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PubMed2002

Myocardial proteome analysis reveals reduced NOS inhibition and enhanced glycolytic capacity in areas of low local blood flow.

In the heart, in situ local myocardial blood flow (MBF) varies greater than 10-fold between individual areas and displays a spatially heterogeneous pattern. To analyze its molecular basis, we analyzed protein expression of low and high flow samples (300 mg, <50% or >150% of mean MBF, each n=30) of six beagle dogs by 2-D polyacrylamide gel electrophoresis (380 +/- 78 spots/gel). In low flow samples, dimethylarginine dimethylaminohydrolase (DDAH1) was increased greatly (+377%, compared with high flow samples). This increase resulted in a 75% reduction of asymmetric dimethylarginine (ADMA), the potent endogenous inhibitor of NO synthase, whereas eNOS showed no difference. Low flow samples exhibited enhanced expression of GAPDH (+89%) and phosphoglycerate kinase (+100%), whereas hydroxyacyl-CoA dehydrogenase, electron transfer flavoprotein, myoglobin, and desmin were decreased. Assessing local MBF on different days within 2 weeks revealed a high degree of MBF stability (r2 > 0.79). Thus, stable differences in local MBF are associated with significant differences in local gene and protein expression. In low flow areas, the increased DDAH1 reduces ADMA concentration and NOS inhibition, which strongly suggests enhanced NO formation. Low flow areas are also characterized by a higher glycolytic and a lower fatty acid oxidation capacity. Both the shift in substrate utilization and the rise in NO may contribute to the known lower oxygen consumption in these areas.

Amidohydrolases↗

PubMed2002

Functional genomics of the social amoebae, Dictyostelium discoideum.

Dictyostelium discoideum is one of the simplest organisms to form a multicellular structure, and it offers several advantages as a model. In order to understand the genetic basis of the multicellular development, a comprehensive analysis of cDNAs is being performed. To date, about 75,000 ESTs have been collected at different stages of development. They have been assembled into about 6,400 independent sequences that represent 70-80% of all of the expected genes in D. discoideum. The results are available on the Internet. In addition to structural analyses, functional analyses of the temporal and spatial expression patterns and gene targeting are being carried out. Furthermore, there are plans to combine the information that is obtained from the cDNA, Genome, and Proteome Projects, as well as the published results, into an integrated database, DictyBase.

Animals↗

PubMed2026

Human IL-34 Deficiency Primes Microglia Toward Alzheimer's Disease-Associated States.

