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1.
J Diabetes Res ; 2024: 9066326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39444490

RESUMO

Propionate metabolism is important in the development of diabetes, and fibrosis plays an important role in diabetic nephropathy (DN). However, there are no studies on biomarkers related to fibrosis and propionate metabolism in DN. Hence, the current research is aimed at evaluating biomarkers associated with fibrosis and propionate metabolism and to explore their effect on DN progression. The GSE96804 (DN : control = 41 : 20) and GSE104948 (DN : control = 7 : 18) DN-related datasets and 924 propionate metabolism-related genes (PMRGs) and 656 fibrosis-related genes (FRGs) were acquired from the public database. First, DN differentially expressed genes (DN-DEGs) between the DN and control samples were sifted out via differential expression analysis. The PMRG scores of the DN samples were calculated based on PMRGs. The samples were divided into the high and low PMRG score groups according to the median scores. The PM-DEGs between the two groups were screened out. Second, the intersection of DN-DEGs, PM-DEGs, and FRGs was taken to yield intersected genes. Random forest (RF) and recursive feature elimination (RFE) analyses of the intersected genes were performed to sift out biomarkers. Then, single gene set enrichment analysis was conducted. Finally, immunoinfiltrative analysis was performed, and the transcription factor (TF)-microRNA (miRNA)-mRNA regulatory network and the drug-gene interaction network were constructed. There were 2633 DN-DEGs between the DN and control samples and 515 PM-DEGs between the high and low PMRG score groups. In total, 10 intersected genes were gained after taking the intersection of DN-DEGs, PM-DEGs, and FRGs. Seven biomarkers, namely, SLC37A4, ACOX2, GPD1, angiotensin-converting enzyme 2 (ACE2), SLC9A3, AGT, and PLG, were acquired via RF and RFE analyses, and they were found to be involved in various mechanisms such as glomerulus development, fatty acid metabolism, and peroxisome. The seven biomarkers were positively correlated with neutrophils. Moreover, 8 TFs, 60 miRNAs, and 7 mRNAs formed the TF-miRNA-mRNA regulatory network, including USF1-hsa-mir-1296-5p-AGT and HIF1A-hsa-mir-449a-5p-ACE2. The drug-gene network contained UROKINASE-PLG, ATENOLOL-AGT, and other interaction relationship pairs. Via bioinformatic analyses, the risk of fibrosis and propionate metabolism-related biomarkers in DN were explored, thereby providing novel ideas for research related to DN diagnosis and treatment.


Assuntos
Biomarcadores , Nefropatias Diabéticas , Fibrose , Perfilação da Expressão Gênica , Propionatos , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Humanos , Fibrose/genética , Biomarcadores/metabolismo , Propionatos/metabolismo , Redes Reguladoras de Genes , Bases de Dados Genéticas , MicroRNAs/genética , MicroRNAs/metabolismo , Biologia Computacional
2.
Int J Mol Sci ; 25(20)2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39456717

RESUMO

Electron transfer flavoprotein (ETF) plays an important function in fatty acid beta oxidation and the amino acid metabolic pathway. It can provide pathogenicity to some opportunistic fungi via modulating cellular metabolite composition. Arthrobotrys oligospora is a typical invasion fungus to nematodes. Its ETF characterization is still unknown. Here, we showed that the mutations of A. oligospora ETF (Aoetfα and Aoetfß) and its dehydrogenase (Aoetfdh) led to severe defects in mitochondrial integrity and blocked fatty acid metabolism. The pathogenicity-associated trap structures were completely suppressed when exposed to nematode-derived ascarosides and nutrition signals, including ammonia and urea. Compared to the wild-type strain, the nematode predatory activity was significantly reduced and delayed. But surprisingly, the rich nutrition could restore the massive trap and robust predatory activity in the mutant Aoetfß beyond all induction cues. Moreover, the deletion of Aoetfß has led to the accumulation of butyrate-like smell, which has a strong attraction to Caenorhabditis elegans nematodes. Ultimately, ETF and its dehydrogenase play a crucial role in nematode-trapping fungi, highlighting mitochondrial metabolite fluctuations that are connected to pathogenesis and further regulating the interactions between fungi and nematodes.


