion channels) have received attention as potential inhibitory optogenetic tools but more broadly pose a fundamental mystery regarding how their K+ selectivity is achieved. Here, we present 2.5-2.7 Å cryo-electron microscopy structures of HcKCR1 and HcKCR2 and of a structure-guided mutant with enhanced K+ selectivity. Structural, electrophysiological, computational, spectroscopic, and biochemical analyses reveal a distinctive mechanism for K+ selectivity; rather than forming the symmetrical filter of canonical K+ channels achieving both selectivity and dehydration, instead, three extracellular-vestibule residues within each monomer form a flexible asymmetric selectivity gate, while a distinct dehydration pathway extends intracellularly. Structural comparisons reveal a retinal-binding pocket that induces retinal rotation (accounting for HcKCR1/HcKCR2 spectral differences), and design of corresponding KCR variants with increased K+ selectivity (KALI-1/KALI-2) provides key advantages for optogenetic inhibition in vitro and in vivo. Thus, discovery of a mechanism for ion-channel K+ selectivity also provides a framework for next-generation optogenetics.


Assuntos
Channelrhodopsins , Rhinosporidium , Humanos , Channelrhodopsins/química , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Channelrhodopsins/ultraestrutura , Microscopia Crioeletrônica , Canais Iônicos , Potássio/metabolismo , Rhinosporidium/química
2.
Biochemistry ; 62(13): 2013-2020, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37352141

RESUMO

Function of animal and microbial rhodopsins starts by light absorption of the retinal chromophore. The absorption maximum wavelength (λmax) of rhodopsins is determined by the energy gap between the electronically ground (S0) and first excited (S1) state of the retinal chromophore, and the color tuning mechanism is one of the central topics in rhodopsin research. "Color switches", color-determining residues, are red- and blue-shifting amino acids at the same position in two rhodopsins, whose exchange causes spectral blue- and red-shifts, respectively, in each rhodopsin. As mutation easily destroys elaborate chromophore-protein interactions, the known color switches in microbial rhodopsins are limited; the L/Q switch in C-helix (TM3), the A/TS switch in G-helix (TM7), and the G/P switch in F-helix (TM6). Here, we report a novel color switch of microbial rhodopsins, which is located in D-helix (TM4). In this color switch, the red- and blue-shifting amino acids are Asn (N) and Leu (L)/Ile (I), respectively. As Asn and Leu/Ile are polar and nonpolar amino acids, respectively, and the position is located near the ß-ionone ring, the N/LI switch matches the general rule of color tuning by polarity. The N/LI switch is also useful for optogenetics, as many ion-transporting rhodopsins contain blue-shifting amino acids, such as L and I, at that position.


Assuntos
Rodopsina , Rodopsinas Microbianas , Animais , Rodopsina/química , Rodopsinas Microbianas/química , Mutação , Aminoácidos/genética , Cor
3.
Nat Cell Biol ; 25(5): 765-777, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37095322

RESUMO

PBRM1 encodes an accessory subunit of the PBAF SWI/SNF chromatin remodeller, and the inactivation of PBRM1 is a frequent event in kidney cancer. However, the impact of PBRM1 loss on chromatin remodelling is not well examined. Here we show that, in VHL-deficient renal tumours, PBRM1 deficiency results in ectopic PBAF complexes that localize to de novo genomic loci, activating the pro-tumourigenic NF-κB pathway. PBRM1-deficient PBAF complexes retain the association between SMARCA4 and ARID2, but have loosely tethered BRD7. The PBAF complexes redistribute from promoter proximal regions to distal enhancers containing NF-κB motifs, heightening NF-κB activity in PBRM1-deficient models and clinical samples. The ATPase function of SMARCA4 maintains chromatin occupancy of pre-existing and newly acquired RELA specific to PBRM1 loss, activating downstream target gene expression. Proteasome inhibitor bortezomib abrogates RELA occupancy, suppresses NF-κB activation and delays growth of PBRM1-deficient tumours. In conclusion, PBRM1 safeguards the chromatin by repressing aberrant liberation of pro-tumourigenic NF-κB target genes by residual PBRM1-deficient PBAF complexes.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Cromatina/genética , Proteínas Cromossômicas não Histona/genética , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Genômica , Neoplasias Renais/metabolismo , NF-kappa B/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética
4.
J Phys Chem Lett ; 13(40): 9539-9543, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36201035