BACKGROUND: Genome-wide association studies (GWAS), with independent replication in large European consortia, have identified a common nonsense variant in IL-34 (Y213X) as a genetic risk factor for late-onset Alzheimer's disease (AD). However, the biological consequences of this IL-34 mutation in humans, its prevalence in the population, and the mechanisms by which IL-34-Y213X alters microglial homeostasis, cerebrospinal fluid (CSF) proteomic networks, and amyloid pathology remain poorly understood. METHODS: We combined human genetics, cerebrospinal fluid (CSF) and serum proteomics, transcriptomics, large-scale phenome-wide association analyses, and preclinical experimental models to define the impact of human IL-34 deficiency. IL-34 concentrations were first quantified in CSF and serum from deeply phenotyped AD cohorts stratified by the common IL-34-Y213X nonsense variant. IL-34 levels and IL-34-Y213X status were then integrated with unbiased CSF proteomic networks and AD biomarkers. Transcriptomic profiling of purified microglia from IL-34 knockout mice was performed to assess disease-associated microglial programs. Using APP/PS1 mice lacking IL-34, we examined the effects of IL-34 deficiency on microglial survival, tiling, and plaque encapsulation. Finally, we performed postmortem analyses of temporal cortex from AD patients carrying IL-34-Y213X to assess microglial density, spatial organization, and plaque-associated responses. FINDINGS: IL-34-Y213X was a strong, dose-dependent loss-of-function (LOF) allele that reduced IL-34 levels by up to 2.5 standard deviations in CSF and serum and was common in multiple populations. IL-34 deficiency reshaped CSF proteomic networks, downregulating axon guidance and microglial support modules while upregulating inflammatory and extracellular matrix signatures, and showed pleiotropic associations with neurological, inflammatory, and metabolic traits. Transcriptomic analysis of sorted microglia from healthy 9-month-old IL-34KO compare to wild-type mice revealed a profound pro-inflammatory and disease-associated microglial transcriptional program enriched for disease-associated microglia (DAM) signatures, inflammatory pathways, and AD risk genes including APOE, CLU, and CASS4. In APP/PS1 mice, genetic IL-34 deletion selectively depleted homeostatic gray-matter microglia, disrupted microglial tiling, and impaired plaque encapsulation, resulting in altered amyloid structure and enhancing neuritic injury. Concordantly, AD patients homozygous for IL-34-Y213X displayed markedly reduced cortical microglial density and increased microglial spatial dispersion, indicating a breakdown of the microglial network organization in the human brain. INTERPRETATION: A common human IL-34 LOF variant creates a naturally occurring model of IL-34 deficiency that links microglial survival, CSF network signatures, and amyloid pathology in both mice and humans. Importantly, IL-34 deficiency alone is sufficient to induce inflammatory, AD-associated microglial states beyond simply reducing microglial number. These findings identify IL-34/CSF1R signaling as a critical determinant of microglial resilience and a potential upstream pathway linking human genetic variation to AD susceptibility, highlighting IL-34-dependent pathways as promising targets for disease modification. FUNDING: This work was supported by grants from the Spanish Ministerio de Ciencia, Innovación y Universidades/FEDER/UE (PID2024-157400OB-I00) and FORTALECE program (FORT23/00008; Instituto de Salud Carlos III, Spain) to RRL and JLV, ISCIII of Spain co-financed by FEDER funds (European Union) through grants PI24/00308 (JV) and CIBERNED collaborative grant 2022/01 to JV, PID2023-147125OB-I00 and CEX2023-001386-S (Severo Ochoa Programme) to SMTBC. A.R. is supported by STAR Award. University of Texas System. Tx, United States, The South Texas ADRC. National Institute of Aging. National Institutes of Health. USA. (P30AG066546), the Keith M. Orme and Pat Vigeon Orme Endowed Chair in Alzheimer's and Neurodegenerative Diseases (2024-2025) and Patricia Ruth Frederick Distinguished Chair for Precision Therapeutics in Alzheimer's and Neurodegenerative Diseases (2025-2028). AR is also supported by the Agency for Innovation and Entrepreneurship (VLAIO) grant N° PR067/21 for the HARPONE project and the ADAPTED project the EU/EFPIA Innovative Medicines Initiative Joint Undertaking Grant N° 115975 and CIBERNED (ISCIII).

Journal Article↗

PubMed2025

Spatial Mapping and Interactome Profiling of m6A-Modified R-Loops via Chemically Inducible Split-APEX2 Proximity Labeling.

m6A-Modified R-loops (m6A-R-loops) play crucial roles in epigenetic regulation and genome stability, yet resolving their spatial distribution and protein interactomes in live cells remains challenging. To address this, we developed m6A-R-loop proximity labeling (m6A-RLPL), a chemically inducible split-APEX2 proximity labeling technology integrating dual-target recognition using the RNA-DNA hybrid binding domain of RNase H1 for R-loop targeting and m6A reader protein's YTH domain for m6A recognition, coupled with an abscisic acid (ABA)-inducible dimerization system for signal amplification. This technology revealed host m6A-R-loops enriched with nucleoli under normal conditions. When applied to herpes simplex virus (HSV) infection, it further demonstrated viral m6A-R-loops undergoing dramatic accumulation within phase-separated granules in replication compartments during late-stage infection. Proximity proteomics identified ZC3H4 and CCDC124 as essential regulators maintaining these structures, which serve as transcription sites for HSV late genes, with disruption selectively impairing viral transcription. m6A-RLPL establishes a generalizable approach for spatially resolved profiling of m6A-R-loop interactomes and organizational dynamics in living systems.

Humans↗

PubMed2026

Next-Generation Disease Profiling by Integrating Histopathology with Spatial Multi-Omics Data.

The field of pathology has experienced several transformative changes in recent years with the advent of digital pathology and spatial multi-omics. These technologies have enhanced every aspect of pathology practice, from streamlining daily workflows to generating high-fidelity multi-omics data that provide pathologists with novel tools to refine disease profiling and clinical diagnosis. Each layer of multimodal data (genomic, metabolomic, proteomic, or transcriptomic) has uncovered a distinct facet of disease pathologies, and combined with machine learning/artificial intelligence-based data analysis and pattern recognition models, has provided holistic understanding of regulatory mechanisms underpinning them. However, high-dimensional data have far exceeded the volume, scale, and complexity of immunostaining methods implemented by pathologists and, thus, have generated significant challenges related to deconvolution, interpretation, and clinical translation. Furthermore, these multimodal studies have predominantly relied on computational methods to process data and extract disease-relevant insights, thus raising questions around relevance or role of a pathologist in this new era of multi-omics. This review will provide a perspective on the evolving fields of molecular histopathology and spatial -omics, leveraging them to approach disease profiling, and redefining the role of a pathologist during this process.

