Amino Acid Analysis (AAA) is an integral part of analytical biochemistry. In a relatively short time, the variety of AAA methods has evolved dramatically with more methods shifting to the use of mass spectrometry (MS) as a detection method. Another new aspect is miniaturization. However, most importantly, AAA in this day and age should be viewed in the context of Metabolomics as a part of Systems Biology. Amino Acid Analysis: Methods and Protocols presents a broad spectrum of all available methods allowing for readers to choose the method that most suits their particular laboratory set-up and analytical needs. In this volume, a reader can find chapters describing general as well as specific approaches to the sample preparation. A number of chapters describe specific applications of AAA in clinical chemistry as well as in food analysis, microbiology, marine biology, drug metabolism, even archeology. Separate chapters are devoted to the application of AAA for protein quantitation and chiral AAA. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters contain introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and accessible, Amino Acid Analysis: Methods and Protocols provides crucial techniques that can be applied across multiple disciplines by anyone involved in biomedical research or life sciences.

Small proteins with molecular weights of <25 kDa are involved in major biological processes such as ribosome formation, stress adaption and cell cycle control. The study of the low-molecular-weight proteome has identified many central regulators of biology such as cytokines, chemokines, peptide hormones and proteolytic fragments of larger proteins. Due to the unique features of these proteins, the technical challenges are different from those in "common" proteomics. In The Low Molecular Weight Proteome: Methods and Protocols expert researchers from the field provide protocols for analysis of low molecular weight proteins and peptides, protocols for such methods applied in clinical research and an up-to-date review of quantitative protein profiling by labeling. These include methods suitable for both peptide and protein analysis with focus on methods and application that can be used for small protein analysis. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and key tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, The Low Molecular Weight Proteome: Methods and Protocolsis a useful resource for experienced proteomics practitioners as well as an aid to newcomers who wish to become acquainted with the theory and practice of a wide array of methods in analyzing small proteins or peptides.

This volume is comprised of a collection of experimental protocols for common techniques and strategies used to study the biogenesis of b-barrel outer membrane proteins in Gram-negative bacteria. The BAM Complex: Methods and Protocols guides readers through methods on the function of the BAM complex, the roles played by each of the individual components, the expression and purification of the components, crystallization and structure determination of the components, and how the individual Bam components may assemble into a functional complex. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, The BAM Complex: Methods and Protocols will serve as an invaluable reference for those interested in studying the BAM complex.

Long non-coding RNAs (lnc)RNAs have emerged as a new paradigm in epigenetic regulation of the genome. Thousands of lncRNAs have been identified and observed in a wide range of organisms. Unlike mRNA, lncRNA have no protein-coding capacity. So, while their function is not entirely clear, they may serve as key organizers of protein complexes that allow for higher order regulatory events. Discovering these functions has been the result of intense research done of the last few years, and lncRNA research has had several critical developments during that time. This book will consolidate these ideas and models to better examine the most important issues in lncRNA biology. This will include critical studies that have led to the discovery and annotation of lncRNAs in numerous species, and the molecular mechanisms for a few lncRNA that have begun to emerge.

Tryptophan metabolism via kynurenine pathway plays a critical role in both health and a variety of human diseases. This book highlights the known associations between kynurenine pathway and various disease states, as well as examines the current status of drug development and clinical trials of compounds known to alter tryptophan metabolism. The research plays a critical role in molecular targeted therapies directed at altering the kynurenine pathway of tryptophan metabolism. The initial and rate-limiting step of tryptophan metabolism is mediated by one of two enzymes, tryptophan-2,3-dioxygenase (TDO; predominantly in the liver, but also in the brain) and indoleamine-2,3-dioxygenase (IDO; in a host of tissues in response to immune activation). Targeting the enzymes IDO and TDO, as well as other downstream effectors would therefore be likely to generate novel treatment options that would be helpful in a wide variety of clinical settings. This book provides a unique bridge between basic mechanistic understanding of the role of the kynurenine pathway with translational applications and clinical relevance. It will explore the indications that tryptophan metabolism is a potential biomarker of disease activity, can contribute to local and possibly systemic immune suppression in cancer, and is an attractive target for which a variety of inhibitors are readily available.

Cellular adhesion is a fundamental process that influences numerous biological activities such as morphogenesis, cell motility and division, as well as signalling. In addition, adhesion is a process important not only in normal physiology and development, but also in disease states such as tumourigenesis, cardiovascular disease, inflammation and infection. There are a plethora of proteins involved in adhesion-related events with a huge diversity in function. As a result, a wide variety of techniques exist to study adhesion related proteins and processes. In Adhesion Protein Protocols, Third Edition, chapters cover techniques to gain insight into the complex and incompletely understood processes that are involved in cellular adhesion. Written in the successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and easily accessible, Adhesion Protein Protocols, Third Edition will be useful for both those new to the field of adhesion protein research as well as the more experienced scientist.

