Journal of Molecular Biology最新文献

{"title":"Cryo-EM Detection of AMPylated Histidine Implies Covalent Catalysis in AMPylation Mediated by a Bacterial Effector","authors":"Zhengrui Zhang ,&nbsp;Rishi Patel ,&nbsp;Zhao-Qing Luo ,&nbsp;Chittaranjan Das","doi":"10.1016/j.jmb.2024.168917","DOIUrl":"10.1016/j.jmb.2024.168917","url":null,"abstract":"<div><div>AMPylation is a post-translational modification (PTM) whereby adenosine monophosphate (AMP) from adenosine triphosphate (ATP) is transferred onto protein hydroxyl groups of serine, threonine, or tyrosine. Recently, an actin-dependent AMPylase namely LnaB from the bacterial pathogen <em>Legionella pneumophila</em> was found to AMPylate phosphate groups of phosphoribosylated ubiquitin and Src family kinases. LnaB represents an evolutionarily distinct family of AMPylases with conserved active site Ser-His-Glu residues. Here, we capture the structure of the LnaB-actin complex in a putative intermediate state via single-particle cryogenic electron microscopy (cryo-EM) and find that the catalytic histidine of LnaB is covalently attached to AMP through a phosphoramidate linkage at the Nδ1 atom. This observation provides direct structural evidence of histidine AMPylation as a PTM and implies the possibility of covalent catalysis in LnaB-mediated AMPylation, a mechanism distinct from known AMPylases. Subsequent biochemical studies confirm the observed AMP binding site and provide additional insights into the catalytic properties of LnaB. Together, our work highlights the power of cryo-EM in capturing labile PTMs and transient species during enzymatic reactions, while opening new avenues of mechanistic investigation into the LnaB family.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 3","pages":"Article 168917"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142851953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conversion of Human Multidrug Transporter P-glycoprotein (ABCB1) from Drug Efflux to Uptake Pump: Evidence for a Switch Region Modulating the Direction of Substrate Transport","authors":"Andaleeb Sajid,&nbsp;Nandhini Ranganathan,&nbsp;Rajan Guha,&nbsp;Megumi Murakami,&nbsp;Shafaq Ahmed,&nbsp;Stewart R. Durell,&nbsp;Suresh V. Ambudkar","doi":"10.1016/j.jmb.2025.168979","DOIUrl":"10.1016/j.jmb.2025.168979","url":null,"abstract":"<div><div>The multidrug transporter P-glycoprotein (P-gp), is pivotal in exporting various chemically dissimilar amphipathic compounds including anti-cancer drugs, thus causing multidrug resistance during cancer treatment. P-gp is composed of two transmembrane domains (TMDs), each containing six homologous transmembrane helices (TMHs). Among these helices, TMH 6 and 12 align oppositely, lining a drug-binding pocket in the transmembrane region which acts as a pathway for drug efflux. Previously, we demonstrated that specific mutations within TMH 6 and 12 resulted in loss of substrate efflux and altered the transport direction from efflux to uptake for some substrates. This suggested the presence of a regulatory switch that governs the direction of transport. In this study, we sought to elucidate the mechanism of switch region modulation of the uptake function by engineering several mutants via substituting specific residues in TMH 6 and 12. We discovered that the alanine substitution of four residues (V974, L975, V977, and F978) within the upper region of TMH 12, along with three residues (V334, F336, and F343) within TMH 6, was sufficient to convert P-gp from an efflux to an uptake pump. Additional mutagenesis of the residues in the middle region of TMH 12 revealed that the uptake function, like efflux, is reversible. Further studies, including molecular dynamics simulations, revealed that the switch region appears to act during the substrate translocation step. We propose that the switch region in TMH 6 and 12, which modulates the direction of transport by P-gp, provides a novel approach to selectively target P-gp-expressing cancer cells.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 7","pages":"Article 168979"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DOGpred: A Novel Deep Learning Framework for Accurate Identification of Human O-linked Threonine Glycosylation Sites","authors":"Ki Wook Lee ,&nbsp;Nhat Truong Pham ,&nbsp;Hye Jung Min ,&nbsp;Hyun Woo Park ,&nbsp;Ji Won Lee ,&nbsp;Han-En Lo ,&nbsp;Na Young Kwon ,&nbsp;Jimin Seo ,&nbsp;Illia Shaginyan ,&nbsp;Heeje Cho ,&nbsp;Leyi Wei ,&nbsp;Balachandran Manavalan ,&nbsp;Young-Jun Jeon","doi":"10.1016/j.jmb.2025.168977","DOIUrl":"10.1016/j.jmb.2025.168977","url":null,"abstract":"<div><div>O-linked glycosylation is a crucial post-translational modification that regulates protein function and biological processes. Dysregulation of this process is associated with various diseases, underscoring the need to accurately identify O-linked glycosylation sites on proteins. Current experimental methods for identifying O-linked threonine