Humans↗

PubMed2005

Systems biology in the cell nucleus.

The mammalian nucleus is arguably the most complex cellular organelle. It houses the vast majority of an organism's genetic material and is the site of all major genome regulatory processes. Reductionist approaches have been spectacularly successful at dissecting at the molecular level many of the key processes that occur within the nucleus, particularly gene expression. At the same time, the limitations of analyzing single nuclear processes in spatial and temporal isolation and the validity of generalizing observations of single gene loci are becoming evident. The next level of understanding of genome function is to integrate our knowledge of their sequences and the molecular mechanisms involved in nuclear processes with our insights into the spatial and temporal organization of the nucleus and to elucidate the interplay between protein and gene networks in regulatory circuits. To do so, catalogues of genomes and proteomes as well as a precise understanding of the behavior of molecules in living cells are required. Converging technological developments in genomics, proteomics, dynamics and computation are now leading towards such an integrated biological understanding of genome biology and nuclear function.

Animals↗

PubMedDate not supplied

Application of mass spectrometry in proteomics.

Mass spectrometry has arguably become the core technology in proteomics. The application of mass spectrometry based techniques for the qualitative and quantitative analysis of global proteome samples derived from complex mixtures has had a big impact in the understanding of cellular function. Here, we give a brief introduction to principles of mass spectrometry and instrumentation currently used in proteomics experiments. In addition, recent developments in the application of mass spectrometry in proteomics are summarised. Strategies allowing high-throughput identification of proteins from highly complex mixtures include accurate mass measurement of peptides derived from total proteome digests and multidimensional peptide separations coupled with mass spectrometry. Mass spectrometric analysis of intact proteins permits the characterisation of protein isoforms. Recent developments in stable isotope labelling techniques and chemical tagging allow the mass spectrometry based differential display and quantitation of proteins, and newly established affinity procedures enable the targeted characterisation of post-translationally modified proteins. Finally, advances in mass spectrometric imaging allow the gathering of specific information on the local molecular composition, relative abundance and spatial distribution of peptides and proteins in thin tissue sections.

Affinity Labels↗

PubMed2002

Region-specific alternative splicing in the nervous system: implications for regulation by the RNA-binding protein NAPOR.

Alternative RNA splicing generates extensive proteomic diversity in the nervous system, yet few neural-specific RNA binding proteins have been implicated in splicing control. Here we show that the biochemical properties and spatial expression of mouse neuroblastoma apoptosis-related RNA-binding protein (NAPOR; also called NAPOR-1) are consistent with its roles in the regulation of the exon 5 and exon 21 splicing events of the N-methyl-D-aspartate (NMDA) receptor R1 transcript. NAPOR, which is closely related to CUG binding protein 2 (CUG-BP2), promotes exon 21 and represses exon 5 splicing in functional coexpression assays. These NMDA mRNA isoforms are distributed, in vivo, in a region-specific manner in rat brain, such that high levels of exon 21 selection and exon 5 skipping coincide with high NAPOR mRNA expression in the forebrain. Within the forebrain, this spatial correspondence is most striking in the visual cortex. In contrast, low NAPOR expression coincides with the reciprocal pattern of alternative splicing in the hindbrain. Complementary experiments demonstrate a tissue-specific distribution of NAPOR, CUG-BP, and other highly related proteins within the nervous system as assayed by probing forebrain and hindbrain nuclear extracts with monoclonal antibody, mAb 3B1. Thus, NAPOR may be one of a group of closely related proteins involved in splicing regulation within the brain. An intronic RNA element responsible for the silencing of exon 21 splicing is identified by mutational analysis and shown to bind directly to recombinant NAPOR protein, suggesting a model in which exon 21 selection is positively regulated by an antirepression mechanism of action.

Alternative Splicing↗

PubMed2001

Genetic engineering of neural function in transgenic rodents: towards a comprehensive strategy?