Assuntos
Ascomicetos , Caenorhabditis elegans , Flavoproteínas Transferidoras de Elétrons , Flavoproteínas Transferidoras de Elétrons/metabolismo , Flavoproteínas Transferidoras de Elétrons/genética , Animais , Ascomicetos/patogenicidade , Ascomicetos/genética , Ascomicetos/enzimologia , Caenorhabditis elegans/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Mitocôndrias/metabolismo , Mutação , Oxirredutases/metabolismo , Oxirredutases/genética , Virulência/genética , Ácidos Graxos/metabolismo
3.
Langmuir ; 40(43): 22504-22515, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39412192

RESUMO

Antifouling surfaces, renowned for their strong surface resistance to proteins, cells, or tissues in various biological and environmental conditions, have broad applications in implanted devices, antibacterial coatings, biosensors, responsive materials, water treatment, and lab-on-a-chip. While extensive experimental research exists on antifouling surfaces, machine learning studies on this topic are relatively few. This perspective specifically focuses on exploring the complex relationships between the composition, structure, and properties of antifouling surfaces, examining how these factors correlate with surface hydration and protein adsorption. Different machine learning models have been developed to analyze and predict single and multiple protein adsorptions on various types of surfaces, ranging from structureless surfaces to well-ordered and rigid self-assembled monolayers, dynamically ordered polymer brushes, and complex filtration membranes. These models not only identify key descriptors or functional groups critical for antifouling performance (surface hydration, protein adsorption) but also predict the antifouling properties for a specific surface. Recognizing current challenges, this perspective delineates future research directions in the antifouling field. By leveraging and comparing current machine learning approaches, it aims to advance both the design and fundamental understanding of antifouling surfaces, thereby pushing the boundaries of innovation in this critical field.

4.
J Phys Chem B ; 128(39): 9315-9326, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39314090

RESUMO

Cyclin-dependent kinases (CDKs) are activated upon cyclin-binding to enable progression through the cell cycle. Dominant CDKs and cyclins in mammalian cells include CDK1, CDK2, CDK4, and CDK6 and corresponding cyclins A, B, D, and E. While only certain, "typical" cyclin/CDK complexes are primarily responsible for cell cycle progression, "atypical" cyclin/CDK complexes can form and sometimes perform the same roles as typical complexes. We asked what structural features of cyclins and CDKs favor the formation of typical complexes, a vital yet not fully explored question. We use computational docking and biophysical analyses to exhaustively evaluate the structure and stability of all CDK and cyclin complexes listed above. We find that binding of the complexes is generally stronger for typical than for atypical complexes, especially when the CDK is in an active conformation. Typical complexes have denser clusters, indicating that they have more defined cyclin-binding sites than atypical complexes. Our results help explain three notable features of cyclin/CDK function in the cell cycle: (i) why CDK4 and cyclin-D have exceptionally high specificity for each other; (ii) why both cyclin-A and cyclin-B strongly activate CDK1, whereas CDK2 is only strongly activated by cyclin-A; and (iii) why cyclin-E normally activates CDK2 but not CDK1. Overall, this work reveals the binding modalities of cyclin/CDK complexes, how the modalities lead to the preference for typical complexes versus atypical complexes, and how binding modalities differ between typical complexes. Our observations suggest targeting CDK catalytic actions through destabilizing their native differential cyclin interfaces.


Assuntos
Ciclo Celular , Quinases Ciclina-Dependentes , Ciclinas , Ligação Proteica , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/química , Ciclinas/metabolismo , Ciclinas/química , Humanos , Sítios de Ligação , Simulação de Acoplamento Molecular
5.
Chem Soc Rev ; 53(17): 8713-8763, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39041297

RESUMO

Amyloid peptides (AMYs) and antimicrobial peptides (AMPs) are considered as the two distinct families of peptides, characterized by their unique sequences, structures, biological functions, and specific pathological targets. However, accumulating evidence has revealed intriguing pathological connections between these peptide families in the context of microbial infection and neurodegenerative diseases. Some AMYs and AMPs share certain structural and functional characteristics, including the ability to self-assemble, the presence of ß-sheet-rich structures, and membrane-disrupting mechanisms. These shared features enable AMYs to possess antimicrobial activity and AMPs to acquire amyloidogenic properties. Despite limited studies on AMYs-AMPs systems, the cross-seeding phenomenon between AMYs and AMPs has emerged as a crucial factor in the bidirectional communication between the pathogenesis of neurodegenerative diseases and host defense against microbial infections. In this review, we examine recent developments in the potential interplay between AMYs and AMPs, as well as their pathological implications for both infectious and neurodegenerative diseases. By discussing the current progress and challenges in this emerging field, this account aims to inspire further research and investments to enhance our understanding of the intricate molecular crosstalk between AMYs and AMPs. This knowledge holds great promise for the development of innovative therapies to combat both microbial infections and neurodegenerative disorders.