glycosylation (OTG) sites are often complex and costly. Consequently, developing computational tools that predict these sites based on protein features is crucial. Such tools can complement experimental approaches, enhancing our understanding of the role of OTG dysregulation in diseases and uncovering potential therapeutic targets. In this study, we developed DOGpred, a deep learning-based predictor for precisely identifying human OTGs using high-latent feature representations. Initially, we extracted nine different conventional feature descriptors (CFDs) and nine pre-trained protein language model (PLM)-based embeddings. Notably, each feature was encoded as a 2D tensor, capturing both the sequential and inherent feature characteristics. Subsequently, we designed a stacked convolutional neural network (CNN) module to learn spatial feature representations from CFDs and a stacked recurrent neural network (RNN) module to learn temporal feature representations from PLM-based embeddings. These features were integrated using attention-based fusion mechanisms to generate high-level feature representations for final classification. Ablation analysis and independent tests demonstrated that the optimal model (DOGpred), employing a stacked 1D CNN and a stacked attention-based RNN modules with cross-attention feature fusion, achieved the best performance on the training dataset and significantly outperformed machine learning-based single-feature models and state-of-the-art methods on independent datasets. Furthermore, DOGpred is publicly available at <span><span>https://github.com/JeonRPM/DOGpred/</span><svg><path></path></svg></span> for free access and usage.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 6","pages":"Article 168977"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ERNIE-ac4C: A Novel Deep Learning Model for Effectively Predicting N4-acetylcytidine Sites","authors":"Ronglin Lu ,&nbsp;Jianbo Qiao ,&nbsp;Kefei Li ,&nbsp;Yanxi Zhao ,&nbsp;Junru Jin ,&nbsp;Feifei Cui ,&nbsp;Zilong Zhang ,&nbsp;Balachandran Manavalan ,&nbsp;Leyi Wei","doi":"10.1016/j.jmb.2025.168978","DOIUrl":"10.1016/j.jmb.2025.168978","url":null,"abstract":"<div><div>RNA modifications are known to play a critical role in gene regulation and cellular processes. Specifically, N4-acetylcytidine (ac4C) modification has emerged as a significant marker involved in mRNA translation efficiency, stability, and various diseases. Accurate identification of ac4C modification sites is essential for unraveling its functional implications. However, currently available experimental methods suffer from drawbacks such as lengthy detection times, complexity, and high costs, resulting in low efficiency and accuracy in prediction. Although several bioinformatics methods have been proposed and have advanced the prediction of ac4C modification sites, there is still ample room for improvement. In this research, we propose a novel deep learning model, ERNIE-ac4C, which combines the ERNIE-RNA language model and a two-dimensional Convolutional Neural Network (CNN). ERNIE-ac4C utilizes the fusion of sequence features and attention map features to predict ac4C modification sites. ERNIE-ac4C surpasses other state-of-the-art deep learning methods, demonstrating superior accuracy and effectiveness. The availability of the code on GitHub (<span><span>https://github.com/lrlbcxdd/ERNIEac4C.git</span><svg><path></path></svg></span>) and our openness to feedback from the research community contribute to the model’s accessibility and its potential for further advancements. Our study provides valuable insights into ac4C research and enhances our understanding of the functional consequences of RNA modifications.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 6","pages":"Article 168978"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"memerna: Sparse RNA folding including coaxial stacking","authors":"Eliot Courtney ,&nbsp;Amitava Datta ,&nbsp;David H. Mathews ,&nbsp;Max Ward","doi":"10.1016/j.jmb.2024.168819","DOIUrl":"10.1016/j.jmb.2024.168819","url":null,"abstract":"<div><div>Determining RNA secondary structure is a core problem in computational biology. Fast algorithms for predicting secondary structure are fundamental to this task. We describe a modified formulation of the Zuker-Stiegler algorithm with coaxial stacking, a stabilising interaction in which the ends of helices in multi-loops are stacked. In particular, optimal coaxial stacking is computed as part of the dynamic programming state, rather than in an inner loop. We introduce a new notion of sparsity, which we call <em>replaceability</em>. Replaceability is a more general condition and applicable in more places than the <em>triangle inequality</em> that is used by previous sparse folding methods. We also introduce non-monotonic candidate lists as an additional sparsification tool. Existing usages of the triangle inequality for sparsification can be thought of as an