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1.
J Behav Med ; 2024 Apr 26.
Article En | MEDLINE | ID: mdl-38671287

Children in rural communities consume more energy-dense foods relative to their urban peers. Identifying effective interventions for improving energy intake patterns are needed to address these geographic disparities. The primary aim of this study was to harness the benefits of physical activity on children's executive functioning to see if these improvements lead to acute changes in eating behaviors. In a randomized crossover design, 91 preadolescent (8-10y; M age = 9.48 ± 0.85; 50.5% female; 85.7% White, 9.9% Multiracial, 9.9% Hispanic) children (86% rural) completed a 20-minute physical activity condition (moderate intensity walking) and time-matched sedentary condition (reading and/or coloring) ~ 14 days apart. Immediately following each condition, participants completed a behavioral inhibition task and then eating behaviors (total energy intake, relative energy intake, snack intake) were measured during a multi-array buffet test meal. After adjusting for period and order effects, body fat (measured via DXA), and depressive symptoms, participants experienced significant small improvements in their behavioral inhibition following the physical activity versus sedentary condition (p = 0.04, Hedge's g = 0.198). Eating behaviors did not vary by condition, nor did improvements in behavioral inhibition function as a mediator (ps > 0.09). Thus, in preadolescent children, small improvements in behavioral inhibition from physical activity do not produce acute improvements in energy intake. Additional research is needed to clarify whether the duration and/or intensity of physical activity sessions would produce different results in this age group, and whether intervention approaches and corresponding mechanisms of change vary by individual factors, like age and degree of food cue responsivity.

2.
J Surg Case Rep ; 2024(2): rjae076, 2024 Feb.
Article En | MEDLINE | ID: mdl-38389511

Basaloid squamous cell carcinoma (BSCC) is a rare and aggressive variant of squamous cell carcinoma. It is commonly seen in the oropharynx and strongly associated with p16-expressivity and high-risk human papilloma virus (HPV). We report the first case of primary cutaneous p16-positive BSCC in an elderly woman, with a background of chronic inverse psoriasis of the natal cleft. P16-expressivity is a common surrogate marker for oncogenic HPV16, routinely tested for oropharyngeal/anogenital squamous cell carcinoma. This is not routinely done for primary cutaneous disease. Pilonidal disease is uncommon in the elderly population, and malignant transformation is rarer still. Surgical resection is considered the mainstay of treatment for primary cutaneous BSCC, however due to this patient's broad distribution of cutaneous field change and p16-expressivity, she was effectively treated with primary radiotherapy. This is a unique case of malignant transformation of pilonidal disease in an atypical demographic, with a rare/aggressive disease variant.

3.
Behav Modif ; 47(6): 1423-1454, 2023 11.
Article En | MEDLINE | ID: mdl-31375029

There has been growing interest in using statistical methods to analyze data and estimate effect size indices from studies that use single-case designs (SCDs), as a complement to traditional visual inspection methods. The validity of a statistical method rests on whether its assumptions are plausible representations of the process by which the data were collected, yet there is evidence that some assumptions-particularly regarding normality of error distributions-may be inappropriate for single-case data. To develop more appropriate modeling assumptions and statistical methods, researchers must attend to the features of real SCD data. In this study, we examine several features of SCDs with behavioral outcome measures in order to inform development of statistical methods. Drawing on a corpus of over 300 studies, including approximately 1,800 cases, from seven systematic reviews that cover a range of interventions and outcome constructs, we report the distribution of study designs, distribution of outcome measurement procedures, and features of baseline outcome data distributions for the most common types of measurements used in single-case research. We discuss implications for the development of more realistic assumptions regarding outcome distributions in SCD studies, as well as the design of Monte Carlo simulation studies evaluating the performance of statistical analysis techniques for SCD data.


Outcome Assessment, Health Care , Research Design , Humans , Computer Simulation , Outcome Assessment, Health Care/methods
5.
Multivariate Behav Res ; 53(4): 574-593, 2018.
Article En | MEDLINE | ID: mdl-29757002

Single-case designs are a class of repeated measures experiments used to evaluate the effects of interventions for small or specialized populations, such as individuals with low-incidence disabilities. There has been growing interest in systematic reviews and syntheses of evidence from single-case designs, but there remains a need to further develop appropriate statistical models and effect sizes for data from the designs. We propose a novel model for single-case data that exhibit nonlinear time trends created by an intervention that produces gradual effects, which build up and dissipate over time. The model expresses a structural relationship between a pattern of treatment assignment and an outcome variable, making it appropriate for both treatment reversal and multiple baseline designs. It is formulated as a generalized linear model so that it can be applied to outcomes measured as frequency counts or proportions, both of which are commonly used in single-case research, while providing readily interpretable effect size estimates such as log response ratios or log odds ratios. We demonstrate the gradual effects model by applying it to data from a single-case study and examine the performance of proposed estimation methods in a Monte Carlo simulation of frequency count data.