This detailed volume focuses on methods for the characterization of aggregation processes that lead to the formation of amyloid fibrils and amyloid oligomers which feature in the etiology of a variety of human disorders collectively known as amyloidoses. The scope of the collection includes techniques for visualizing early steps on the amyloid formation pathway, methods for capturing and characterizing oligomeric, potentially toxic, intermediates, strategies for preparing and characterizing mature amyloid fibrils and approaches for understanding templating and transmission of amyloid aggregates. Written in the highly successful Methods in Molecular Biology series format, the chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Protein Amyloid Aggregation: Methods and Protocols serves as an ideal guide for biochemists and biophysicists with an interest in elucidating the mechanisms of protein amyloid formation, as well as chemists, pharmacologists and clinicians with an interest in leveraging an understanding of such mechanisms for the purpose of therapeutic development.

The lipid-rich and otherwise challenging nature of many key tissues complicates many aspects of current research, and applications of the unique nature of lipoproteins and their biological effects has engendered unique and vital methodologies. In Lipoproteins and Cardiovascular Disease: Methods and Protocols, experts in the field present a compendium of advanced and classical molecular biology methods targeted towards lipoprotein, atherosclerosis, and vascular biology research, bringing together in a single volume an updated set of protocols and strategies for methods now driving the most recent advances, along with classical methods that are still widely used. Among the many topics covered in this cutting-edge work, the book delves into crucial techniques such as quantitative real-time PCR, microarrays, RT-PCR laser capture microdissection, and tissue-specific gene overexpression, knockout, and knockdown methodologies, including AAV as a liver-directed gene delivery vehicle. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters include introductions to their respective subjects, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and valuable notes which highlight tips on troubleshooting and avoiding known pitfalls. Comprehensive and easy to use, Lipoproteins and Cardiovascular Disease: Methods and Protocols serves both novices and experts alike as a complete guide for any researcher with an interest in lipoproteins and their significant biological effects.

The basic principle of electron crystallography is to calculate a 3D density map by combining the amplitudes obtained from electron diffraction patterns with the experimental phases calculated from images of two-dimensional crystals of membrane or soluble proteins. This technology is very well developed and has produced a number of atomic models of membrane proteins in a lipid environment. Focused on comprehensive experimental protocols, Electron Crystallography of Soluble and Membrane Proteins: Methods and Protocols covers the entire range of techniques used in electron crystallography, including protein sample preparation, 2D crystallization, and screening in negative stain over electron cryo-microscopy (cryo-EM) and data processing, as well as modeling of conformational changes. Additional chapters provide perspective on past, present, and future challenges as well as complementary methods. Written for the popular Methods in Molecular Biology (TM) series, the work contains the kind of detailed descriptions and implementation advice necessary to ensure successful results. Comprehensive and cutting-edge, Electron Crystallography of Soluble and Membrane Proteins: Methods and Protocols serves laboratories new to the methods as well as state-of-the-art facilities pursuing this exciting area of protein science.

During the past decade as the data on gene sequences and expression patterns rapidly accumulated, cell-free protein synthesis technology has also experienced a revolution, becoming a powerful tool for the preparation of proteins for their functional and structural analysis. In Cell-Free Protein Production: Methods and Protocols, experts in the field contribute detailed techniques, the uses of which expand deep into the studies of biochemistry, molecular biology, and biotechnology. Beginning briefly with basic methods and historical aspects, the book continues with thorough coverage of protein preparation methods, the preparation of proteins that are generally difficult to prepare in their functional forms, applications of the cell-free technologies to protein engineering, as well as some methods that are expected to constitute a part of future technologies. Written in the highly successful Methods in Molecular Biology (TM) series format, the chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Cell-Free Protein Production: Methods and Protocols aims to help researchers continue the growth of the vital exploration of cell-free sciences and technologies in order to better understand the dynamic lives of cells.

