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1.
Res Sq ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38746411

RESUMEN

Heterotrimeric G proteins (Gα, Gß and Gγ) act downstream of G-protein-coupled receptors (GPCRs) to mediate signaling pathways that regulate various physiological processes and human disease conditions. Previously, human Gαi and its yeast homolog Gpa1 have been reported to function as intracellular pH sensors, yet the pH sensing capabilities of Gαi and the underlying mechanism remain to be established. Herein, we identify a pH sensing network within Gαi, and evaluate the consequences of pH modulation on the structure and stability of the G-protein. We find that changes over the physiological pH range significantly alter the structure and stability of Gαi-GDP, with the protein undergoing a disorder-to-order transition as the pH is raised from 6.8 to 7.5. Further, we find that modulation of intracellular pH in HEK293 cells regulates Gαi-Gßγ release. Identification of key residues in the pH-sensing network allowed the generation of low pH mimetics that attenuate Gαi-Gßγ release. Our findings, taken together, indicate that pH-dependent structural changes in Gαi alter the agonist-mediated Gßγ dissociation necessary for proper signaling.

3.
Mol Biotechnol ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528286

RESUMEN

There is increasing evidence indicating that global temperatures are rising significantly, a phenomenon commonly referred to as 'global warming', which in turn is believed to be causing drastic changes to the global climate. Global warming (GW) directly impacts animal health, reproduction, production, and welfare, presenting several challenges to livestock enterprises. Thermal stress (TS) is one of the key consequences of GW, and all animal species, including livestock, have diverse physiological, epigenetic and genetic mechanisms to respond to TS. As a result, TS can significantly affect an animals' health, immune responsiveness, metabolic pathways etc. which can also influence the productivity, performance, and welfare of animals. Moreover, prolonged exposure to TS can lead to transgenerational and intergenerational changes that are mediated by epigenetic changes. For example, in several animal species, the effects of TS are encoded epigenetically during the animals' growth or productive stage, and these epigenetic changes can be transmitted intergenerationally. Such epigenetic changes can affect animal productivity by changing the phenotype so that it aligns with its ancestors' environment, irrespective of its immediate environment. Furthermore, epigenetic and genetic changes can also help protect cells from the adverse effects of TS by modulating the transcriptional status of heat-responsive genes in animals. This review focuses on the genetic and epigenetic modulation and regulation that occurs in TS conditions via HSPs, histone alterations and DNA methylation.

4.
Crit Rev Oncol Hematol ; 196: 104291, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38346462

RESUMEN

Rare cancers (RCs), which account for over 20% of cancer cases, face significant research and treatment challenges due to their limited prevalence. This results in suboptimal outcomes compared to more common malignancies. Rare bone tumors (RBTs) constitute 5-10% of rare cancer cases and pose unique diagnostic complexities. The therapeutic potential of anti-cancer drugs for RBTs remains largely unexplored. Identifying molecular alterations in cancer-related genes and their associated pathways is essential for precision medicine in RBTs. Small molecule inhibitors and monoclonal antibodies targeting specific RBT-associated proteins show promise. Ongoing clinical trials aim to define RBT biomarkers, subtypes, and optimal treatment contexts, including combination therapies and immunotherapeutic agents. This review addresses the challenges in diagnosing, treating, and studying RBTs, shedding light on the current state of RBT biomarkers, potential therapeutic targets, and promising inhibitors. Rare cancers demand attention and innovative solutions to improve clinical outcomes.


Asunto(s)
Antineoplásicos , Neoplasias Óseas , Humanos , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/genética , Terapia Combinada , Medicina de Precisión , Biomarcadores
5.
Mini Rev Med Chem ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38265369

