121 research outputs found
InterPro in 2022.
The InterPro database (https://www.ebi.ac.uk/interpro/) provides an integrative classification of protein sequences into families, and identifies functionally important domains and conserved sites. Here, we report recent developments with InterPro (version 90.0) and its associated software, including updates to data content and to the website. These developments extend and enrich the information provided by InterPro, and provide a more user friendly access to the data. Additionally, we have worked on adding Pfam website features to the InterPro website, as the Pfam website will be retired in late 2022. We also show that InterPro's sequence coverage has kept pace with the growth of UniProtKB. Moreover, we report the development of a card game as a method of engaging the non-scientific community. Finally, we discuss the benefits and challenges brought by the use of artificial intelligence for protein structure prediction
Genome Desertification in Eutherians: Can Gene Deserts Explain the Uneven Distribution of Genes in Placental Mammalian Genomes?
The evolution of genome size as well as structure and organization of genomes belongs among the key questions of genome biology. Here we show, based on a comparative analysis of 30 genomes, that there is generally a tight correlation between the number of genes per chromosome and the length of the respective chromosome in eukaryotic genomes. The surprising exceptions to this pattern are placental mammalian genomes. We identify the number and, more importantly, the uneven distribution of gene deserts among chromosomes, i.e., long (>500Â kb) stretches of DNA that do not encode for genes, as the main contributing factor for the observed anomaly of eutherian genomes. Gene-rich placental mammalian chromosomes have smaller proportions of gene deserts and vice versa. We show that the uneven distribution of gene deserts is a derived character state of eutherians. The functional and evolutionary significance of this particular feature of eutherian genomes remains to be explained
Structural Analysis of the Essential Resuscitation Promoting Factor YeaZ Suggests a Mechanism of Nucleotide Regulation through Dimer Reorganization
Extent: 8p.Background: The yeaZ gene product forms part of the conserved network YjeE/YeaZ/YgjD essential for the survival of many Gram-negative eubacteria. Among other as yet unidentified roles, YeaZ functions as a resuscitation promoting factor required for survival and resuscitation of cells in a viable but non-culturable (VBNC) state. Methodology/Principal Findings: In order to investigate in detail the structure/function relationship of this family of proteins we have performed X-ray crystallographic studies of Vibrio parahaemolyticus YeaZ. The YeaZ structure showed that it has a classic actin-like nucleotide-binding fold. Comparisons of this crystal structure to that of available homologues from E. coli, T. maritima and S. typhimurium revealed two distinctly different modes of dimer formation. In one form, prevalent in the absence of nucleotide, the putative nucleotide-binding site is incomplete, lacking a binding pocket for a nucleotide base. In the second form, residues from the second subunit complete the nucleotide-binding site. This suggests that the two dimer architectures observed in the crystal structures correspond to a free and a nucleotide-bound form of YeaZ. A multiple sequence alignment of YeaZ proteins from different bacteria allowed us to identify a large conserved hydrophobic patch on the protein surface that becomes exposed upon nucleotide-driven dimer re-arrangement. We hypothesize that the transition between two dimer architectures represents the transition between the âonâ and âoffâ states of YeaZ. The effect of this transition is to alternately expose and bury a docking site for the partner protein YgjD. Conclusions/Significance: This paper provides the first structural insight into the putative mechanism of nucleotide regulation of YeaZ through dimer reorganization. Our analysis suggests that nucleotide binding to YeaZ may act as a regulator or switch that changes YeaZ shape, allowing it to switch partners between YjeE and YgjD.Inci Aydin, Yumiko Saijo-Hamano, Keiichi Namba, Connor Thomas and Anna Roujeinikov
Resection of the primary tumour versus no resection prior to systemic therapy in patients with colon cancer and synchronous unresectable metastases (UICC stage IV): SYNCHRONOUS - a randomised controlled multicentre trial (ISRCTN30964555)
<p>Abstract</p> <p>Background</p> <p>Currently, it remains unclear, if patients with colon cancer and synchronous unresectable metastases who present without severe symptoms should undergo resection of the primary tumour prior to systemic chemotherapy. Resection of the primary tumour may be associated with significant morbidity and delays the beginning of chemotherapy. However, it may prevent local symptoms and may, moreover, prolong survival as has been demonstrated in patients with metastatic renal cell carcinoma. It is the aim of the present randomised controlled trial to evaluate the efficacy of primary tumour resection prior to systemic chemotherapy to prolong survival in patients with newly diagnosed colon cancer who are not amenable to curative therapy.</p> <p>Methods/design</p> <p>The SYNCHRONOUS trial is a multicentre, randomised, controlled, superiority trial with a two-group parallel design. Colon cancer patients with synchronous unresectable metastases are eligible for inclusion. Exclusion criteria are primary tumour-related symptoms, inability to tolerate surgery and/or systemic chemotherapy and history of another primary cancer. Resection of the primary tumour as well as systemic chemotherapy is provided according to the standards of the participating institution. The primary endpoint is overall survival that is assessed with a minimum follow-up of 36 months. Furthermore, it is the objective of the trial to assess the safety of both treatment strategies as well as quality of life.</p> <p>Discussion</p> <p>The SYNCHRONOUS trial is a multicentre, randomised, controlled trial to assess the efficacy and safety of primary tumour resection before beginning of systemic chemotherapy in patients with metastatic colon cancer not amenable to curative therapy.</p> <p>Trial registration</p> <p><a href="http://www.controlled-trials.com/ISRCTN30964555">ISRCTN30964555</a></p