Models, Statistical , Computer Simulation , Data Interpretation, Statistical , Humans , Meta-Analysis as Topic , Monte Carlo Method , Nonlinear Dynamics
6.
ACS Synth Biol ; 6(12): 2273-2280, 2017 12 15.
Article En | MEDLINE | ID: mdl-28877583

This paper presents Leaf LIMS, a flexible laboratory information management system (LIMS) designed to address the complexity of synthetic biology workflows. At the project's inception there was a lack of a LIMS designed specifically to address synthetic biology processes, with most systems focused on either next generation sequencing or biobanks and clinical sample handling. Leaf LIMS implements integrated project, item, and laboratory stock tracking, offering complete sample and construct genealogy, materials and lot tracking, and modular assay data capture. Hence, it enables highly configurable task-based workflows and supports data capture from project inception to completion. As such, in addition to it supporting synthetic biology it is ideal for many laboratory environments with multiple projects and users. The system is deployed as a web application through Docker and is provided under a permissive MIT license. It is freely available for download at https://leaflims.github.io .


Database Management Systems , Databases, Factual , Synthetic Biology , Synthetic Biology/instrumentation , Synthetic Biology/methods
7.
Genome Res ; 27(5): 778-786, 2017 05.
Article En | MEDLINE | ID: mdl-28159771

Long-read sequencing can overcome the weaknesses of short reads in the assembly of eukaryotic genomes; however, at present additional scaffolding is needed to achieve chromosome-level assemblies. We generated Pacific Biosciences (PacBio) long-read data of the genomes of three relatives of the model plant Arabidopsis thaliana and assembled all three genomes into only a few hundred contigs. To improve the contiguities of these assemblies, we generated BioNano Genomics optical mapping and Dovetail Genomics chromosome conformation capture data for genome scaffolding. Despite their technical differences, optical mapping and chromosome conformation capture performed similarly and doubled N50 values. After improving both integration methods, assembly contiguity reached chromosome-arm-levels. We rigorously assessed the quality of contigs and scaffolds using Illumina mate-pair libraries and genetic map information. This showed that PacBio assemblies have high sequence accuracy but can contain several misassemblies, which join unlinked regions of the genome. Most, but not all, of these misjoints were removed during the integration of the optical mapping and chromosome conformation capture data. Even though none of the centromeres were fully assembled, the scaffolds revealed large parts of some centromeric regions, even including some of the heterochromatic regions, which are not present in gold standard reference sequences.


Chromosomes, Plant/chemistry , Contig Mapping/methods , Genome, Plant , Genomics/methods , Software , Arabidopsis/genetics , Chromosomes, Plant/genetics , Contig Mapping/standards , Genomics/standards
8.
Am J Hum Genet ; 99(6): 1292-1304, 2016 Dec 01.
Article En | MEDLINE | ID: mdl-27866708

Uncombable hair syndrome (UHS), also known as "spun glass hair syndrome," "pili trianguli et canaliculi," or "cheveux incoiffables" is a rare anomaly of the hair shaft that occurs in children and improves with age. UHS is characterized by dry, frizzy, spangly, and often fair hair that is resistant to being combed flat. Until now, both simplex and familial UHS-affected case subjects with autosomal-dominant as well as -recessive inheritance have been reported. However, none of these case subjects were linked to a molecular genetic cause. Here, we report the identification of UHS-causative mutations located in the three genes PADI3 (peptidylarginine deiminase 3), TGM3 (transglutaminase 3), and TCHH (trichohyalin) in a total of 11 children. All of these individuals carry homozygous or compound heterozygous mutations in one of these three genes, indicating an autosomal-recessive inheritance pattern in the majority of UHS case subjects. The two enzymes PADI3 and TGM3, responsible for posttranslational protein modifications, and their target structural protein TCHH are all involved in hair shaft formation. Elucidation of the molecular outcomes of the disease-causing mutations by cell culture experiments and tridimensional protein models demonstrated clear differences in the structural organization and activity of mutant and wild-type proteins. Scanning electron microscopy observations revealed morphological alterations in hair coat of Padi3 knockout mice. All together, these findings elucidate the molecular genetic causes of UHS and shed light on its pathophysiology and hair physiology in general.