RESUMEN

Sarcoma is a heterogeneous group of malignancies often resistant to conventional chemotherapy and radiation therapy. The phosphatidylinositol-3-kinase/ protein kinase B /mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway has emerged as a critical cancer target due to its central role in regulating key cellular processes such as cell growth, proliferation, survival, and metabolism. Dysregulation of this pathway has been implicated in the development and progression of bone sarcomas (BS) and soft tissue sarcomas (STS). PI3K/Akt/mTOR inhibitors have shown promising preclinical and clinical activity in various cancers. These agents can inhibit the activation of PI3K, Akt, and mTOR, thereby reducing the downstream signaling events that promote tumor growth and survival. In addition, PI3K/Akt/mTOR inhibitors have been shown to enhance the efficacy of other anticancer therapies, such as chemotherapy and radiation therapy. The different types of PI3K/Akt/mTOR inhibitors vary in their specificity, potency, and side effect profiles and may be effective depending on the specific sarcoma type and stage. The molecular targeting of PI3K/Akt/mToR pathway using drugs, phytochemicals, nanomaterials (NMs), and microbe-derived molecules as Pan-PI3K inhibitors, selective PI3K inhibitors, and dual PI3K/mTOR inhibitors have been delineated. While there are still challenges to be addressed, the preclinical and clinical evidence suggests that these inhibitors may significantly improve patient outcomes. Further research is needed to understand the potential of these inhibitors as sarcoma therapeutics and to continue developing more selective and effective agents to meet the clinical needs of sarcoma patients.

6.
Sci Justice ; 64(1): 81-94, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38182316

RESUMEN

The human microbiome is vital for maintaining human health and has garnered substantial attention in recent years, particularly in the context of the coronavirus disease 2019 (COVID-19) outbreak. Studies have underscored significant alterations in the microbiome of COVID-19 patients across various body niches, including the gut, respiratory tract, oral cavity, skin, and vagina. These changes manifest as shifts in microbiota composition, characterized by an increase in opportunistic pathogens and a decrease in beneficial commensal bacteria. Such microbiome transformations may play a pivotal role in influencing the course and severity of COVID-19, potentially contributing to the inflammatory response. This ongoing relationship between COVID-19 and the human microbiome serves as a compelling subject of research, underscoring the necessity for further investigations into the underlying mechanisms and their implications for patient health. Additionally, these alterations in the microbiome may have significant ramifications for forensic investigations, given the microbiome's potential in establishing individual characteristics. Consequently, changes in the microbiome could introduce a level of complexity into forensic determinations. As research progresses, a more profound understanding of the human microbiome within the context of COVID-19 may offer valuable insights into disease prevention, treatment strategies, and its potential applications in forensic science. Consequently, this paper aims to provide an overarching review of microbiome alterations due to COVID-19 and the associated impact on forensic applications, bridging the gap between the altered microbiome of COVID-19 patients and the challenges forensic investigations may encounter when analyzing this microbiome as a forensic biomarker.


Asunto(s)
COVID-19 , Microbiota , Femenino , Humanos , Ciencias Forenses , Piel
7.
Int J Mol Cell Med ; 12(1): 86-99, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37942258

RESUMEN

Existing therapeutic interventions for controlling cancer are limited and associated with side effects. Furthermore, the recurrence of cancer poses a significant challenge to the cure of cancer. Therefore, avenues are wanted to find novel therapies for cancer treatment and cancer recurrence. In this review, we have highlighted that lactoferrin (LF) and activated protein C (APC) carry enormous potential in cancer treatment. Studies have shown that the decreased level of APC and impaired function of APC are associated with cancer progression and cancer-related mortality. Moreover, APC plays an important role in preventing prothrombotic state-mediated cancer progression and deaths. LF can also inhibit the progression of cancer by controlling the generation of reactive oxygen species, triggering the apoptosis of cancer cells, arresting the cell cycle and hindering the angiogenesis process. Additionally, APC and LF could have the potential to inhibit neutrophil extracellular traps (NETs) formations which are involved in cancer progression and the reawakening of dormant cancer cells. Hence, in this review, the anticancer potential and mechanism of APC and LF along with their potential to mitigate inflammation and NETs-mediated cancer progression and recurrence has been discussed. Additionally, possible future strategies to develop effective and safe anticancer treatment using LF and APC have also been discussed in this review.