Assuntos
Peptídeos Antimicrobianos , Doenças Neurodegenerativas , Humanos , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Proteínas Amiloidogênicas/metabolismo , Proteínas Amiloidogênicas/química , Proteínas Amiloidogênicas/antagonistas & inibidores , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia
6.
Sci Adv ; 10(27): eadm9211, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38968359

RESUMO

Decades ago, mitogen-promoted signaling duration and strength were observed to be sensed by the cell and to be critical for its decisions: to proliferate or differentiate. Landmark publications established the importance of mitogen signaling not only in the G1 cell cycle phase but also through the S and the G2/M transition. Despite these early milestones, how mitogen signal duration and strength, short and strong or weaker and sustained, control cell fate has been largely unheeded. Here, we center on cardinal signaling-related questions, including (i) how fluctuating mitogenic signals are converted into cell proliferation-differentiation decisions and (ii) why extended duration of weak signaling is associated with differentiation, while bursts of strong and short induce proliferation but, if too strong and long, induce irreversible senescence. Our innovative broad outlook harnesses cell biology and protein conformational ensembles, helping us to define signaling strength, clarify cell cycle decisions, and thus cell fate.


Assuntos
Ciclo Celular , Diferenciação Celular , Transdução de Sinais , Humanos , Animais , Mitógenos/metabolismo , Proliferação de Células
7.
JACS Au ; 4(5): 1911-1927, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38818077

RESUMO

Cyclin-dependent kinases (CDKs), particularly CDK4 and CDK2, are crucial for cell cycle progression from the Gap 1 (G1) to the Synthesis (S) phase by phosphorylating targets such as the Retinoblastoma Protein (Rb). CDK4, paired with cyclin-D, operates in the long G1 phase, while CDK2 with cyclin-E, manages the brief G1-to-S transition, enabling DNA replication. Aberrant CDK signaling leads to uncontrolled cell proliferation, which is a hallmark of cancer. Exactly how they accomplish their catalytic phosphorylation actions with distinct efficiencies poses the fundamental, albeit overlooked question. Here we combined available experimental data and modeling of the active complexes to establish their conformational functional landscapes to explain how the two cyclin/CDK complexes differentially populate their catalytically competent states for cell cycle progression. Our premise is that CDK catalytic efficiencies could be more important for cell cycle progression than the cyclin-CDK biochemical binding specificity and that efficiency is likely the prime determinant of cell cycle progression. We observe that CDK4 is more dynamic than CDK2 in the ATP binding site, the regulatory spine, and the interaction with its cyclin partner. The N-terminus of cyclin-D acts as an allosteric regulator of the activation loop and the ATP-binding site in CDK4. Integrated with a suite of experimental data, we suggest that the CDK4 complex is less capable of remaining in the active catalytically competent conformation, and may have a lower catalytic efficiency than CDK2, befitting their cell cycle time scales, and point to critical residues and motifs that drive their differences. Our mechanistic landscape may apply broadly to kinases, and we propose two drug design strategies: (i) allosteric Inhibition by conformational stabilization for targeting allosteric CDK4 regulation by cyclin-D, and (ii) dynamic entropy-optimized targeting which leverages the dynamic, entropic aspects of CDK4 to optimize drug binding efficacy.