How and why certain proteins misfold and how this misfolding is linked to many disease processes has become a well-documented topic of study. Protein Misfolding and Cellular Stress in Disease and Aging: Concepts and Protocols moves beyond the basics to emphasize the molecular effects of protein misfolding at a cellular level, to delineate the impacts and cellular reactions that play a role in pathogenetic mechanisms, and to pinpoint possible manipulations and treatment strategies that can counteract, modify, or delay the consequences of misfolding. The volume begins with several concepts and approaches developed in the recent past including a connection to the research field of aging, where protein misfolding diseases have been equated to premature aging processes, and the book's coverage continues with detailed descriptions of protocols for relevant experimental approaches. Written in the highly successful Methods in Molecular Biology (TM) series format, protocols chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Protein Misfolding and Cellular Stress in Disease and Aging: Concepts and Protocols aims to aid researchers in the field, as well as medical professionals and molecular biologists, in shaping and performing research related to this intriguing and vital subject.

In Fluorescent Protein-Based Biosensors: Methods and Protocols, experts in the field have assembled a series of protocols describing several methods in which fluorescent protein-based reporters can be used to gain unique insights into the regulation of cellular signal transduction. Genetically encodable fluorescent biosensors have allowed researchers to observe biochemical processes within the endogenous cellular environment with unprecedented spatiotemporal resolution. As the number and diversity of available biosensors grows, it is increasingly important to equip researchers with an understanding of the key concepts underlying the design and application of genetically encodable fluorescent biosensors to live cell imaging. Written in the successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and easily accessible, Fluorescent Protein-Based Biosensors: Methods and Protocols promises to be a valuable resource for researchers interested in applying current biosensors to the study of biochemical processes in living cells as well as those interested in developing novel biosensors to visualize other cellular phenomena.

Immunology has made significant progress in the past decade, driven forward by rapidly advancing technology and a renewed interest in the vast realm of innate immunity. The receptors that mediate these functions are at the front lines of both protective and regulative roles of the immune system. In Immune Receptors: Methods and Protocols, expert researchers present a variety of experimental approaches to the characterization of immune receptors and the cell biology that mediates their functions. These include imaging techniques that aim to understand receptor localization and trafficking, techniques to measure receptor-ligand interactions, strategies to identify novel ligands and methods to analyze downstream receptor signaling, as well as strategies for genomic and proteomic characterization of receptor repertoires. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters include introductions to their respective subjects, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Immune Receptors: Methods and Protocols offers technical descriptions and protocols that will be useful both to investigators who are interested in carrying out these procedures and to those who seek a deeper understanding of the bench science that lies behind the immunology literature.

Transcriptional regulation controls the basic processes of life. Its complex, dynamic, and hierarchical networks control the momentary availability of messenger RNAs for protein synthesis. Transcriptional regulation is key to cell division, development, tissue differen- ation, and cancer as discussed in Chapters 1 and 2. We have witnessed rapid, major developments at the intersection of computational biology, experimental technology, and statistics. A decade ago, researches were struggling with notoriously challenging predictions of isolated binding sites from low-throughput experiments. Now we can accurately predict cis-regulatory modules, conserved cl- ters of binding sites (Chapters 13 and 15), partly based on high-throughput ch- matin immunoprecipitation experiments in which tens of millions of DNA segments are sequenced by massively parallel, next-generation sequencers (ChIP-seq, Chapters 9, 10, and 11). These spectacular developments have allowed for the genome-wide mappings of tens of thousands of transcription factor binding sites in yeast, bacteria, mammals, insects, worms, and plants. Please also note the no less spectacular failures in many laboratories around the world.

Beginning from centuries of anecdotal descriptions of cell death, such as those on the development of the midwife toad in 1842 by Carl Vogt, to modern-day investigations of cell death as a biological discipline, it has become accepted that cell death in multicellular organisms is a normal part of life. This book provides a comprehensive view of cell death, from its mechanisms of initiation and execution, to its implication in human disease and therapy. Physiological cell death plays critical roles in almost all aspects of biology, and the book details its roles in lymphocyte homeostasis, neuronal function, metabolism, and the DNA damage response. When physiological cell death goes awry, diseases can arise, and cancer is presented as a central paradigm for the consequences of derangements in the interplay between cell survival and cell death. At the same time, the potential promise of targeted therapies aimed at interdicting cell death machineries are also discussed extensively. The molecular mechanisms that underlie apoptotic cell death are illustrated from the perspectives of both the intrinsic, mitochondrial apoptotic pathway and the extrinsic, death receptor pathway. Key players in these pathways, such as the Bcl2 family proteins, cytochrome c, Apaf-1, caspases, death receptor adapter proteins, and inhibitor of apoptosis proteins, are presented from both functional and structural angles. Until only a few years ago, programmed cell death has been considered essentially synonymous with apoptosis. However, we now know that programmed cell death can also take other forms such as necrosis or necroptosis, and to this end, the mechanisms that underlie programmed necrosis in development and host defense are illustrated. The past twenty plus years have seen an incredible growth of research in cell death, with one breakthrough after another, and the legacy still goes on with constant new surprises and findings. Long live cell death!