8.
Artículo en Inglés | MEDLINE | ID: mdl-37249769

RESUMEN

The seafood industry generates waste, including shells, bones, intestines, and wastewater. The discards are nutrient-rich, containing varying concentrations of carotenoids, proteins, chitin, and other minerals. Thus, it is imperative to subject seafood waste, including shrimp waste (SW), to secondary processing and valorization for demineralization and deproteination to retrieve industrially essential compounds. Although several chemical processes are available for SW processing, most of them are inherently ecotoxic. Bioconversion of SW is cost-effective, ecofriendly, and safe. Microbial fermentation and the action of exogenous enzymes are among the significant SW bioconversion processes that transform seafood waste into valuable products. SW is a potential raw material for agrochemicals, microbial culture media, adsorbents, therapeutics, nutraceuticals, and bio-nanomaterials. This review comprehensively elucidates the valorization approaches of SW, addressing the drawbacks of chemically mediated methods for SW treatments. It is a broad overview of the applications associated with nutrient-rich SW, besides highlighting the role of major shrimp-producing countries in exploring SW to achieve safe, ecofriendly, and efficient bio-products.

9.
Biomolecules ; 13(2)2023 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-36830564

RESUMEN

Apoptosis is the elimination of functionally non-essential, neoplastic, and infected cells via the mitochondrial pathway or death receptor pathway. The process of apoptosis is highly regulated through membrane channels and apoptogenic proteins. Apoptosis maintains cellular balance within the human body through cell cycle progression. Loss of apoptosis control prolongs cancer cell survival and allows the accumulation of mutations that can promote angiogenesis, promote cell proliferation, disrupt differentiation, and increase invasiveness during tumor progression. The apoptotic pathway has been extensively studied as a potential drug target in cancer treatment. However, the off-target activities of drugs and negative implications have been a matter of concern over the years. Phytochemicals (PCs) have been studied for their efficacy in various cancer cell lines individually and synergistically. The development of nanoparticles (NPs) through green synthesis has added a new dimension to the advancement of plant-based nanomaterials for effective cancer treatment. This review provides a detailed insight into the fundamental molecular pathways of programmed cell death and highlights the role of PCs along with the existing drugs and plant-based NPs in treating cancer by targeting its programmed cell death (PCD) network.


Asunto(s)
Nanoestructuras , Neoplasias , Humanos , Apoptosis , Neoplasias/tratamiento farmacológico , Mitocondrias/metabolismo , Plantas , Fitoquímicos/farmacología
10.
Sci Signal ; 16(772): eabq7842, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36787384

RESUMEN

Heterotrimeric guanine nucleotide-binding proteins (G proteins) that function as molecular switches for cellular growth and metabolism are activated by GTP and inactivated by GTP hydrolysis. In uveal melanoma, a conserved glutamine residue critical for GTP hydrolysis in the G protein α subunit is often mutated in Gαq or Gα11 to either leucine or proline. In contrast, other glutamine mutations or mutations in other Gα subtypes are rare. To uncover the mechanism of the genetic selection and the functional role of this glutamine residue, we analyzed all possible substitutions of this residue in multiple Gα isoforms. Through cell-based measurements of activity, we showed that some mutants were further activated and inactivated by G protein-coupled receptors. Through biochemical, molecular dynamics, and nuclear magnetic resonance-based structural studies, we showed that the Gα mutants were functionally distinct and conformationally diverse, despite their shared inability to hydrolyze GTP. Thus, the catalytic glutamine residue contributes to functions beyond GTP hydrolysis, and these functions include subtype-specific, allosteric modulation of receptor-mediated subunit dissociation. We conclude that G proteins do not function as simple on-off switches. Rather, signaling emerges from an ensemble of active states, a subset of which are favored in disease and may be uniquely responsive to receptor-directed ligands.


Asunto(s)
Glutamina , Proteínas de Unión al GTP Heterotriméricas , Dominio Catalítico , Glutamina/genética , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Mutación , Guanosina Trifosfato/química
11.
Vet Res Commun ; 47(1): 1-16, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35781172

RESUMEN

Livestock is an essential life commodity in modern agriculture involving breeding and maintenance. The farming practices have evolved mainly over the last century for commercial outputs, animal welfare, environment friendliness, and public health. Modifying genetic makeup of livestock has been proposed as an effective tool to create farmed animals with characteristics meeting modern farming system goals. The first technique used to produce transgenic farmed animals resulted in random transgene insertion and a low gene transfection rate. Therefore, genome manipulation technologies have been developed to enable efficient gene targeting with a higher accuracy and gene stability. Genome editing (GE) with engineered nucleases-Zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) regulates the targeted genetic alterations to facilitate multiple genomic modifications through protein-DNA binding. The application of genome editors indicates usefulness in reproduction, animal models, transgenic animals, and cell lines. Recently, CRISPR/Cas system, an RNA-dependent genome editing tool (GET), is considered one of the most advanced and precise GE techniques for on-target modifications in the mammalian genome by mediating knock-in (KI) and knock-out (KO) of several genes. Lately, CRISPR/Cas9 tool has become the method of choice for genome alterations in livestock species due to its efficiency and specificity. The aim of this review is to discuss the evolution of engineered nucleases and GETs as a powerful tool for genome manipulation with special emphasis on its applications in improving economic traits and conferring resistance to infectious diseases of animals used for food production, by highlighting the recent trends for maintaining sustainable livestock production.