8.
Chem Sci ; 15(19): 7285-7292, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38756801

RESUMO

Energy-efficient separation of C2H6/C2H4 is a great challenge, for which adsorptive separation is very promising. C2H6-selective adsorption has big implications, while the design of C2H6-sorbents with ideal adsorption capability, particularly with the C2H6/C2H4-selectivity exceeded 2.0, is still challenging. Instead of the current strategies such as chemical modification or pore space modulation, we propose a new methodology for the design of C2H6-sorbents. With a Cu-TCPP [TCPP = 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin] framework dispersed onto a microporous carbon and a hierarchical-pore carbon, two composite sorbents are fabricated. The composite sorbents exhibit enhanced C2H6-selective adsorption capabilities with visible light, particularly the composite sorbent based on the hierarchical-pore carbon, whose C2H6 and C2H4 adsorption capacities (0 °C, 1 bar) are targetedly increased by 27% and only 1.8% with visible light, and therefore, an C2H6-selectivity (C2H6/C2H4 = 10/90, v/v) of 4.8 can be realized. With visible light, the adsorption force of the C2H6 molecule can be asymmetrically enhanced by the excitation enriched electron density over the adsorption sites formed via the close interaction between the Cu-TCPP and the carbon layer, whereas that of the C2H4 molecule is symmetrically altered and the forces cancelled each other out. This strategy may open up a new route for energy-efficient adsorptive separation of C2H6/C2H4 with light.

9.
J Phys Chem B ; 128(21): 5175-5187, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38747619

RESUMO

SHP2 is a positive regulator of the EGFR-dependent Ras/MAPK pathway. It dephosphorylates a regulatory phosphorylation site in EGFR that serves as the binding site to RasGAP (RASA1 or p120RasGAP). RASA1 is activated by binding to the EGFR phosphate group. Active RASA1 deactivates Ras by hydrolyzing Ras-bound GTP to GDP. Thus, SHP2 dephosphorylation of EGFR effectively prevents RASA1-mediated deactivation of Ras, thereby stimulating proliferation. Despite knowledge of this vital regulation in cell life, mechanistic in-depth structural understanding of the involvement of SHP2, EGFR, and RASA1 in the Ras/MAPK pathway has largely remained elusive. Here we elucidate the interactions, the factors influencing EGFR's recruitment of RASA1, and SHP2's recognition of the substrate site in EGFR. We reveal that RASA1 specifically interacts with the DEpY992LIP motif in EGFR featuring a proline residue at the +3 position C-terminal to pY primarily through its nSH2 domain. This interaction is strengthened by the robust attraction of two acidic residues, E991 and D990, of EGFR to two basic residues in the BC-loop near the pY-binding pocket of RASA1's nSH2. In the stable precatalytic state of SHP2 with EGFR (DADEpY992LIPQ), the E-loop of SHP2's active site favors the interaction with the (-2)-position D990 and (-4)-position D988 N-terminal to pY992 in EGFR, while the pY-loop constrains the (+4)-position Q996 C-terminal to pY992. These specific interactions not only provide a structural basis for identifying negative regulatory sites in other RTKs but can inform selective, high-affinity active-site SHP2 inhibitors tailored for SHP2 mutants.


Assuntos
Receptores ErbB , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteína p120 Ativadora de GTPase , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/química , Humanos , Fosforilação , Proteína p120 Ativadora de GTPase/metabolismo , Proteína p120 Ativadora de GTPase/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/metabolismo , Ligação Proteica , Sítios de Ligação
10.
Structure ; 32(8): 1269-1280.e2, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38703777

RESUMO

Dysregulation of cyclin-dependent kinases (CDKs) impacts cell proliferation, driving cancer. Here, we ask why the cyclin-D/CDK4 complex governs cell cycle progression through the longer G1 phase, whereas cyclin-E/CDK2 regulates the shorter G1/S phase transition. We consider available experimental cellular and structural data including cyclin-E's high-level burst, sustained duration of elevated cyclin-D expression, and explicit solvent molecular dynamics simulations of the inactive monomeric and complexed states, to establish the conformational tendencies along the landscape of the distinct activation scenarios of cyclin-D/CDK4 and cyclin-E/CDK2 in the G1 phase and G1/S transition of the cell cycle, respectively. These lead us to propose slower activation of cyclin-D/CDK4 and rapid activation of cyclin-E/CDK2. We provide the mechanisms through which this occurs, offering innovative CDK4 drug design considerations. Our insightful mechanistic work addresses a compelling cell cycle regulation question and illuminates the distinct activation speeds between the G1 and the G1/S phases, which are crucial for function.