This book is intended for scientifc researchers, clinical laboratorians, clinical and translational scientists, and others interested in proteomics and biomarker discovery. Urine is one of the most easily accessible biological samples, and it provides a treasure trove of molecules important in clinical diagnostics. In this book, we review briefly the classical urine tests that are performed in the clinical laboratory and then delve into the state-of-the-art methods for proteomic analysis using urine specimens. The most recent advances are discussed with regard to sample preparation, data analysis, and fnally methods and applications. A multitude of examples are provided including procedural details for the identifcation and characterization of urine biomarkers that hold potential for the diagnosis and treatment of many different disease conditions. The text is arranged so as to read systematically: introduction, sample preparation methods, applications, and data analysis. However, it does not necessarily require the reader to read it from start to fnish. Each chapter is organized such that it can be read individually without requiring knowledge from other chapters. I would like to thank the many individuals who made this book possible. These include the many authors who contributed to each of the individual chapters, the corresponding authors who took responsibility in providing the complete and fnished versions solicited for the peer review process, and the many scientifc reviewers who provided their valuable input and guidance.

Professor Fox's multi-volume Advanced Dairy Chemistry set was first published in four volumes in the early 1980s. A second edition came out in the early 1990s, and an updated third edition was published a decade later. The set is the leading major reference on dairy chemistry, providing in-depth coverage of milk proteins, lipids, and lactose. The editors propose beginning the revision cycle again, with a revised first volume on proteins, to be divided and published separately as Volume 1A - Proteins: Basics Aspects, and Volume 1B - Applied Aspects. Fox and his co-editor, Paul McSweeney, have created an extensively revised the Table of Contents for Volume 1A, which details the novel and updated chapters to be included in this upcoming fourth edition. New contributors include highly regarded dairy scientists and scholars from around the world.

Through the rapid development of proteomics methods and technologies, an enormous amount of data was created, leading to a wide-spread rethinking of strategy design and data interpretation. In Data Mining in Proteomics: From Standards to Applications, experts in the field present these new insights within the proteomics community, taking the historical evolution as well as the most important international standardization projects into account. Along with basic and sophisticated overviews of proteomics technologies, standard data formats, and databases, the volume features chapters on data interpretation strategies including statistics, spectra interpretation, and analysis environments as well as specialized tasks such as data annotation, peak picking, phosphoproteomics, spectrum libraries, LC/MS imaging, and splice isoforms. As a part of the highly successful Methods in Molecular Biology (TM) series, this work provides the kind of detailed description and implementation advice that is crucial for getting optimal results. Authoritative and cutting-edge, Data Mining in Proteomics: From Standards to Applications is a well-balanced compendium for beginners and experts, offering a broad scope of data mining topics but always focusing on the current state-of-the-art and beyond.

This book is devoted to the fascinating superfamily of plant ATP-binding cassette (ABC) transporters and their variety of transported substrates. It highlights their exciting biological functions, covering aspects ranging from cellular detoxification, through development, to symbiosis and defense. Moreover, it also includes a number of chapters that center on ABC transporters from non-Arabidopsis species. ABC proteins are ubiquitous, membrane-intrinsic transporters that catalyze the primary (ATP-dependent) movement of their substrates through biological membranes. Initially identified as an essential aspect of a vacuolar detoxification process, genetic work in the last decade has revealed an unexpectedly diverse variety of ABC transporter substrates, which include not only xenobiotic conjugates, but also heavy metals, lipids, terpenoids, lignols, alkaloids and organic acids. The discovery that members of the ABCB and ABCG family are involved in the movement of phytohormones has further sparked their exploration and provided a new understanding of the whole family. Accordingly, the trafficking, regulation and structure-function of ABCB-type auxin transporters are especially emphasized in this book.

Protein-protein interactions (PPIs) are strongly predictive of functional relationships among proteins in virtually all processes that take place in the living cell. Therefore, the comprehensive exploration of interactome networks is one of the major goals in systems biology. The aim of Two Hybrid Technologies: Methods and Protocols is to provide a compendium of state-of-the art protocols for the investigation of binary PPIs with the classical yeast two-hybrid (Y2H) approach, Y2H variants and other in vivo methods for PPI mapping. Divided into two convenient sections, the first gives a survey of protocols that are currently employed for Y2H high-throughput screens by different expert labs in the field. Rather than detailing the principles of screening, which have been described previously, the focus is on different implementations of Y2H interactome mapping. The second section of the book considers innovative PPI detection methods that have the potential to emerge as alternative high-throughput methodologies. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters contain introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and accessible, Two Hybrid Technologies: Methods and Protocols supplies researchers with a comprehensive toolbox for the identification of biologically relevant protein interactions.