Unique Properties of Eukaryote-Type Actin and Profilin Horizontally Transferred to Cyanobacteria
A eukaryote-type actin and its binding protein profilin encoded on a genomic island in the cyanobacterium Microcystis aeruginosa PCC 7806 co-localize to form a hollow, spherical enclosure occupying a considerable intracellular space as shown by in vivo fluorescence microscopy. Biochemical and biophysical characterization reveals key differences between these proteins and their eukaryotic homologs. Small-angle X-ray scattering shows that the actin assembles into elongated, filamentous polymers which can be visualized microscopically with fluorescent phalloidin. Whereas rabbit actin forms thin cylindrical filaments about 100 Âľm in length, cyanobacterial actin polymers resemble a ribbon, arrest polymerization at 5-10 Âľm and tend to form irregular multi-strand assemblies. While eukaryotic profilin is a specific actin monomer binding protein, cyanobacterial profilin shows the unprecedented property of decorating actin filaments. Electron micrographs show that cyanobacterial profilin stimulates actin filament bundling and stabilizes their lateral alignment into heteropolymeric sheets from which the observed hollow enclosure may be formed. We hypothesize that adaptation to the confined space of a bacterial cell devoid of binding proteins usually regulating actin polymerization in eukaryotes has driven the co-evolution of cyanobacterial actin and profilin, giving rise to an intracellular entity
Novel roles of the chemorepellent axon guidance molecule RGMa in cell migration and adhesion
The repulsive guidance molecule A (RGMa) is a contact-mediated axon guidance molecule that has significant roles in central nervous system (CNS) development. Here we have examined whether RGMa has novel roles in cell migration and cell adhesion outside the nervous system. RGMa was found to stimulate cell migration from Xenopus animal cap explants in a neogenin-dependent and BMP-independent manner. RGMa also stimulated the adhesion of Xenopus animal cap cells, and this adhesion was dependent on neogenin and independent of calcium. To begin to functionally characterize the role of specific domains in RGMa, we assessed the migratory and adhesive activities of deletion mutants. RGMa lacking the partial von Willebrand factor type D (vWF) domain preferentially perturbed cell adhesion, while mutants lacking the RGD motif affected cell migration. We also revealed that manipulating the levels of RGMa in vivo caused major migration defects during Xenopus gastrulation. We have revealed here novel roles of RGMa in cell migration and adhesion and demonstrated that perturbations to the homeostasis of RGMa expression can severely disrupt major morphogenetic events. These results have implications for understanding the role of RGMa in both health and disease
Suppression of Estrogen Receptor Transcriptional Activity by Connective Tissue Growth Factor
Secreted growth factors have been shown to stimulate the transcriptional activity of estrogen receptors (ER) that are responsible for many biological processes. However, whether these growth factors physically interact with ER remains unclear. Here, we show for the first time that connective tissue growth factor (CTGF) physically and functionally associates with ER. CTGF interacted with ER both in vitro and in vivo. CTGF interacted with ER DNA-binding domain. ER interaction region in CTGF was mapped to the thrombospondin type I repeat, a cell attachment motif. Overexpression of CTGF inhibited ER transcriptional activity as well as the expression of estrogen-responsive genes, including pS2 and cathepsin D. Reduction of endogenous CTGF with CTGF small interfering RNA enhanced ER transcriptional activity. The interaction between CTGF and ER is required for the repression of estrogen-responsive transcription by CTGF. Moreover, CTGF reduced ER protein expression, whereas the CTGF mutant that did not repress ER transcriptional activity also did not alter ER protein levels. The results suggested the transcriptional regulation of estrogen signaling through interaction between CTGF and ER, and thus may provide a novel mechanism by which cross-talk between secreted growth factor and ER signaling pathways occurs
Genomic variation landscape of the human gut microbiome
While large-scale efforts have rapidly advanced the understanding and practical impact of human genomic variation, the latter is largely unexplored in the human microbiome. We therefore developed a framework for metagenomic variation analysis and applied it to 252 fecal metagenomes of 207 individuals from Europe and North America. Using 7.4 billion reads aligned to 101 reference species, we detected 10.3 million single nucleotide polymorphisms (SNPs), 107,991 short indels, and 1,051 structural variants. The average ratio of non-synonymous to synonymous polymorphism rates of 0.11 was more variable between gut microbial species than across human hosts. Subjects sampled at varying time intervals exhibited individuality and temporal stability of SNP variation patterns, despite considerable composition changes of their gut microbiota. This implies that individual-specific strains are not easily replaced and that an individual might have a unique metagenomic genotype, which may be exploitable for personalized diet or drug intake