RESUMO

Microbial and animal rhodopsins possess retinal chromophores which capture light and normally photoisomerize from all-trans to 13-cis and from 11-cis to all-trans-retinal, respectively. Here, we show that a near-infrared light-absorbing enzymerhodopsin from Obelidium mucronatum (OmNeoR) contains the all-trans form in the dark but isomerizes into the 7-cis form upon illumination. The photoproduct (λmax = 372 nm; P372) possesses a deprotonated Schiff base, and the system exhibits a bistable nature. The photochemistry of OmNeoR was arrested at <270 K, indicating the presence of a potential barrier in the excited state. Formation of P372 is accompanied by protonation changes of protonated carboxylic acids and peptide backbone changes of an α-helix. Photoisomerization from the all-trans to 7-cis retinal conformation rarely occurs in any solvent and protein environments; thus, the present study reports on a novel photochemistry mediated by a microbial rhodopsin, leading from the all-trans to 7-cis form selectively.


Assuntos
Retinaldeído , Bases de Schiff , Animais , Ácidos Carboxílicos , Luz , Retinaldeído/química , Rodopsinas Microbianas , Bases de Schiff/química , Solventes
5.
J Pathol Clin Res ; 8(5): 470-480, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35836306

RESUMO

Clear cell sarcoma of the kidney (CCSK) and primitive myxoid mesenchymal tumour of infancy (PMMTI) are paediatric sarcomas that most commonly harbour internal tandem duplications (ITDs) of exon 15 of the BCOR gene, in the range of 87-114 base pairs (bp). Some cases, instead, have BCOR-CCNB3 or YWHAE-NUTM2 gene fusions. About 10% of cases lack any of these genetic alterations when tested by standard methods. Two cases of CCSK and one PMMTI lacking the aforementioned mutations were analysed using Archer FusionPlex technology. Two related BCOR exon 15 RNA transcripts with ITDs of lengths 388 and 96 bp were detected in each case; only the 388 bp transcript was identified when genomic DNA was sequenced. In silico analysis of this transcript revealed acceptor and donor splice sites indicating that, at the RNA level, the 388-bp transcript was likely spliced to form the 96-bp transcript. The results were confirmed by Sanger sequencing using primers targeting the ITD breakpoint. This novel and unusually long ITD segment is difficult to identify by DNA sequencing using typical primer design strategies flanking entire duplicated segments because it exceeds the typical read lengths of most sequencing platforms as well as the usual fragment lengths obtained from formalin-fixed paraffin-embedded material. As diagnosis of CCSK and PMMTI may be challenging by morphology and immunohistochemistry alone, it is important to identify mutations in these cases. Knowledge of this novel BCOR ITD is important in relation to primer design for detection by sequencing, and using RNA versus DNA for sequencing.


Assuntos
Neoplasias Renais , Sarcoma , Criança , Éxons/genética , Humanos , Neoplasias Renais/patologia , Mutação , Proteínas Proto-Oncogênicas/genética , RNA , Proteínas Repressoras/genética , Sarcoma/genética , Sarcoma/patologia
6.
Nat Struct Mol Biol ; 29(6): 592-603, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35710843

RESUMO

Many organisms sense light using rhodopsins, photoreceptive proteins containing a retinal chromophore. Here we report the discovery, structure and biophysical characterization of bestrhodopsins, a microbial rhodopsin subfamily from marine unicellular algae, in which one rhodopsin domain of eight transmembrane helices or, more often, two such domains in tandem, are C-terminally fused to a bestrophin channel. Cryo-EM analysis of a rhodopsin-rhodopsin-bestrophin fusion revealed that it forms a pentameric megacomplex (~700 kDa) with five rhodopsin pseudodimers surrounding the channel in the center. Bestrhodopsins are metastable and undergo photoconversion between red- and green-absorbing or green- and UVA-absorbing forms in the different variants. The retinal chromophore, in a unique binding pocket, photoisomerizes from all-trans to 11-cis form. Heterologously expressed bestrhodopsin behaves as a light-modulated anion channel.