It is increasingly clear that signal transduction is a highly organized and integrated process. Divided into two convenient sections, Signal Transduction Protocols, Third Edition focuses on experimental approaches to better understand the complexity of signal transduction. Introductory chapters provide perspective on several of the challenges involved in signal transduction research and offer guidance on selecting the best approaches to various types of questions. The individual chapters provide detailed experimental protocols covering various topics, from the effects of ligand binding on receptor conformation and effector coupling, to moving inside the cell in order to capture the spatial and temporal characteristics of signaling events. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters contain introductions to their respective topics, lists of the necessary materials and reagents, step-by step, readily reproducible laboratory protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and accessible, Signal Transduction Protocols serves as an ideal guide to scientists of all backgrounds and is a valuable resource for future progress in the field of signal transduction research.

Protein modifications and changes made to them, as well as the quantities of expressed proteins, can define the various functional stages of the cell. Accordingly, perturbations can lead to various diseases and disorders. As a result, it has become paramount to be able to detect and monitor post-translational modifications and to measure the abundance of proteins within the cell with extreme sensitivity. While protein identification is an almost routine requirement nowadays, reliable techniques for quantifying unmodified proteins (including those that escape detection under standard conditions, such as protein isoforms and membrane proteins) is not routine. Quantitative Methods in Proteomics gives a detailed survey of topics and methods on the principles underlying modern protein analysis, from statistical issues when planning proteomics experiments, to gel-based and mass spectrometry-based applications. The quantification of post-translational modifications is also addressed, followed by the "hot" topics of software and data analysis, as well as various overview chapters which provide a comprehensive overview of existing methods in quantitative proteomics. Written in the successful Methods in Molecular Biology (TM) series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and easily accessible, Quantitative Methods in Proteomics serves as a comprehensive and competent overview of the important and still growing field of quantitative proteomics.

Remarkably, while G protein-coupled receptors (GPCRs) are highly prevalent in animals and yeast, very few candidate GPCRs have been identified in plants. In G Protein-Coupled Receptor Signaling in Plants: Methods and Protocols, experts in the field describe techniques used in the study of small GTPases and related proteins. Beginning with a chapter on bioinformatics approaches for GPCR discovery, this detailed volume continues with chapters on heterotrimeric G protein subunits, Rab-GTPases, as well as lipid modifications, including myristoylation, acylation, and prenylation. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Practical and dependable, G Protein-Coupled Receptor Signaling in Plants: Methods and Protocols aims to aid further studies into the roles of small GTPases which will help elucidate numerous key processes in plants.

Knowledge about protein tertiary structure can guide experiments, assist in the understanding of structure-function relationships, and aid the design of new therapeutics for disease. Homology modeling is an in silico method that predicts the tertiary structure of an amino acid sequence based on a homologous experimentally determined structure. In, Homology Modelling: Methods and Protocols experts in the field describe each homology modeling step from first principles, provide case studies for challenging modeling targets and describe methods for the prediction of how other molecules such as drugs can interact with the protein. Written in the highly successful Methods in Molecular Biology (TM) series format, the chapters include the kind of detailed description and implementation advice that is crucial for getting optimal results in the laboratory. Thorough and intuitive, Homology Modelling: Methods and Protocols guides scientists in the available homology modeling methods.

This book provides a molecular view of membrane transport by means of numerous biochemical and biophysical techniques. The rapidly growing numbers of atomic structures of transporters in different conformations and the constant progress in bioinformatics have recently added deeper insights. The unifying mechanism of energized solute transport across membranes is assumed to consist of the conformational cycling of a carrier protein to provide access to substrate binding sites from either side of a cellular membrane. Due to the central role of active membrane transport there is considerable interest in deciphering the principles of one of the most fundamental processes in nature: the alternating access mechanism. This book brings together particularly significant structure-function studies on a variety of carrier systems from different transporter families: Glutamate symporters, LeuT-like fold transporters, MFS transporters and SMR (RND) exporters, as well as ABC-type importers. The selected examples impressively demonstrate how the combination of functional analysis, crystallography, investigation of dynamics and computational studies has made it possible to create a conclusive picture or more precisely, "a molecular movie". Although we are still far from a complete molecular description of the alternating access mechanism, remarkable progress has been made from static snapshots towards membrane transport dynamics.