Antigens/genetics , Hair Diseases/genetics , Hair/growth & development , Hydrolases/genetics , Intermediate Filament Proteins/genetics , Mutation , Transglutaminases/genetics , Adolescent , Animals , Base Sequence , Cell Line , Codon, Nonsense , Female , Hair/abnormalities , Hair/anatomy & histology , Hair/metabolism , Humans , Hydrolases/deficiency , Hydrolases/metabolism , Male , Mice , Mice, Knockout , Models, Molecular , Mutation, Missense/genetics , Protein Conformation , Protein-Arginine Deiminase Type 3 , Protein-Arginine Deiminases , Transglutaminases/deficiency , Transglutaminases/metabolism , Vibrissae/abnormalities
9.
BMC Biol ; 14(1): 84, 2016 10 03.
Article En | MEDLINE | ID: mdl-27716181

BACKGROUND: In February 2016, a new fungal disease was spotted in wheat fields across eight districts in Bangladesh. The epidemic spread to an estimated 15,000 hectares, about 16 % of the cultivated wheat area in Bangladesh, with yield losses reaching up to 100 %. Within weeks of the onset of the epidemic, we performed transcriptome sequencing of symptomatic leaf samples collected directly from Bangladeshi fields. RESULTS: Reinoculation of seedlings with strains isolated from infected wheat grains showed wheat blast symptoms on leaves of wheat but not rice. Our phylogenomic and population genomic analyses revealed that the wheat blast outbreak in Bangladesh was most likely caused by a wheat-infecting South American lineage of the blast fungus Magnaporthe oryzae. CONCLUSION: Our findings suggest that genomic surveillance can be rapidly applied to monitor plant disease outbreaks and provide valuable information regarding the identity and origin of the infectious agent.


Magnaporthe/pathogenicity , Plant Diseases/microbiology , Triticum/microbiology , Bangladesh , Gene Expression Regulation, Plant , Plant Diseases/genetics , Triticum/genetics
10.
BMC Cancer ; 16: 629, 2016 08 12.
Article En | MEDLINE | ID: mdl-27519597

BACKGROUND: Melanotic neuroectodermal tumor of infancy (MNTI) is exceptionally rare and occurs predominantly in the head and neck (92.8 % cases). The patient reported here is only the eighth case of MNTI presenting in an extremity, and the first reported in the fibula. CASE PRESENTATION: A 2-month-old female presented with a mass arising in the fibula. Exhaustive genomic, transcriptomic, epigenetic and pathological characterization was performed on the excised primary tumor and a derived cell line. Whole-exome analysis of genomic DNA from both the tumor and blood indicated no somatic, non-synonymous coding mutations within the tumor, but a heterozygous, unique germline, loss of function mutation in CDKN2A (p16(INK4A), D74A). SNP-array CGH on DNA samples revealed the tumor to be euploid, with no detectable gene copy number variants. Multiple chromosomal translocations were identified by RNA-Seq, and fusion genes included RPLP1-C19MC, potentially deregulating the C19MC cluster, an imprinted locus containing microRNA genes reactivated by gene fusion in embryonal tumors with multilayered rosettes. Since the presumed cell of origin of MNTI is from the neural crest, we also compared gene expression with a dataset from human neural crest cells and identified 185 genes with significantly different expression. Consistent with the melanotic phenotype of the tumor, elevated expression of tyrosinase was observed. Other highly expressed genes encoded muscle proteins and modulators of the extracellular matrix. A derived MNTI cell line was sensitive to inhibitors of lysine demethylase, but not to compounds targeting other epigenetic regulators. CONCLUSIONS: In the absence of somatic copy number variations or mutations, the fully transformed phenotype of the MNTI may have arisen in infancy because of the combined effects of a germline CDKN2A mutation, tumor promoting somatic fusion genes and epigenetic deregulation. Very little is known about the etiology of MNTI and this report advances knowledge of these rare tumors by providing the first comprehensive genomic, transcriptomic and epigenetic characterization of a case.