Assuntos
Canais Iônicos , Rodopsina , Bestrofinas , Rodopsina/química
7.
Sci Rep ; 11(1): 11478, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34075107

RESUMO

The 4F2 cell-surface antigen heavy chain (4F2hc) forms a heterodimeric complex with L-type amino acid transporter 1 (LAT1) and transports large neutral essential amino acids. However, in contrast to the traditional role of LAT1 in various cancers, the role of 4F2hc has largely remained unknown. The role of 4F2hc in prostate cancer was studied. Treatment of C4-2 cells with si4F2hc was found to suppress cellular growth, migratory and invasive abilities, with this effect occurring through the cell cycle, with a significant decrease in S phase and a significant increase in G0/G1 phase, suggesting cell cycle arrest. In addition, it was proven by RNA seq that the key to 4F2hc's impact on cancer is SKP2. si4F2hc upregulates the protein expression of cyclin-dependent kinase inhibitors (P21cip1, P27kip1) through the downstream target SKP2. Furthermore, the expression of 4F2hc and LAT1 in prostate cancer cells suggests the importance of 4F2hc. Multivariate analysis showed that high 4F2hc expression was an independent prognostic factor for progression-free survival (HR 11.54, p = 0.0357). High 4F2hc was related to the clinical tumour stage (p = 0.0255) and Gleason score (p = 0.0035). Collectively, 4F2hc contributed significantly to prostate cancer (PC) progression. 4F2hc may be a novel marker and therapeutic target in PC.


Assuntos
Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Fase G1 , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Fase de Repouso do Ciclo Celular , Proteínas Quinases Associadas a Fase S/metabolismo , Linhagem Celular Tumoral , Cadeia Pesada da Proteína-1 Reguladora de Fusão/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Proteínas Quinases Associadas a Fase S/genética
8.
Plant Cell Physiol ; 62(8): 1311-1320, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34180531

RESUMO

Chloroplast genomes in land plants include approximately 20 intron-containing genes. Most of the introns are similar to the group II introns found in fungi, algae and some bacteria, but no self-splicing has been reported. To analyze splicing reactions in chloroplasts, we developed a tobacco (Nicotiana tabacum) chloroplast-based in vitro system. We optimized the splicing reaction using atpF precursor messenger RNA (pre-mRNA). Our system requires a high ATP concentration, whereas ATP is not necessary for self-splicing group II introns. Self-splicing group II introns possess two exon-binding sites (EBS1 and 2) complementary to two intron-binding sites (IBS1 and 2) in the 3' end of 5' exons, which are involved in 5' splice-site selection. Using our in vitro system and atpF pre-mRNA, we analyzed short sequences corresponding to the above EBSs and IBSs. Mutation analyses revealed that EBS1-IBS1 pairing is essential, while EBS2-IBS2 pairing is important but not crucial for splicing. The first 3' exon nucleotide determines the 3' splice sites of self-splicing introns. However, mutations to this nucleotide in atpF pre-mRNA did not affect splicing. This result suggests that the mechanism underlying chloroplast pre-mRNA splicing differs partly from that mediating the self-splicing of group II introns.