application of both replaceability and monotonicity together. The modified recurrences along with replaceability allows sparsification to be applied to coaxial stacking as well, which increases the speed of the algorithm. We implemented this algorithm in software we call <em>memerna</em>, which we show to have the fastest exact (non–heuristic) implementation of RNA folding under the complete Turner 2004 model with coaxial stacking, out of several popular RNA folding tools supporting coaxial stacking. We also introduce a new notation for secondary structure which includes coaxial stacking, terminal mismatches, and dangles (CTDs) information. The memerna package 0.1 release is available at https://github.com/Edgeworth/memerna/tree/release/0.1.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 3","pages":"Article 168819"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142454993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural Dynamics of Rho GTPases","authors":"Yuan Lin ,&nbsp;Yi Zheng","doi":"10.1016/j.jmb.2024.168919","DOIUrl":"10.1016/j.jmb.2024.168919","url":null,"abstract":"<div><div>Rho family GTPases are a part of the Ras superfamily and are signaling hubs for many cellular processes. While the detailed understanding of Ras structure and function has led to tremendous progress in oncogenic Ras-targeted drug discovery, studies of the related Rho GTPases are still catching up as the recurrent cancer-related Rho GTPase mutations have only been discovered in the last decade. Like that of Ras, an in-depth understanding of the structural basis of how Rho GTPases and their mutants behave as key oncogenic drivers benefits the development of clinically effective therapies. Recent studies of structure dynamics in Rho GTPase structure–function relationship have added new twists to the conventional wisdom of Rho GTPase signaling mechanism.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 3","pages":"Article 168919"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142870916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phosphorylation-Dependent Dispersion of the Response Regulator in Bacterial Chemotaxis","authors":"Shirui Ruan ,&nbsp;Rui He ,&nbsp;Yixin Liang,&nbsp;Rongjing Zhang,&nbsp;Junhua Yuan","doi":"10.1016/j.jmb.2024.168920","DOIUrl":"10.1016/j.jmb.2024.168920","url":null,"abstract":"<div><div>Protein phosphorylation is a fundamental cellular regulatory mechanism that governs the activation and deactivation of numerous proteins. In two-component signaling transduction pathways, the phosphorylation of response regulator proteins and their subsequent diffusion play pivotal roles in signal transmission. However, the impact of protein phosphorylation on their dispersion properties remains elusive. In this study, using the response regulator CheY in bacterial chemotaxis as a model, we performed comprehensive measurements of the spatial distributions and diffusion characteristics of CheY and phosphorylated CheY through single-molecule tracking within live cells. We discovered that phosphorylation significantly enhances diffusion and mitigates the constraining influence of the cell membrane on these proteins. Moreover, we observed that ATP-dependent fluctuations also promote protein diffusion and reduce the restraining effect of the cell membrane. These findings highlight important effects of phosphorylation beyond protein activation.</div></div>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":"437 3","pages":"Article 168920"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AllohubPy: Detecting Allosteric Signals Through An Information-theoretic Approach.","authors":"Oriol Gracia Carmona, Jens Kleinjung, Dimitrios Anastasiou, Chris Oostenbrink, Franca Fraternali","doi":"10.1016/j.jmb.2025.168969","DOIUrl":"10.1016/j.jmb.2025.168969","url":null,"abstract":"<p><p>Allosteric regulation is crucial for biological processes like signal transduction, transcriptional regulation, and metabolism, yet the mechanisms and macromolecular properties that govern it are still not well understood. Several methods have been developed over the years to study allosterism through different angles. Among the possible ways to study allosterism, information-theoretic approaches, like AlloHubMat or GSAtools, can be particularly effective due to their use of robust statistics and the possibility to be combined with graph analysis. These methods capture local conformational changes associated with global motions from molecular dynamics simulations through the use of a Structural Alphabet, which simplifies the complexity of the Cartesian space by reducing the dimensionality down to a string of encoded fragments, representing sets of internal coordinates that still capture the overall conformation changes. In this work, we present \"AllohubPy,\" an improved and standardized methodology of AlloHubMat and GSAtools coded in Python. We analyse the performance, limitations and