As mammalian genome projects move towards completion, the attention of molecular neuroscientists is currently moving away from gene identification towards both cell-specific gene expression patterns (neuronal transcriptions) and protein expression/interactions (neuronal proteomics). In the long term, attention will increasingly be directed towards experimental interventions which are able to question neuronal function in a sophisticated manner that is cognisant of both transcriptomic and proteomic organization. Central to this effort will be the application of a new generation of transgenic approaches which are now evolving towards an appropriate level of molecular, temporal and spatial resolution. In this review, we summarize recent developments in transgenesis, and show how they have been applied in the principal model species for neuroscience, namely rats and mice. Current concepts of transgene design are also considered together with an overview of new genetically-encoded tools including both cellular indicators such as fluorescent activity reporters, and cellular regulators such as dominant negative signalling factors. Application of these tools in a whole animal context can be used to question both basic concepts of brain function, and also current concepts of underlying dysfuction in neurological diseases.

Animals↗

PubMed2026

Antibody-Based Proximity Labeling Reveals Bait-Proximal Proteomes in Paraffin-Embedded and Snap-Frozen Tissue Samples.

Proximity-based labeling approaches have proven highly valuable for uncovering protein-protein interactions, yet their application to primary patient material remains challenging. Here, we present a workflow enabling the use of the antibody-based ProtA-Turbo proximity labeling system in both formalin-fixed paraffin-embedded (FFPE) and snap-frozen tissue specimens. Our method efficiently directs biotinylation to diverse antibody baits across tissues of different origins. Downstream mass spectrometry-based proteomics analyses demonstrate the specificity of the method by profiling the proximal proteome of H3K27ac-marked chromatin, the nuclear lamina-associated protein EMD, and the Ser2-phosphorylated POLR2A subunit of RNA polymerase II. Using this method, we identified cell-type-specific factors and transcriptional regulators in salivary gland carcinoma, healthy testis, and testicular cancer tissue sections. The ability to detect disease-associated complexes directly within their native, spatially resolved cellular context using ProtA-Turbo can provide new insights into the molecular basis of human disease and may reveal novel, potentially actionable factors with translational relevance.

Humans↗

PubMed2006

Computational methods for comparison of large genomic and proteomic datasets reveal protein markers of metastatic cancer.

Large-scale genomic and proteomic analysis has provided a wealth of information on biologically relevant systems, and the ability to analyze this information is crucial to uncovering important biological relationships. However, it has proven difficult to compare large datasets from different sources due to different gene and protein identifiers assigned by individual laboratories and database systems. Here, we describe the design of a fully automated blast program (BlastPro) that facilitates rapid comparison of large protein-protein, nucleotide--nucleotide, or nucleotide--protein datasets from numerous, independent studies. Using this system, we compared several published genomic and proteomic databases for proteins that are upregulated in highly motile, metastatic tumor cells. Analysis of five independent studies comprised of greater than 1 x 10(6) genomic sequences and greater than 1,000 proteins revealed that the cytoskeletal-associated protein alpha-actinin is increased at both the mRNA and protein level in metastatic breast, prostate, and skin cancer cells. Interestingly, spatial analysis of alpha-actinin expression revealed that it is amplified 8-fold in the leading pseudopodium compared to the cell body compartment of migrating cells. These findings indicate that amplification of alpha-actinin and its localization to the leading pseudopodium are potential biomarkers of cancer progression to a more metastatic phenotype. Together, our results demonstrate that the BlastPro system can be used to compare large genomic and proteomic datasets to reveal important biological relationships including those associated with cancer progression.

Actinin↗

PubMed2002

The propagator (retarded Green function) formalism as a new calculation method to predict the time evolution of bands in capillary electrophoresis and microchannels.

Capillary electrophoresis (CE) and microchannel (MC) techniques are important tools in chemical and biological sciences, mainly in the study of genomes, transcriptomes, proteomes, metabolomes, and organic as well as inorganic ions. The speed of DNA sequencing increased significantly during the last decade with the use of capillary electrophoresis (CE). The time evolution of the bands' spatial profile inside capillaries and channels is of paramount importance, since the main goal of these techniques is to maximize resolution (the ratio between the spacing of the peaks and their mean standard deviations). In the present work, the propagator (retarded Green function) formalism is applied to solve a few problems which are typical for CE and MC. We also apply this mathematical method to the problem of velocity gradients along the capillary, i.e., the time evolution of the bands is analyzed when they enter regions where they migrate with different velocities.

Diffusion↗

PubMed2026

Addressing lignin composition and content via Arabidopsis arogenate dehydratase knockout and over-expression genotypes.