Assuntos
Cloroplastos , Nicotiana/genética , Splicing de RNA/genética
9.
Cancer Sci ; 112(9): 3871-3883, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34050700

RESUMO

L-type amino acid transporter 3 (LAT3, SLC43A1) is abundantly expressed in prostate cancer (PC) and is thought to play an essential role in PC progression through the cellular uptake of essential amino acids. Here, we analyzed the expression, function, and downstream target of LAT3 in PC. LAT3 was highly expressed in PC cells expressing androgen receptor (AR), and its expression was increased by dihydrotestosterone treatment and decreased by bicalutamide treatment. In chromatin immunoprecipitation sequencing of AR, binding of AR to the SLC43A1 region was increased by dihydrotestosterone stimulation. Knockdown of LAT3 inhibited cell proliferation, migration, and invasion, and the phosphorylation of p70S6K and 4EBP-1. Separase (ESPL1) was identified as a downstream target of LAT3 by RNA sequencing analysis. In addition, immunostaining of prostatectomy specimens was performed. In the multivariate analysis, high expression of LAT3 was an independent prognostic factor for recurrence-free survival (hazard ratio: 3.24; P = .0018). High LAT3 expression was correlated with the pathological T stage and a high International Society of Urological Pathology grade. In summary, our results suggest that LAT3 plays an important role in the progression of PC.


Assuntos
Sistema y+L de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Separase/metabolismo , Transdução de Sinais/genética , Idoso , Sistemas de Transporte de Aminoácidos Básicos/genética , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Estudos de Coortes , Di-Hidrotestosterona/farmacologia , Progressão da Doença , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Células PC-3 , Prognóstico , Prostatectomia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Ligação Proteica/efeitos dos fármacos , Receptores Androgênicos/genética , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Transfecção
10.
Adv Exp Med Biol ; 1293: 153-165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33398812

RESUMO

The cyclic nucleotides cAMP and cGMP are ubiquitous secondary messengers that regulate multiple biological functions including gene expression, differentiation, proliferation, and cell survival. In sensory neurons, cyclic nucleotides are responsible for signal modulation, amplification, and encoding. For spatial and temporal manipulation of cyclic nucleotide dynamics, optogenetics have a great advantage over pharmacological approaches. Enzymerhodopsins are a unique family of microbial rhodopsins. These molecules are made up of a membrane-embedded rhodopsin domain, which binds an all trans-retinal to form a chromophore, and a cytoplasmic water-soluble catalytic domain. To date, three kinds of molecules have been identified from lower eukaryotes such as fungi, algae, and flagellates. Among these, histidine kinase rhodopsin (HKR) is a light-inhibited guanylyl cyclase. Rhodopsin GC (Rh-GC) functions as a light-activated guanylyl cyclase, while rhodopsin PDE (Rh-PDE) functions as a light-activated phosphodiesterase that degrades cAMP and cGMP. These enzymerhodopsins have great potential in optogenetic applications for manipulating the intracellular cyclic nucleotide dynamics of living cells. Here we introduce the molecular function and applicability of these molecules.


Assuntos
Guanilato Ciclase/metabolismo , Optogenética , Diester Fosfórico Hidrolases/metabolismo , Rodopsinas Microbianas/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Guanilato Ciclase/genética , Diester Fosfórico Hidrolases/genética , Rodopsinas Microbianas/genética
11.
Cancer Diagn Progn ; 1(3): 179-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35399311

RESUMO

Background/Aim: Recently, it was reported that the use of androgen deprivation therapy (ADT) is significantly associated with an increased risk of acute kidney injury (AKI) in patients with newly diagnosed non-metastatic prostate cancer. This study aimed to investigate the incidence of early renal dysfunction in Japanese prostate cancer patients receiving ADT and the factors associated with it. Patients and Methods: A total of 135 patients who had been pathologically diagnosed with prostate cancer and had received ADT for at least 6 months were eligible for study inclusion. The estimated glomerular filtration rate (eGFR) before treatment, and at 1, 3, and 6 months of ADT were evaluated retrospectively. We assessed renal function using eGFR and investigated the rate of change in the eGFR (ΔeGFR) during ADT. Univariate and multivariate logistic analyses were carried out to identify clinical factors that were significantly associated with renal dysfunction after 6 months ADT. Results: A total of 110 cases were evaluated in this study. The incidence of renal dysfunction after 6 months ADT was 63% (69/110). The mean ΔeGFR after 1, 3, and 6 months of ADT were -0.6%, -3.1% and -1.7%, respectively (p<0.001). Multivariate analysis showed that renal dysfunction after 3 months of ADT and hypertension were independent risk factors for renal dysfunction after 6 months ADT. Conclusion: Renal dysfunction occurs from 1 month of ADT and hypertensive prostate cancer patients receiving ADT are at high risk of developing renal dysfunction, and that such patients should be treated very carefully. Therefore, patients that are started on ADT should undergo periodic prostate-specific antigen, renal function, and urinary salt intake examinations.