Asunto(s)
Sistemas CRISPR-Cas , Nucleasas de los Efectores Tipo Activadores de la Transcripción , Animales , Sistemas CRISPR-Cas/genética , Nucleasas de los Efectores Tipo Activadores de la Transcripción/genética , Nucleasas con Dedos de Zinc/genética , Edición Génica/veterinaria , Edición Génica/métodos , Mamíferos/genética , Ganado/genética
12.
Int J Mol Cell Med ; 12(3): 242-256, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38751656

RESUMEN

E. faecium is the third most common cause of nosocomial infections. Linezolid (LNZ) is a reserve antibiotic recommended for infections caused by vancomycin resistant E. faecium (VREfm).  The aim of the present study was to investigate the prevalence of optrA gene among linezolid resistant E. faecium (LREfm) and to study the molecular epidemiology using pulse field gel electrophoresis (PFGE). Clinically significant LREfm were identified and antimicrobial susceptibility was performed by disc diffusion. Minimum inhibitory concentration (MIC) of linezolid, vancomycin, daptomycin and quinupristin/dalfopristin was determined by E-test. PCR and PCR-RFPL were performed for the detection of optrA/cfr gene and G2576T mutation respectively. Molecular epidemiology was studied by PFGE. A total of 1081 clinically significant Enterococci species were isolated which included E. faecium 63.5% (n=687) and E. faecalis 36.5% (n=394). LREfm (30/687) were further studied. Multidrug resistance and vancomycin resistance was 100% and 80%, respectively. Linezolid MIC range was 8-256µg/ml and the most common mechanism of resistance was optrA gene (83.3%) followed by G2576T mutation (33.3%). PFGE analysis demonstrated 4 major clones. The optrA gene mediated linezolid resistance was high and PFGE suggests resistance was emerging in the different background strains irrespective of resistance mechanism. Studies are required to investigate factors driving the emergence of linezolid resistance. The review suggests that this is the first report of optrA-mediated resistance in E. faecium from India.

13.
Res Vet Sci ; 152: 726-735, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36270182

RESUMEN

Circular RNAs (circRNAs) are a recently identified class of RNAs produced via back-splicing and covalent linkage between RNA ends, resulting in a circularized RNA molecule. Physiologically, circRNAs are known to influence a variety of biological pathways, and can also regulate transcription, post-transcription, RNA splicing, or interaction with other proteins or microRNAs (miRNAs). Functionally, circRNAs are known to competitively bind to various other RNA molecules including miRNAs and other competing endogenous RNA such as long noncoding RNA, thereby significantly influencing gene expression. Since gene expression is a crucial factor that underlies economically important livestock traits, it is likely that circRNAs significantly influence livestock traits like growth, milk production, reproduction, meat quality, hair follicle growth, and gametogenesis. Thousands of circRNAs have been recognized in different species of animals, and some of these circRNAs have also been shown to regulate stress responses that may be crucial for animal welfare. Therefore, in this review, we aim to highlight the biogenesis of circRNAs, along with its potential implications for livestock. The presented summary would offer a fundamental understanding of the molecular machinery that underlies circRNAs and associated biological phenomena and emphasize the need for further explorations into the role of circRNAs in the other productive, reproductive, and physiological attributes in animals.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Animales , ARN Circular/genética , Ganado/genética , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética
14.
Curr Res Biotechnol ; 4: 337-349, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35942223