Bone Neoplasms/genetics , Cyclin-Dependent Kinase Inhibitor p18/genetics , Fibula/pathology , Germ-Line Mutation , Neuroectodermal Tumor, Melanotic/genetics , Oncogene Proteins, Fusion/genetics , Cyclin-Dependent Kinase Inhibitor p16 , Female , Gene Expression Regulation, Neoplastic , Humans , Infant , Phosphoproteins/genetics , Ribosomal Proteins/genetics , Sequence Analysis, DNA , Sequence Analysis, RNA
11.
Hum Mutat ; 37(2): 170-4, 2016 Feb.
Article En | MEDLINE | ID: mdl-26593283

Deafblindness is part of several genetic disorders. We investigated a consanguineous Egyptian family with two siblings affected by congenital hearing loss and retinal degeneration, initially diagnosed as Usher syndrome type 1. At teenage, severe enamel dysplasia, developmental delay, and microcephaly became apparent. Genome-wide homozygosity mapping and whole-exome sequencing detected a homozygous missense mutation, c.1238G>T (p.Gly413Val), affecting a highly conserved residue of peroxisomal biogenesis factor 6, PEX6. Biochemical profiling of the siblings revealed abnormal and borderline plasma phytanic acid concentration, and cerebral imaging revealed white matter disease in both. We show that Pex6 localizes to the apical extensions of secretory ameloblasts and differentiated odontoblasts at early stages of dentin synthesis in mice, and to cilia of retinal photoreceptor cells. We propose PEX6, and possibly other peroxisomal genes, as candidate for the rare cooccurrence of deafblindness and enamel dysplasia. Our study for the first time links peroxisome biogenesis disorders to retinal ciliopathies.


Adenosine Triphosphatases/genetics , Deaf-Blind Disorders/genetics , Dental Enamel Hypoplasia/genetics , Microcephaly/genetics , Mutation, Missense , Retinal Degeneration/genetics , ATPases Associated with Diverse Cellular Activities , Adenosine Triphosphatases/metabolism , Ameloblasts/metabolism , Ameloblasts/pathology , Amino Acid Sequence , Animals , Child , Cilia/metabolism , Cilia/pathology , Consanguinity , Deaf-Blind Disorders/metabolism , Deaf-Blind Disorders/pathology , Dental Enamel Hypoplasia/metabolism , Dental Enamel Hypoplasia/pathology , Female , Gene Expression , Homozygote , Humans , Male , Mice , Microcephaly/metabolism , Microcephaly/pathology , Molecular Sequence Data , Odontoblasts/metabolism , Odontoblasts/pathology , Pedigree , Photoreceptor Cells, Vertebrate/metabolism , Photoreceptor Cells, Vertebrate/pathology , Retinal Degeneration/metabolism , Retinal Degeneration/pathology , Siblings , White Matter/metabolism , White Matter/pathology , Young Adult
12.
Multivariate Behav Res ; 50(3): 365-80, 2015.
Article En | MEDLINE | ID: mdl-26610035

Partial interval recording (PIR) is a procedure for collecting measurements during direct observation of behavior. It is used in several areas of educational and psychological research, particularly in connection with single-case research. Measurements collected using partial interval recording suffer from construct invalidity because they are not readily interpretable in terms of the underlying characteristics of the behavior. Using an alternating renewal process model for the behavior under observation, we demonstrate that ignoring the construct invalidity of PIR data can produce misleading inferences, such as inferring that an intervention reduces the prevalence of an undesirable behavior when in fact it has the opposite effect. We then propose four different methods for analyzing PIR summary measurements, each of which can be used to draw inferences about interpretable behavioral parameters. We demonstrate the methods by applying them to data from two single-case studies of problem behavior.


Behavioral Research , Models, Statistical , Computer Simulation , Humans , Time Factors
13.
BMC Genomics ; 16: 910, 2015 Nov 07.
Article En | MEDLINE | ID: mdl-26547235