12.
Int J Urol ; 28(2): 140-149, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33111429

RESUMO

Prostate cancer is a major cause of cancer-related deaths among men worldwide. In addition to genomic alterations, epigenetic alterations accumulated in prostate cancer have been elucidated. While aberrant deoxyribonucleic acid hypermethylation in promoter CpG islands inactivates crucial genes associated with deoxyribonucleic acid repair, cell cycle, apoptosis or cell adhesion, aberrant deoxyribonucleic acid hypomethylation can lead to oncogene activation. Acetylation of histone is also deregulated in prostate cancer, which could cause aberrant super-enhancer formation and activation of genes associated with cancer development. Deregulations of histone methylation, such as an increase of trimethylation at position 27 of histone H3 by enhancer of zeste homolog2 overexpression, or other modifications, such as phosphorylation and ubiquitination, are also involved in prostate cancer development, and inhibitors targeting these epigenomic aberrations might be novel therapeutic strategies. In this review, we provide an overview of epigenetic alterations in the development and progression of prostate cancer, focusing on deoxyribonucleic acid methylation and histone modifications.


Assuntos
Epigênese Genética , Neoplasias da Próstata , Ilhas de CpG , Metilação de DNA , Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Neoplasias da Próstata/genética
13.
Transl Oncol ; 14(1): 100915, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33096335

RESUMO

Primary prostate cancer (PC) progresses to castration-resistant PC (CRPC) under androgen deprivation therapy, by mechanisms e.g. expression of androgen receptor (AR) splice variant-7 (AR-V7). Here we conducted comprehensive epigenome and transcriptome analyses comparing LNCaP, primary PC cells, and LNCaP95, AR-V7-expressing CRPC cells derived from LNCaP. Of 399 AR-V7 target regions identified through ChIP-seq analysis, 377 could be commonly targeted by hormone-stimulated AR, and 22 were specifically targeted by AR-V7. Among genes neighboring to these AR-V7 target regions, 78 genes were highly expressed in LNCaP95, while AR-V7 knockdown led to significant repression of these genes and suppression of growth of LNCaP95. Of the 78 AR-V7 target genes, 74 were common AR/AR-V7 target genes and 4 were specific AR-V7 target genes; their most suppressed genes by AR-V7 knockdown were NUP210 and SLC3A2, respectively, and underwent subsequent analyses. NUP210 and SLC3A2 were significantly upregulated in clinical CRPC tissues, and their knockdown resulted in significant suppression of cellular growth of LNCaP95 through apoptosis and growth arrest. Collectively, AR-V7 contributes to CRPC proliferation by activating both common AR/AR-V7 target and specific AR-V7 target, e.g. NUP210 and SLC3A2.

14.
Int J Urol ; 28(3): 273-279, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33258172

RESUMO

OBJECTIVES: To investigate whether the result of the 1-mg dexamethasone suppression test can predict the improvement of comorbidities after adrenalectomy in patients with subclinical Cushing syndrome. METHODS: This retrospective study included 117 subclinical Cushing syndrome patients who underwent adrenalectomy. The numbers of prescribed drugs for metabolic comorbidities and the clinical variables at diagnosis were compared with those at the follow up. Patients were classified into subgroups according to the result of the 1-mg dexamethasone suppression test. RESULTS: Significant improvements in blood pressure, serum cholesterol and body mass index were observed. Furthermore, a significant improvement in glycated hemoglobin was observed in patients with diabetes mellitus. These improvements led to a discontinuation or reduction of prescribed drugs after surgery. In addition, the greatest reduction of prescribed drugs was observed in patients whose serum cortisol levels were between 1.8 and 3.0 µg/dL after the 1-mg dexamethasone suppression test. CONCLUSIONS: The result of the 1-mg dexamethasone suppression test can be a useful factor predicting the improvement of comorbidities after adrenalectomy. Current data might give us a new insight into the decision-making for the treatment of subclinical Cushing syndrome.