Following the down-selection of 14 Arabidopsis thaliana arogenate dehydratase (ADT) knockout and over-expression (OE) genotypes, the most highly contrasting quadruple knockout adt3/4/5/6 and ADT OE genotypes were subjected to proteomics, metabolomics, and scanning electron microscopy (SEM) analyses as needed, with results compared to Columbia wild-type (WT). The basal adt3/4/5/6 stem cross-sections, ∼70% lignin content reduced, exhibited buckled vessel cell walls and partially detached xylary fibers, in contrast to WT and ADT4m/5 m OE genotypes that did not. Anatomical defects primarily resulted from guaiacyl lignin level reductions in vessels with concomitant increased stem syringyl:guaiacyl (S/G) ratios. Phenylpropanoid and various upstream shikimate-chorismate pathway enzyme abundances, as well as specific monolignol oxidases (laccases/peroxidases), generally increased in adt3/4/5/6 at different stem and rosette leaf growth/development stages, relative to WT. Opposite effects were largely observed with the ADT5m OE genotype. By contrast, flavonoid and glucosinolate pathway enzyme amounts varied. Such enzyme abundance increases were overall unproductive as adt3/4/5/6 was unable to restore WT, ADT4 OE, ADT5 OE, ADT5m OE, and ADT4m/5 m OE secondary metabolite (lignin, phenylpropanoid, lignan, flavonoid, phenolic acid, and glucosinolate) levels. Conversely, ADT OE genotypes did not significantly increase programmed lignin levels or alter S/G compositions. In sum, proteomics analyses of adt3/4/5/6 and adt5 'perceived' that lignin and low molecular weight secondary metabolite amounts were not at 'programmed' levels as for WT and ADT OE genotypes but observed increases in relevant pathway protein abundances were futile. Notably though, proteomics analyses did not lead to predicting that lignin and associated biochemical pathways would have reduced metabolite levels, relative to WT and ADT OE genotypes. Genotype adt3/4/5/6, possibly the highest lignin level reduced genotype reported, did not utilize other phenolics to compensate. By contrast, the differential temporal and spatial deposition of cell wall oxidases again indicate the exquisite control over lignin deposition, and our lack of knowledge of precise lignin structure and assembly in subcellular regions of the lignified cell walls.

Lignin↗

PubMed2003

Peptidomics: A new approach to affinity protein microarrays.

Protein microarrays for diagnostic and proteomic analyses are being developed using a number of different techniques for each of the steps required including immobilisation methods, assay and detection systems. This is extremely different to the development of DNA microarrays which is now a well established technology that has demonstrated the capabilities of transcriptomics to deliver validated differential transcripts. As mRNA and protein levels do not always correlate, protein microarrays would seem to be an obvious successor to DNA arrays. Unlike nucleic acids, however, protein targets are typically nonhomogeneous in physicochemical properties and affinity capture agents are often poorly characterised making the experiments difficult to perfect and reproduce. Moreover, running multiple affinity assays in parallel (multiplexing) is compromised by the heterogeneity of antibody affinities to their protein targets. In the peptidomic approach presented here the assayed mixture of proteins is enzymatically digested prior to affinity capture to form a mixture of short peptides that are more similar in their physicochemical properties than intact proteins. These peptides can be predicted by in silico digestion of individual proteins, e.g. from protein databases allowing design of nonhomologous reagents for the screening of affinity agent libraries. The use of mass spectrometry (e.g. matrix-assisted laser desorption/ionization-time of flight mass spectrometry) for a direct confirmation of the identity of the species captured, provides a further advantage compared to the more usual method of detection in which fluorescently labelled captured species are scanned to give a spatially resolved image of the array.

Peptides↗

PubMed2004

Proteomic analysis of molecular response to oxidative stress by the green alga Haematococcus pluvialis (Chlorophyceae).

Rapidly growing, green motile flagellates of Haematococcus pluvialis can transform into enlarged red resting cysts (aplanospores) under oxidative stress conditions. However, it is not known what initial molecular defense mechanisms occur in response to oxidative stress, and may ultimately lead to cellular transformation. In this study, global-expression profiling of cellular proteins in response to stress was analyzed by two-dimensional gel electrophoresis, image analysis, and peptide mass fingerprinting. Oxidative stress was induced in cultures of green flagellates by addition of acetate and Fe2+, and exposure to excess light intensity. Overall, 70 proteins were identified with altered expression patterns following stress induction. Some key proteins involved in photosynthesis and nitrogen assimilation were down-regulated, whereas some mitochondrial respiratory proteins were transiently up-regulated after the onset of stress. Most of the identified proteins, particularly those from the families of superoxide dismutase, catalase, and peroxidase, were transiently up-regulated, but reverted to down-regulation during the 6 days of stress. On the other hand, cellular accumulation of the antioxidant astaxanthin occurred well after initiation of oxidative stress and reached its maximum cellular level after six or more days of stress. It appears that the early stress response involves multiple enzymatic defense processes that play a critical role upon onset of stress and also during the early transition of green vegetative cells to red cysts. As cyst development continues, the intensive, enzyme-mediated initial responses were largely replaced in mature red cysts by accumulation of the molecular antioxidant astaxanthin. This study provides the first direct evidence for a massive, and concerted up-regulation of multiple antioxidative defense mechanisms, both spatially and temporarily, to protect H. pluvialis cells against oxidative stress.