BACKGROUND: We describe the pioneering experience of a Spanish family pursuing the goal of understanding their own personal genetic data to the fullest possible extent using Direct to Consumer (DTC) tests. With full informed consent from the Corpas family, all genotype, exome and metagenome data from members of this family, are publicly available under a public domain Creative Commons 0 (CC0) license waiver. All scientists or companies analysing these data ("the Corpasome") were invited to return results to the family. METHODS: We released 5 genotypes, 4 exomes, 1 metagenome from the Corpas family via a blog and figshare under a public domain license, inviting scientists to join the crowdsourcing efforts to analyse the genomes in return for coauthorship or acknowldgement in derived papers. Resulting analysis data were compiled via social media and direct email. RESULTS: Here we present the results of our investigations, combining the crowdsourced contributions and our own efforts. Four companies offering annotations for genomic variants were applied to four family exomes: BIOBASE, Ingenuity, Diploid, and GeneTalk. Starting from a common VCF file and after selecting for significant results from company reports, we find no overlap among described annotations. We additionally report on a gut microbiome analysis of a member of the Corpas family. CONCLUSIONS: This study presents an analysis of a diverse set of tools and methods offered by four DTC companies. The striking discordance of the results mirrors previous findings with respect to DTC analysis of SNP chip data, and highlights the difficulties of using DTC data for preventive medical care. To our knowledge, the data and analysis results from our crowdsourced study represent the most comprehensive exome and analysis for a family quartet using solely DTC data generation to date.


Crowdsourcing , Family , Genetic Testing , Genomics , Crowdsourcing/methods , Exome , Female , Gene Frequency , Genetic Testing/methods , Genomics/methods , Genotype , Humans , Male , Metagenome , Pedigree , Phenotype , Polymorphism, Single Nucleotide , Precision Medicine/methods , Quantitative Trait, Heritable , Spain
14.
Orphanet J Rare Dis ; 9: 12, 2014 Jan 23.
Article En | MEDLINE | ID: mdl-24456803

BACKGROUND: WWOX, encoding WW domain-containing oxidoreductase, spans FRA16D, the second most common chromosomal fragile site frequently altered in cancers. It is therefore considered a tumor suppressor gene, but its direct implication in cancerogenesis remains controversial. METHODS AND RESULTS: By whole-exome sequencing, we identified a homozygous WWOX nonsense mutation, p.Arg54*, in a girl from a consanguineous family with a severe syndrome of growth retardation, microcephaly, epileptic seizures, retinopathy and early death, a phenotype highly similar to the abormalities reported in lde/lde rats with a spontaneous functional null mutation of Wwox. As in rats, no tumors were observed in the patient or heterozygous mutation carriers. CONCLUSIONS: Our finding, a homozygous loss-of-function germline mutation in WWOX in a patient with a lethal autosomal recessive syndrome, supports an alternative role of WWOX and indicates its importance for human viability.


Epilepsy/genetics , Microcephaly/genetics , Humans , Infant , Mutation , Oxidoreductases/genetics , Retinal Degeneration/genetics , Tumor Suppressor Proteins/genetics , WW Domain-Containing Oxidoreductase
15.
Eur J Hum Genet ; 22(2): 286-8, 2014 Feb.
Article En | MEDLINE | ID: mdl-23838597

Although many genes have been identified for the autosomal recessive cerebellar ataxias (ARCAs), several patients are unlinked to the respective loci, suggesting further genetic heterogeneity. We combined homozygosity mapping and exome sequencing in a consanguineous Egyptian family with congenital ARCA, mental retardation and pyramidal signs. A homozygous 5-bp deletion in SPTBN2, the gene whose in-frame mutations cause autosomal dominant spinocerebellar ataxia type 5, was shown to segregate with ataxia in the family. Our findings are compatible with the concept of truncating SPTBN2 mutations acting recessively, which is supported by disease expression in homozygous, but not heterozygous, knockout mice, ataxia in Beagle dogs with a homozygous frameshift mutation and, very recently, a homozygous SPTBN2 nonsense mutation underlying infantile ataxia and psychomotor delay in a human family. As there was no evidence for mutations in 23 additional consanguineous families, SPTBN2-related ARCA is probably rare.


Spectrin/genetics , Spinocerebellar Ataxias/diagnosis , Alleles , Base Sequence , Child , Codon, Nonsense , Consanguinity , DNA Mutational Analysis , Developmental Disabilities/diagnosis , Developmental Disabilities/genetics , Female , Homozygote , Humans , Lod Score , Male , Pedigree , Spinocerebellar Ataxias/genetics
16.
Mol Nutr Food Res ; 57(12): 2195-205, 2013 Dec.
Article En | MEDLINE | ID: mdl-23934683