Assuntos
Ciclo Celular , Quinase 2 Dependente de Ciclina , Quinase 4 Dependente de Ciclina , Simulação de Dinâmica Molecular , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 2 Dependente de Ciclina/química , Quinase 2 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/química , Humanos , Ligação Proteica , Ciclina E/metabolismo , Ciclina E/química , Ciclina E/genética , Ciclina D/metabolismo , Ciclina D/química , Ciclina D/genética , Sítios de Ligação , Ativação Enzimática
11.
Chem Sci ; 15(3): 1003-1017, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38239681

RESUMO

mTOR serine/threonine kinase is a cornerstone in the PI3K/AKT/mTOR pathway. Yet, the detailed mechanism of activation of its catalytic core is still unresolved, likely due to mTOR complexes' complexity. Its dysregulation was implicated in cancer and neurodevelopmental disorders. Using extensive molecular dynamics (MD) simulations and compiled published experimental data, we determine exactly how mTOR's inherent motifs can control the conformational changes in the kinase domain, thus kinase activity. We also chronicle the critical regulation by the unstructured negative regulator domain (NRD). When positioned inside the catalytic cleft (NRD IN state), mTOR tends to adopt a deep and closed catalytic cleft. This is primarily due to the direct interaction with the FKBP-rapamycin binding (FRB) domain which restricts it, preventing substrate access. Conversely, when outside the catalytic cleft (NRD OUT state), mTOR favors an open conformation, exposing the substrate-binding site on the FRB domain. We further show how an oncogenic mutation (L2427R) promotes shifting the mTOR ensemble toward the catalysis-favored state. Collectively, we extend mTOR's "active-site restriction" mechanism and clarify mutation action. In particular, our mechanism suggests that RMC-5552 (RMC-6272) bitopic inhibitors may benefit from adjustment of the (PEG8) linker length when targeting certain mTOR variants. In the cryo-EM mTOR/RMC-5552 structure, the distance between the allosteric and orthosteric inhibitors is ∼22.7 Å. With a closed catalytic cleft, this linker bridges the sites. However, in our activation mechanism, in the open cleft it expands to ∼24.7 Å, offering what we believe to be the first direct example of how discovering an activation mechanism can potentially increase the affinity of inhibitors targeting mutants.

12.
Langmuir ; 40(2): 1487-1502, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38153400

RESUMO

Polymer brushes have witnessed extensive utilization and progress, driven by their distinct attributes in surface modification, tethered group functionality, and tailored interactions at the nanoscale, enabling them for various scientific and industrial applications of coatings, sensors, switchable/responsive materials, nanolithography, and lab-on-a-chips. Despite the wealth of experimental investigations into polymer brushes, this review primarily focuses on computational studies of antifouling polymer brushes with a strong emphasis on achieving a molecular-level understanding and structurally designing antifouling polymer brushes. Computational exploration covers three realms of thermotical models, molecular simulations, and machine-learning approaches to elucidate the intricate relationship between composition, structure, and properties concerning polymer brushes in the context of nanotribology, surface hydration, and packing conformation. Upon acknowledging the challenges currently faced, we extend our perspectives toward future research directions by delineating potential avenues and unexplored territories. Our overarching objective is to advance our foundational comprehension and practical utilization of polymer brushes for antifouling applications, leveraging the synergy between computational methods and materials design to drive innovation in this crucial field.

13.
Cell Mol Life Sci ; 81(1): 5, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085330

RESUMO

SHP2 phosphatase promotes full activation of the RTK-dependent Ras/MAPK pathway. Its mutations can drive cancer and RASopathies, a group of neurodevelopmental disorders (NDDs). Here we ask how same residue mutations in SHP2 can lead to both cancer and NDD phenotypes, and whether we can predict what the outcome will be. We collected and analyzed mutation data from the literature and cancer databases and performed molecular dynamics simulations of SHP2 mutants. We show that both cancer and Noonan syndrome (NS, a RASopathy) mutations favor catalysis-prone conformations. As to cancer versus RASopathies, we demonstrate that cancer mutations are more likely to accelerate SHP2 activation than the NS mutations at the same genomic loci, in line with NMR data for K-Ras4B more aggressive mutations. The compiled experimental data and dynamic features of SHP2 mutants lead us to propose that different from strong oncogenic mutations, SHP2 activation by NS mutations is less likely to induce a transition of the ensemble from the SHP2 inactive state to the active state. Strong signaling promotes cell proliferation, a hallmark of cancer. Weak, or moderate signals are associated with differentiation. In embryonic neural cells, dysregulated differentiation is connected to NDDs. Our innovative work offers structural guidelines for identifying and correlating mutations with clinical outcomes, and an explanation for why bearers of RASopathy mutations may have a higher probability of cancer. Finally, we propose a drug strategy against SHP2 variants-promoting cancer and RASopathies.