Chlorophyta↗

PubMedDate not supplied

Gene and protein profiling of the response of MA-10 Leydig tumor cells to human chorionic gonadotropin.

Activation of the steroidogenic machinery by peptide hormones involves a number of steps for transmitting signals from the plasma membrane to mitochondria in a spatially and temporally coordinated manner. Although key proteins mediating the hormonal signal have been identified, recent data suggest that the pathway might involve more complex protein-protein and protein-lipid interactions. Genomic and proteomic methods of analysis, namely the Affymetrix Murine Genome U74A v2 GeneChip and the BD PowerBlot Western Array, were used to identify human chorionic gonadotropin (hCG)-induced changes in mRNA and protein of MA-10 Leydig tumor cells that parallel the increase seen in progesterone synthesis. To analyze the massive amount of data that was generated, a comprehensive protein information matrix summarizing the features of each gene or protein, including its known properties, as well as annotations derived by homology-based functional inference, was developed. Of the genes examined by Affymetrix array, approximately 79 were differentially expressed and of gene products examined by PowerBlot, 9 were differentially expressed (above twofold). Changes in the expression of selected transcripts of interest were confirmed using real-time quantitative polymerase chain reaction and immunoblot analyses. Collectively, these results indicate that hormonal regulation of steroidogenesis is a complex phenomenon, involving proteins that participate in various known and novel pathways, which are implicated in transmitting signals from the plasma membrane to mitochondria and nucleus.

Blotting, Western↗

PubMed2004

Manipulation of alternative splicing by a newly developed inhibitor of Clks.

The regulation of splice site usage provides a versatile mechanism for controlling gene expression and for the generation of proteome diversity, playing an essential role in many biological processes. The importance of alternative splicing is further illustrated by the increasing number of human diseases that have been attributed to mis-splicing events. Appropriate spatial and temporal generation of splicing variants demands that alternative splicing be subjected to extensive regulation, similar to transcriptional control. The Clk (Cdc2-like kinase) family has been implicated in splicing control and consists of at least four members. Through extensive screening of a chemical library, we found that a benzothiazole compound, TG003, had a potent inhibitory effect on the activity of Clk1/Sty. TG003 inhibited SF2/ASF-dependent splicing of beta-globin pre-mRNA in vitro by suppression of Clk-mediated phosphorylation. This drug also suppressed serine/arginine-rich protein phosphorylation, dissociation of nuclear speckles, and Clk1/Sty-dependent alternative splicing in mammalian cells. Consistently, administration of TG003 rescued the embryonic defects induced by excessive Clk activity in Xenopus. Thus, TG003, a novel inhibitor of Clk family will be a valuable tool to dissect the regulatory mechanisms involving serine/arginine-rich protein phosphorylation signaling pathways in vivo, and may be applicable for the therapeutic manipulation of abnormal splicing.

Alternative Splicing↗

PubMed2004

Nuclear microenvironments support assembly and organization of the transcriptional regulatory machinery for cell proliferation and differentiation.

The temporal and spatial organization of transcriptional regulatory machinery provides microenvironments within the nucleus where threshold concentrations of genes and cognate factors facilitate functional interactions. Conventional biochemical, molecular, and in vivo genetic approaches, together with high throughput genomic and proteomic analysis are rapidly expanding our database of regulatory macromolecules and signaling pathways that are requisite for control of genes that govern proliferation and differentiation. There is accruing insight into the architectural organization of regulatory machinery for gene expression that suggests signatures for biological control. Localized scaffolding of regulatory macromolecules at strategic promoter sites and focal compartmentalization of genes, transcripts, and regulatory factors within intranuclear microenvironments provides an infrastructure for combinatorial control of transcription that is operative within the three dimensional context of nuclear architecture.

Cell Cycle↗