Assuntos
Adrenalectomia , Síndrome de Cushing , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/cirurgia , Dexametasona , Humanos , Japão/epidemiologia , Estudos Retrospectivos
15.
Nat Commun ; 11(1): 5605, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154353

RESUMO

Rhodopsin phosphodiesterase (Rh-PDE) is an enzyme rhodopsin belonging to a recently discovered class of microbial rhodopsins with light-dependent enzymatic activity. Rh-PDE consists of the N-terminal rhodopsin domain and C-terminal phosphodiesterase (PDE) domain, connected by 76-residue linker, and hydrolyzes both cAMP and cGMP in a light-dependent manner. Thus, Rh-PDE has potential for the optogenetic manipulation of cyclic nucleotide concentrations, as a complementary tool to rhodopsin guanylyl cyclase and photosensitive adenylyl cyclase. Here we present structural and functional analyses of the Rh-PDE derived from Salpingoeca rosetta. The crystal structure of the rhodopsin domain at 2.6 Å resolution revealed a new topology of rhodopsins, with 8 TMs including the N-terminal extra TM, TM0. Mutational analyses demonstrated that TM0 plays a crucial role in the enzymatic photoactivity. We further solved the crystal structures of the rhodopsin domain (3.5 Å) and PDE domain (2.1 Å) with their connecting linkers, which showed a rough sketch of the full-length Rh-PDE. Integrating these structures, we proposed a model of full-length Rh-PDE, based on the HS-AFM observations and computational modeling of the linker region. These findings provide insight into the photoactivation mechanisms of other 8-TM enzyme rhodopsins and expand the definition of rhodopsins.


Assuntos
Diester Fosfórico Hidrolases/química , Rodopsinas Microbianas/química , Coanoflagelados/enzimologia , Coanoflagelados/genética , Células HEK293 , Humanos , Modelos Moleculares , Mutação , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo , Domínios Proteicos , Rodopsina , Rodopsinas Microbianas/genética , Rodopsinas Microbianas/metabolismo , Relação Estrutura-Atividade
16.
ACS Omega ; 5(18): 10602-10609, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32426619

RESUMO

The choanoflagellate Salpingoeca rosetta contains a chimeric rhodopsin protein composed of an N-terminal rhodopsin (Rh) domain and a C-terminal cyclic nucleotide phosphodiesterase (PDE) domain. The Rh-PDE enzyme (SrRh-PDE), which decreases the concentrations of cyclic nucleotides such as cGMP and cAMP in light, is a useful tool in optogenetics. Recently, eight additional Rh-PDE enzymes were found in choanoflagellate species, four from Choanoeca flexa and the other four from other species. In this paper, we studied the molecular properties of these new Rh-PDEs, which were compared with SrRh-PDE. Upon expression in HEK293 cells, four Rh-PDE proteins, including CfRh-PDE2 and CfRh-PDE3, exhibited no PDE activity when assessed by in-cell measurements and in vitro HPLC analysis. On the other hand, CfRh-PDE1 showed light-dependent PDE activity toward cGMP, which absorbed maximally at 491 nm. Therefore, CfRh-PDE1 is presumably responsible for colony inversion in C. flexa by absorbing blue-green light. The molecular properties of MrRh-PDE were similar to those of SrRh-PDE, although the λmax of MrRh-PDE (516 nm) was considerably red-shifted from that of SrRh-PDE (492 nm). One Rh-PDE, AsRh-PDE, did not contain the retinal-binding Lys at TM7 and showed cAMP-specific PDE activity both in the dark and light. These results provide mechanistic insight into rhodopsin-mediated, light-dependent regulation of second-messenger levels in eukaryotic microbes.