RESUMEN

Since December 2019 SARS-CoV-2 infections have affected millions of people worldwide. Along with the increasing number of COVID-19 patients, the number of cases of opportunistic fungal infections among the COVID-19 patients is also increasing. There have been reports of the cases of aspergillosis and candidiasis in the COVID-19 patients. The COVID-19 patients have also been affected by rare fungal infections such as histoplasmosis, pneumocystosis, mucormycosis and cryptococcosis. These fungal infections are prolonging the stay of COVID-19 patients in hospital. In this study several published case reports, case series, prospective and retrospective studies were investigated to explore and report the updated information regarding candidiasis, crytptococcosis, aspergillosis, mucormycosis, histoplasmosis, and pneumocystosis infections in COVID-19 patients. In this review, the risk factors of these co-infections in COVID-19 patients have been reported. There have been reports that the comorbidities and the treatment with corticoids, monoclonal antibodies, use of mechanical ventilation, and use of antibiotics during COVID-19 management are associated with the emergence of fungal infections in the COVID-19 patients. Hence, this review analyses the role of these therapies and comorbidities in the emergence of these fungal infections among COVID-19 patients. This review will help to comprehend if these fungal infections are the result of the co-morbidities, and treatment protocol followed to manage COVID-19 patients or directly due to the SARS-CoV-2 infection. The analysis of all these factors will help to understand their role in fungal infections among COVID-19 patients which can be valuable to the scientific community.

15.
Nucleic Acids Res ; 44(6): 2909-25, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-26762975

RESUMEN

The nuclear immunophilin FKBP25 interacts with chromatin-related proteins and transcription factors and is suggested to interact with nucleic acids. Currently the structural basis of nucleic acid binding by FKBP25 is unknown. Here we determined the nuclear magnetic resonance (NMR) solution structure of full-length human FKBP25 and studied its interaction with DNA. The FKBP25 structure revealed that the N-terminal helix-loop-helix (HLH) domain and C-terminal FK506-binding domain (FKBD) interact with each other and that both of the domains are involved in DNA binding. The HLH domain forms major-groove interactions and the basic FKBD loop cooperates to form interactions with an adjacent minor-groove of DNA. The FKBP25-DNA complex model, supported by NMR and mutational studies, provides structural and mechanistic insights into the nuclear immunophilin-mediated nucleic acid recognition.


Asunto(s)
ADN/química , Inmunofilinas/química , Proteínas de Unión a Tacrolimus/química , Secuencia de Bases , Sitios de Unión , Clonación Molecular , ADN/genética , ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Humanos , Inmunofilinas/genética , Inmunofilinas/metabolismo , Simulación del Acoplamiento Molecular , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Unión a Tacrolimus/genética , Proteínas de Unión a Tacrolimus/metabolismo , Factor de Transcripción YY1/química , Factor de Transcripción YY1/genética , Factor de Transcripción YY1/metabolismo
16.
Protein Sci ; 25(4): 905-10, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26749369

RESUMEN

Human FKBP25 (hFKBP25) is a nuclear immunophilin and interacts with several nuclear proteins, hence involving in many nuclear events. Similar to other FKBPs, FK506 binding domain (FKBD) of hFKBP25 also binds to immunosuppressive drugs such as rapamycin and FK506, albeit with a lower affinity for the latter. The molecular basis underlying this difference in affinity could not be addressed due to the lack of the crystal structure of hFKBD25 in complex with FK506. Here, we report the crystal structure of hFKBD25 in complex with FK506 determined at 1.8 Å resolution and its comparison with the hFKBD25-rapamycin complex, bringing out the microheterogeneity in the mode of interaction of these drugs, which could possibly explain the lower affinity for FK506.


Asunto(s)
Proteínas de Unión a Tacrolimus/química , Proteínas de Unión a Tacrolimus/metabolismo , Tacrolimus/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Sirolimus/metabolismo , Especificidad por Sustrato
17.
Biomol NMR Assign ; 9(1): 43-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24414276

RESUMEN

Human FKBP25, a nuclear protein, is a member of FK506 binding protein family (FKBP) and binds to immunosuppressive drugs such as FK506 and rapamycin. Human FKBP25 interacts with several nuclear proteins and regulates nuclear events. To understand the molecular basis of such interactions, we have performed NMR studies. Here, we report (1)H, (15)N and (13)C resonance assignments of the full-length human FKBP25 protein.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular , Proteínas de Unión a Tacrolimus/química , Humanos
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