SCOPE: Intake of the essential micronutrient selenium (Se) has health implications. This work addressed whether some effects of Se on gene expression are exerted through microRNAs (miRNA). METHODS AND RESULTS: Human colon adenocarcinoma cells (Caco-2) were grown in Se-deficient or Se-adequate medium for 72 h. RNA was extracted and subjected to analysis of 737 miRNA using microarray technology. One hundred and forty-five miRNA were found to be expressed in Caco-2 cells. Twelve miRNA showed altered expression after Se depletion: miR-625, miR-492, miR-373*, miR-22, miR-532-5p, miR-106b, miR-30b, miR-185, miR-203, miR1308, miR-28-5p, miR-10b. These changes were validated by quantitative real-time PCR (RT-qPCR). Transcriptomic analysis showed that Se depletion altered expression of 50 genes including selenoproteins GPX1, SELW, GPX3, SEPN1, SELK, SEPSH2 and GPX4. Pathway analysis identified arachidonic acid metabolism, glutathione metabolism, oxidative stress, positive acute phase response proteins and respiration of mitochondria as Se-sensitive pathways. Bioinformatic analysis identified 13 transcripts as targets for the Se-sensitive miRNA; three were predicted to be recognised by miR-185. Silencing of miR-185 increased GPX2 and SEPSH2 expression. CONCLUSIONS: We propose that miR-185 plays a role in up-regulation of GPX2 and SEPHS2 expression. In the case of SEPHS2 this may contribute to maintaining selenoprotein synthesis. The data indicate that micronutrient supply can regulate the cell miRNA expression profile.


Glutathione Peroxidase/genetics , MicroRNAs/genetics , Phosphotransferases/genetics , Selenium/pharmacology , Caco-2 Cells/drug effects , Gene Expression Regulation/drug effects , Gene Knockdown Techniques , Humans , Intestines/cytology , Intestines/drug effects , Intestines/physiology , Up-Regulation
17.
Age (Dordr) ; 35(5): 1835-49, 2013 Oct.
Article En | MEDLINE | ID: mdl-23229445

Changes in DNA methylation across the life course may contribute to the ageing process. We hypothesised that some effects of dietary restriction to extend lifespan and/or mitigate against features of ageing result from changes in DNA methylation, so we determined if genes that respond to dietary restriction also show age-related changes in DNA methylation. In support of our hypothesis, the intersection of lists of genes compiled from published sources that (1) were differentially expressed in response to dietary restriction and (2) showed altered methylation with increased age was greater than expected. We also hypothesised that some effects of Sirt1, which may play a pivotal role in beneficial effects of dietary restriction, are mediated through DNA methylation. We thus measured effects of Sirt1 overexpression and knockdown in a human cell line on DNA methylation and expression of a panel of eight genes that respond to dietary restriction and show altered methylation with age. Six genes were affected at the level of DNA methylation, and for six expressions were affected. In further support of our hypothesis, we observed by DNA microarray analysis that genes showing differential expression in response to Sirt1 knockdown were over-represented in the complied list of genes that respond to dietary restriction. The findings reveal that Sirt1 has effects on DNA methylation across the genome and affects, in particular, the expression of genes that respond to dietary restriction. Sirt1-mediated effects on DNA methylation and, consequently, gene expression may thus be one of the mechanisms underlying the response to dietary restriction.


Aging/genetics , DNA Methylation/drug effects , DNA/genetics , Diet, Reducing/methods , Gene Expression Regulation/drug effects , Sirtuin 1/genetics , Animals , Cell Line , Humans , Mice , Sirtuin 1/biosynthesis
18.
PLoS Pathog ; 8(10): e1002979, 2012.
Article En | MEDLINE | ID: mdl-23133373

The dynamics of reductive genome evolution for eukaryotes living inside other eukaryotic cells are poorly understood compared to well-studied model systems involving obligate intracellular bacteria. Here we present 8.5 Mb of sequence from the genome of the microsporidian Trachipleistophora hominis, isolated from an HIV/AIDS patient, which is an outgroup to the smaller compacted-genome species that primarily inform ideas of evolutionary mode for these enormously successful obligate intracellular parasites. Our data provide detailed information on the gene content, genome architecture and intergenic regions of a larger microsporidian genome, while comparative analyses allowed us to infer genomic features and metabolism of the common ancestor of the species investigated. Gene length reduction and massive loss of metabolic capacity in the common ancestor was accompanied by the evolution of novel microsporidian-specific protein families, whose conservation among microsporidians, against a background of reductive evolution, suggests they may have important functions in their parasitic lifestyle. The ancestor had already lost many metabolic pathways but retained glycolysis and the pentose phosphate pathway to provide cytosolic ATP and reduced coenzymes, and it had a minimal mitochondrion (mitosome) making Fe-S clusters but not ATP. It possessed bacterial-like nucleotide transport proteins as a key innovation for stealing host-generated ATP, the machinery for RNAi, key elements of the early secretory pathway, canonical eukaryotic as well as microsporidian-specific regulatory elements, a diversity of repetitive and transposable elements, and relatively low average gene density. Microsporidian genome evolution thus appears to have proceeded in at least two major steps: an ancestral remodelling of the proteome upon transition to intracellular parasitism that involved reduction but also selective expansion, followed by a secondary compaction of genome architecture in some, but not all, lineages.