17.
Sci Rep ; 10(1): 1292, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992742

RESUMO

L-type amino acid transporter 1 (LAT1) plays a role in transporting essential amino acids including leucine, which regulates the mTOR signaling pathway. Here, we studied the expression profile and functional role of LAT1 in bladder cancer. Furthermore, the pharmacological activity of JPH203, a specific inhibitor of LAT1, was studied in bladder cancer. LAT1 expression in bladder cancer cells was higher than that in normal cells. SiLAT1 and JPH203 suppressed cell proliferative and migratory and invasive abilities in bladder cancer cells. JPH203 inhibited leucine uptake by > 90%. RNA-seq analysis identified insulin-like growth factor-binding protein-5 (IGFBP-5) as a downstream target of JPH203. JPH203 inhibited phosphorylation of MAPK / Erk, AKT, p70S6K and 4EBP-1. Multivariate analysis revealed that high LAT1 expression was found as an independent prognostic factor for overall survival (HR3.46 P = 0.0204). Patients with high LAT1 and IGFBP-5 expression had significantly shorter overall survival periods than those with low expression (P = 0.0005). High LAT1 was related to the high Grade, pathological T stage, LDH, and NLR. Collectively, LAT1 significantly contributed to bladder cancer progression. Targeting LAT1 by JPH203 may represent a novel therapeutic option in bladder cancer treatment.


Assuntos
Regulação Neoplásica da Expressão Gênica , Transportador 1 de Aminoácidos Neutros Grandes/biossíntese , Sistema de Sinalização das MAP Quinases , Proteínas de Neoplasias/biossíntese , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/microbiologia , Benzoxazóis/farmacologia , Linhagem Celular Tumoral , Intervalo Livre de Doença , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Masculino , Proteínas de Neoplasias/antagonistas & inibidores , Taxa de Sobrevida , Serina-Treonina Quinases TOR/metabolismo , Tirosina/análogos & derivados , Tirosina/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia
18.
Oncotarget ; 9(50): 29316-29335, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30034620

RESUMO

Epigenome regulates gene expression to determine cell fate, and accumulation of epigenomic aberrations leads to diseases, including cancer. NCD38 inhibits lysine-specific demethylase-1 (LSD1), a histone demethylase targeting H3K4me1 and H3K4me2, but not H3K4me3. In this study, we conjugated NCD38 with a potent small molecule called pyrrole (Py) imidazole (Im) polyamide, to analyze whether targets of the inhibitor could be regulated in a sequence-specific manner. We synthesized two conjugates using ß-Ala (ß) as a linker, i.e., NCD38-ß-ß-Py-Py-Py-Py (NCD38-ß2P4) recognizing WWWWWW sequence, and NCD38-ß-ß-Py-Im-Py-Py (NCD38-ß2PIPP) recognizing WWCGWW sequence. When RKO cells were treated with NCD38, H3K4me2 levels increased in 103 regions with significant activation of nearby genes (P = 0.03), whereas H3K4me3 levels were not obviously increased. H3K27ac levels were also increased in 458 regions with significant activation of nearby genes (P = 3 × 10-10), and these activated regions frequently included GC-rich sequences, but less frequently included AT-rich sequences (P < 1 × 10-15) or WWCGWW sequences (P = 2 × 10-13). When treated with NCD38-ß2P4, 234 regions showed increased H3K27ac levels with significant activation of nearby genes (P = 2 × 10-11), including significantly fewer GC-rich sequences (P < 1 × 10-15) and significantly more AT-rich sequences (P < 1 × 10-15) compared with NCD38 treatment. When treated with NCD38-ß2PIPP, 82 regions showed increased H3K27ac levels, including significantly fewer GC-rich sequences (P = 1 × 10-11) and fewer AT-rich sequences (P = 0.005), but significantly more WWCGWW sequences (P = 0.0001) compared with NCD38 treatment. These indicated that target regions of epigenomic inhibitors could be modified in a sequence-specific manner and that conjugation of Py-Im polyamides may be useful for this purpose.