Contact dermatitis and other skin conditions in instrumental musicians
BACKGROUND: The skin is important in the positioning and playing of a musical instrument. During practicing and performing there is a permanent more or less intense contact between the instrument and the musician's skin. Apart from aggravation of predisposed skin diseases (e.g., atopic eczema or psoriasis) due to music-making, specific dermatologic conditions may develop that are directly caused by playing a musical instrument. METHODS: To perform a systematic review on instrument-related skin diseases in musicians we searched the PubMed database without time limits. Furthermore we studied the online bibliography "Occupational diseases of performing artist. A performing arts medicine bibliography. October, 2003" and checked references of all selected articles for relevant papers. RESULTS: The most prevalent skin disorders of instrumental musicians, in particular string instrumentalists (e.g., violinists, cellists, guitarists), woodwind players (e.g., flautists, clarinetists), and brass instrumentalists (e.g., trumpeters), include a variety of allergic contact sensitizations (e.g., colophony, nickel, and exotic woods) and irritant (physical-chemical noxae) skin conditions whose clinical presentation and localization are usually specific for the instrument used (e.g., "fiddler's neck", "cellist's chest", "guitar nipple", "flautist's chin"). Apart from common callosities and "occupational marks" (e.g., "Garrod's pads") more or less severe skin injuries may occur in musical instrumentalists, in particular acute and chronic wounds including their complications. Skin infections such as herpes labialis seem to be a more common skin problem in woodwind and brass instrumentalists. CONCLUSIONS: Skin conditions may be a significant problem not only in professional instrumentalists, but also in musicians of all ages and ability. Although not life threatening they may lead to impaired performance and occupational hazard. Unfortunately, epidemiological investigations have exclusively been performed on orchestra musicians, though the prevalence of instrument-related skin conditions in other musician groups (e.g., jazz and rock musicians) is also of interest. The practicing clinician should be aware of the special dermatologic problems unique to the musical instrumentalist. Moreover awareness among musicians needs to be raised, as proper technique and conditioning may help to prevent affection of performance and occupational impairment
Assessing the functional coherence of modules found in multiple-evidence networks from Arabidopsis
<p>Abstract</p> <p>Background</p> <p>Combining multiple evidence-types from different information sources has the potential to reveal new relationships in biological systems. The integrated information can be represented as a relationship network, and clustering the network can suggest possible functional modules. The value of such modules for gaining insight into the underlying biological processes depends on their functional coherence. The challenges that we wish to address are to define and quantify the functional coherence of modules in relationship networks, so that they can be used to infer function of as yet unannotated proteins, to discover previously unknown roles of proteins in diseases as well as for better understanding of the regulation and interrelationship between different elements of complex biological systems.</p> <p>Results</p> <p>We have defined the functional coherence of modules with respect to the Gene Ontology (GO) by considering two complementary aspects: (i) the fragmentation of the GO functional categories into the different modules and (ii) the most representative functions of the modules. We have proposed a set of metrics to evaluate these two aspects and demonstrated their utility in <it>Arabidopsis thaliana</it>. We selected 2355 proteins for which experimentally established protein-protein interaction (PPI) data were available. From these we have constructed five relationship networks, four based on single types of data: PPI, co-expression, co-occurrence of protein names in scientific literature abstracts and sequence similarity and a fifth one combining these four evidence types. The ability of these networks to suggest biologically meaningful grouping of proteins was explored by applying Markov clustering and then by measuring the functional coherence of the clusters.</p> <p>Conclusions</p> <p>Relationship networks integrating multiple evidence-types are biologically informative and allow more proteins to be assigned to a putative functional module. Using additional evidence types concentrates the functional annotations in a smaller number of modules without unduly compromising their consistency. These results indicate that integration of more data sources improves the ability to uncover functional association between proteins, both by allowing more proteins to be linked and producing a network where modular structure more closely reflects the hierarchy in the gene ontology.</p
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