Assuntos
Neoplasias , Síndrome de Noonan , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Síndrome de Noonan/genética , Mutação/genética , Neoplasias/genética , Domínios de Homologia de src/genética , Fenótipo
14.
RSC Chem Biol ; 4(11): 850-864, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37920394

RESUMO

The sequence-structure-function paradigm has dominated twentieth century molecular biology. The paradigm tacitly stipulated that for each sequence there exists a single, well-organized protein structure. Yet, to sustain cell life, function requires (i) that there be more than a single structure, (ii) that there be switching between the structures, and (iii) that the structures be incompletely organized. These fundamental tenets called for an updated sequence-conformational ensemble-function paradigm. The powerful energy landscape idea, which is the foundation of modernized molecular biology, imported the conformational ensemble framework from physics and chemistry. This framework embraces the recognition that proteins are dynamic and are always interconverting between conformational states with varying energies. The more stable the conformation the more populated it is. The changes in the populations of the states are required for cell life. As an example, in vivo, under physiological conditions, wild type kinases commonly populate their more stable "closed", inactive, conformations. However, there are minor populations of the "open", ligand-free states. Upon their stabilization, e.g., by high affinity interactions or mutations, their ensembles shift to occupy the active states. Here we discuss the role of conformational propensities in function. We provide multiple examples of diverse systems, including protein kinases, lipid kinases, and Ras GTPases, discuss diverse conformational mechanisms, and provide a broad outlook on protein ensembles in the cell. We propose that the number of molecules in the active state (inactive for repressors), determine protein function, and that the dynamic, relative conformational propensities, rather than the rigid structures, are the hallmark of cell life.

15.
Curr Opin Struct Biol ; 83: 102722, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37871498

RESUMO

Proteins exist as dynamic conformational ensembles. Here we suggest that the propensities of the conformations can be predictors of cell function. The conformational states that the molecules preferentially visit can be viewed as phenotypic determinants, and their mutations work by altering the relative propensities, thus the cell phenotype. Our examples include (i) inactive state variants harboring cancer driver mutations that present active state-like conformational features, as in K-Ras4BG12V compared to other K-Ras4BG12X mutations; (ii) mutants of the same protein presenting vastly different phenotypic and clinical profiles: cancer and neurodevelopmental disorders; (iii) alterations in the occupancies of the conformational (sub)states influencing enzyme reactivity. Thus, protein conformational propensities can determine cell fate. They can also suggest the allosteric drugs efficiency.


Assuntos
Neoplasias , Proteínas , Humanos , Conformação Proteica , Fenótipo
16.
bioRxiv ; 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37790340

RESUMO

Dysregulation of cyclin-dependent kinases (CDKs) impacts cell proliferation, driving cancer. Here, we ask why the cyclin-D/CDK4 complex governs cell cycle progression through the longer G1 phase, whereas cyclin-E/CDK2 regulates the short G1/S phase transition. We consider the experimentally established high-level bursting of cyclin-E, and sustained duration of elevated cyclin-D expression in the cell, available experimental cellular and structural data, and comprehensive explicit solvent molecular dynamics simulations to provide the mechanistic foundation of the distinct activation scenarios of cyclin-D/CDK4 and cyclin-E/CDK2 in the G1 phase and G1/S transition of the cell cycle, respectively. These lead us to propose slower activation of cyclin-D/CDK4 and rapid activation of cyclin-E/CDK2. Importantly, we determine the mechanisms through which this occurs, offering innovative CDK4 drug design considerations. Our insightful mechanistic work addresses the compelling cell cycle regulation question and illuminates the distinct activation speeds in the G1 versus G1/S phases, which are crucial for cell function.