19.
Int J Urol ; 25(6): 583-588, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29651813

RESUMO

OBJECTIVES: To identify pre-treatment factors affecting the duration of post-surgical steroid replacement in patients undergoing adrenalectomy for subclinical Cushing syndrome. METHODS: The present retrospective analysis included 64 patients who underwent unilateral laparoscopic adrenalectomy for subclinical Cushing syndrome. Adrenal tumor and contralateral adrenal sizes together with various clinical factors were studied in association with the duration of post-surgical steroid replacement. Adrenal tumor and contralateral adrenal size were measured at the level of the maximum transverse plane of the adrenal glands using computed tomography scan or magnetic resonance imaging. Cox's proportional hazards model was used for the statistical analysis. RESULTS: All 64 patients were treated with post-surgical steroid replacement after adrenalectomy. The median duration of the steroid treatment was 6 months. When assessing the duration of post-surgical steroid replacement, contralateral adrenal volume <0.745 cm3 , contralateral adrenal width <6.15 mm and serum cortisol after a 1-mg dexamethasone suppression test >2.65 µg/dL were significant predictors of prolonged post-surgical steroid treatment on univariate analysis. On multivariate analysis, contralateral adrenal width <6.15 mm was the only independent predictive factor for the prolonged post-surgical steroid replacement. CONCLUSIONS: Contralateral adrenal width seems to represent a significant predictive factor for the duration of post-surgical steroid replacement in subclinical Cushing syndrome patients. Pre-surgical assessment of image findings might help clinicians determine the total duration of steroid therapy after adrenalectomy.


Assuntos
Glândulas Suprarrenais/anatomia & histologia , Adrenalectomia/efeitos adversos , Síndrome de Cushing/cirurgia , Terapia de Reposição Hormonal/métodos , Hidrocortisona/uso terapêutico , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/cirurgia , Adulto , Idoso , Síndrome de Cushing/sangue , Estudos de Viabilidade , Feminino , Humanos , Hidrocortisona/sangue , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Período Pós-Operatório , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
20.
Prostate Int ; 5(4): 143-148, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29188201

RESUMO

BACKGROUND: To investigate prognostic difference between Gleason Score (GS) 8 and 9-10, as the 2014 International Society of Urological Pathology Gleason Grading Systems proposed, in patients with prostate cancer (PCa) with bone metastasis. MATERIALS AND METHODS: We retrospectively reviewed data on 106 patients with GS 8-10 between 2006 and 2016. All patients received androgen deprivation therapy immediately. We validated biochemical recurrence, PCa-specific survival, and overall survival, and analyzed the predictive value for overall survival. RESULTS: Patients with GS 9-10 had significantly lower PCa-specific survival (50.5% vs. 83.4%, P = 0.01) and overall survival (38.8% vs. 66.3%, P = 0.04) at 5 years than those with GS 8, while biochemical recurrence rate was not significantly different (P = 0.26). Furthermore, these significant differences between GS 8 and 9-10 were also observed among high-risk groups proposed in Japan Cancer of the Prostate Risk Assessment Stratification (prostate cancer-specific survival: P = 0.03, overall survival: P = 0.04, respectively). Pathological GS 9-10 was an independent prognostic factor for overall survival (hazard ratio = 1.97, P = 0.04) in multivariable cox proportional hazard regression analysis. Among patients with GS 9-10, albumin level was an only prognostic factor for overall survival (hazard ratio = 0.33, P < 0.01). CONCLUSION: Pathological GS 9-10 predicts significantly worse outcomes than GS 8 in Japanese PCa patients with bone metastasis. Our data indicated clinical significance of discriminating the 2014 International Society of Urological Pathology Gleason Grading Group 4 and 5 among high-risk PCa patients with bone metastasis.

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