sampling requirements of AllohubPy by using extensive molecular dynamics simulations of model allosteric systems and apply convergence analysis techniques to estimate result reliability. Additionally, we expand the methodology to use different dimensionality reduction Structural Alphabets, such as the 3DI alphabet, and integrate Protein Language Models (PLMs) to refine allosteric hub communication detection by monitoring the detected evolutionary constraints. Overall, AllohubPy expands its preceding methods and simplifies the use and reliability of the method to effectively capture dynamic allosteric motions and residue pathways. AllohubPy is freely available on GitHub (https://github.com/Fraternalilab/AlloHubPy) as a package and as a Jupyter Notebook.</p>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":" ","pages":"168969"},"PeriodicalIF":4.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"UNRES web server: Extensions to nucleic acids, prediction of peptide aggregation, and new types of restrained calculations.","authors":"Rafał Ślusarz, Adam K Sieradzan, Artur Giełdoń, Emilia A Lubecka, Magdalena J Ślusarz, Mateusz Leśniewski, Nguyen Truong Co, Adam Liwo, Cezary Czaplewski","doi":"10.1016/j.jmb.2025.168968","DOIUrl":"https://doi.org/10.1016/j.jmb.2025.168968","url":null,"abstract":"<p><p>The third version of the UNRES web server is described, in which the range of biological macromolecules treated and calculation types has been extended significantly. DNA and RNA molecules have been added to enable the user to run simulations of their folding/hybridization and dynamics. To increase the accuracy of the simulated proteins models, the restraints on secondary structure have been enhanced to include the probabilities of the coil, extended and helical state, which are taken from the PSIPRED or HHpred raw input and the restraints from multiple bioinformatics models have been added. The NMR-data-assisted functionality has been extended to include time-averaged restraints, this feature enabling the user to model multistate and intrinsically-disordered proteins and those with intrinsically-disordered regions. Finally, the prediction of the propensity of peptides to aggregation has been included to enable the user to predict peptide solubility and aggregation, including the character and the structures of the aggregates.</p>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":" ","pages":"168968"},"PeriodicalIF":4.7,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143708058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"rcsb-api: Python Toolkit for Streamlining Access to RCSB Protein Data Bank APIs.","authors":"Dennis W Piehl, Brinda Vallat, Ivana Truong, Habiba Morsy, Rusham Bhatt, Santiago Blaumann, Pratyoy Biswas, Yana Rose, Sebastian Bittrich, Jose M Duarte, Joan Segura, Chunxiao Bi, Douglas Myers-Turnbull, Brian P Hudson, Christine Zardecki, Stephen K Burley","doi":"10.1016/j.jmb.2025.168970","DOIUrl":"10.1016/j.jmb.2025.168970","url":null,"abstract":"<p><p>The Protein Data Bank (PDB) was founded in 1971 as the first open-access digital data resource in biology to serve as the single global archive for three-dimensional (3D) macromolecular structure data. Current PDB holdings exceed 230,000 experimentally determined structures of proteins, nucleic acids, viruses, and macromolecular machines. The RCSB Protein Data Bank RCSB.org research-focused web portal facilitates search, analyses, and visualization of every PDB structure along with more than one million Computed Structure Models from AlphaFold DB and the ModelArchive. It is powered by a set of publicly available Application Programming Interfaces (APIs) that both support RCSB.org users and provide programmatic access to PDB data. Given the breadth and levels of granularity encompassed in this rich data collection, efficiently accessing the information programmatically may be challenging for new users. RCSB PDB has developed a Python software package, rcsb-api, that facilitates easy and efficient use of RCSB PDB APIs within a Python environment. This software tool is designed to streamline access to the extensive corpus of data housed within the PDB, enabling researchers to search, retrieve, and analyze 3D biostructure data seamlessly. Its use will accelerate research in structural biology, molecular biology and biochemistry, drug discovery, and bioinformatics by providing more efficient tools for data integration and analysis. The new toolkit is available on GitHub (github.com/rcsb/py-rcsb-api) and published to the public Python package repository (PyPI) to foster wider usage and support basic and applied research in fundamental biology, biomedicine, and the energy sciences.</p>","PeriodicalId":369,"journal":{"name":"Journal of Molecular Biology","volume":" ","pages":"168970"},"PeriodicalIF":4.7,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143078369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}