17.
Pest Manag Sci ; 79(11): 4557-4568, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37431839

RESUMO

BACKGROUND: Entomopathogenic fungi (EPF) are multifunctional microorganisms acting not only as biopesticides against insect pests but also as endophytes which regulate plant growth. The tomato leafminer, Phthorimaea absoluta (Tuta absoluta) is a devastating invasive pest of tomatoes worldwide. However, effective alternatives are needed for a sustainable management of this invasive pest. In this study, the functional effects of five EPF isolates Metarhizium flavoviride, M. anisopliae, M. rileyi, Cordyceps fumosorosea and Beauveria bassiana were evaluated on tomato growth promotion and pest protection against P. absoluta. RESULTS: When directly sprayed with conidia, P. absoluta larvae showed high cumulative mortality of 100% to M. anisopliae under 1 × 108 conidia/mL, whereas M. flavoviride, B. bassiana, C. fumosorosea and M. rileyi caused cumulative mortality of 92.65%, 92.62%, 92.16% and 68.95%, respectively. Moreover, all five EPF isolates can successfully colonize tomato plants, whilst the colonization rate for each EPF depends on the inoculation method used. The most efficient inoculation method for M. flavoviride and M. rileyi was root dipping, for M. anisopliae and C. fumosorosea it was coating seed, and for B. bassiana it was foliage spraying. The highest plant colonization was obtained by M. flavoviride. Meanwhile, all these isolates promoted tomato plant growth upon inoculation. Furthermore, endophytic colonization of plants by the five EPF negatively affected the performance of P. absoluta, among them M. anisopliae and C. fumosorosea showed strong negative effects on the performance of P. absoluta. CONCLUSION: Our results highlight the potential of incorporating entomopathogenic fungi as endophytes in integrated pest management practices to protect tomatoes against P. absoluta. © 2023 Society of Chemical Industry.

18.
Biophys Rev ; 15(2): 163-181, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37124926

RESUMO

Neurodevelopmental disorders (NDDs) and cancer share proteins, pathways, and mutations. Their clinical symptoms are different. However, individuals with NDDs have higher probabilities of eventually developing cancer. Here, we review the literature and ask how the shared features can lead to different medical conditions and why having an NDD first can increase the chances of malignancy. To explore these vital questions, we focus on dysregulated PI3K/mTOR, a major brain cell growth pathway in differentiation, and MAPK, a critical pathway in proliferation, a hallmark of cancer. Differentiation is governed by chromatin organization, making aberrant chromatin remodelers highly likely agents in NDDs. Dysregulated chromatin organization and accessibility influence the lineage of specific cell brain types at specific embryonic development stages. PAK1, with pivotal roles in brain development and in cancer, also regulates MAPK. We review, clarify, and connect dysregulated pathways with dysregulated proliferation and differentiation in cancer and NDDs and highlight PAK1 role in brain development and MAPK regulation. Exactly how PAK1 activation controls brain development, and why specific chromatin remodeler components, e.g., BAF170 encoded by SMARCC2 in autism, await clarification.

19.
Angew Chem Int Ed Engl ; 62(27): e202304367, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37156725

RESUMO

The photo-responsive adsorption has emerged as a vibrant area, but its current methodology is limited by the well-defined photochromic units and their molecular deformation driven by photo-stimuli. Herein, a methodology of nondeforming photo-responsiveness is successfully exploited. With the exploiting agent of Cu-TCPP framework assembled on the graphite and strongly interacted with it, the sorbent generates two kinds of adsorption sites, over which the electron density distribution of the graphite layer can be modulated at the c-axis direction, which can further evolve due to photo-stimulated excited states. The excited states are stable enough to meet the timescale of microscopic adsorption equilibrium. Independent of the ultra-low specific surface area of the sorbent (20 m2 g-1 ), the CO adsorption capability can be improved from 0.50 mmol g-1 at the ground state to 1.24 mmol g-1 (0 °C, 1 bar) with the visible light radiation, rather than the photothermal desorption.

20.
Drug Discov Today ; 28(6): 103551, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36907321

RESUMO

Drug discovery is arguably a highly challenging and significant interdisciplinary aim. The stunning success of the artificial intelligence-powered AlphaFold, whose latest version is buttressed by an innovative machine-learning approach that integrates physical and biological knowledge about protein structures, raised drug discovery hopes that unsurprisingly, have not come to bear. Even though accurate, the models are rigid, including the drug pockets. AlphaFold's mixed performance poses the question of how its power can be harnessed in drug discovery. Here we discuss possible ways of going forward wielding its strengths, while bearing in mind what AlphaFold can and cannot do. For kinases and receptors, an input enriched in active (ON) state models can better AlphaFold's chance of rational drug design success.


Assuntos
Inteligência Artificial , Descoberta de Drogas , Sítio Alostérico , Proteínas/química , Desenho de Fármacos , Regulação Alostérica
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