Energy Metabolism/genetics , Genome, Fungal , Microsporidia/genetics , Proteome/genetics , Acquired Immunodeficiency Syndrome/microbiology , Biological Evolution , Evolution, Molecular , Humans , Microsporidia/isolation & purification , Mitochondria , Phylogeny , Proteomics , RNA Interference , RNA, Small Interfering , Sequence Analysis, DNA
19.
Bioinformatics ; 28(18): i562-i568, 2012 Sep 15.
Article En | MEDLINE | ID: mdl-22962482

MOTIVATION: Annotations are a key feature of many biological databases, used to convey our knowledge of a sequence to the reader. Ideally, annotations are curated manually, however manual curation is costly, time consuming and requires expert knowledge and training. Given these issues and the exponential increase of data, many databases implement automated annotation pipelines in an attempt to avoid un-annotated entries. Both manual and automated annotations vary in quality between databases and annotators, making assessment of annotation reliability problematic for users. The community lacks a generic measure for determining annotation quality and correctness, which we look at addressing within this article. Specifically we investigate word reuse within bulk textual annotations and relate this to Zipf's Principle of Least Effort. We use the UniProt Knowledgebase (UniProtKB) as a case study to demonstrate this approach since it allows us to compare annotation change, both over time and between automated and manually curated annotations. RESULTS: By applying power-law distributions to word reuse in annotation, we show clear trends in UniProtKB over time, which are consistent with existing studies of quality on free text English. Further, we show a clear distinction between manual and automated analysis and investigate cohorts of protein records as they mature. These results suggest that this approach holds distinct promise as a mechanism for judging annotation quality. AVAILABILITY: Source code is available at the authors website: http://homepages.cs.ncl.ac.uk/m.j.bell1/annotation. CONTACT: phillip.lord@newcastle.ac.uk.


Databases, Protein , Knowledge Bases , Molecular Sequence Annotation/standards , Proteins/chemistry , Proteins/physiology
20.
Am J Hum Genet ; 91(2): 349-57, 2012 Aug 10.
Article En | MEDLINE | ID: mdl-22863195

Osteogenesis imperfecta (OI) is a clinically and genetically heterogeneous disorder associated with bone fragility and susceptibility to fractures after minimal trauma. OI type V has an autosomal-dominant pattern of inheritance and is not caused by mutations in the type I collagen genes COL1A1 and COL1A2. The most remarkable and pathognomonic feature, observed in ~65% of affected individuals, is a predisposition to develop hyperplastic callus after fractures or surgical interventions. To identify the molecular cause of OI type V, we performed whole-exome sequencing in a female with OI type V and her unaffected parents and searched for de novo mutations. We found a heterozygous de novo mutation in the 5'-untranslated region of IFITM5 (the gene encoding Interferon induced transmembrane protein 5), 14 bp upstream of the annotated translation initiation codon (c.-14C>T). Subsequently, we identified an identical heterozygous de novo mutation in a second individual with OI type V by Sanger sequencing, thereby confirming that this is the causal mutation for the phenotype. IFITM5 is a protein that is highly enriched in osteoblasts and has a putative function in bone formation and osteoblast maturation. The mutation c.-14C>T introduces an upstream start codon that is in frame with the reference open-reading frame of IFITM5 and is embedded into a stronger Kozak consensus sequence for translation initiation than the annotated start codon. In vitro, eukaryotic cells were able to recognize this start codon, and they used it instead of the reference translation initiation signal. This suggests that five amino acids (Met-Ala-Leu-Glu-Pro) are added to the N terminus and alter IFITM5 function in individuals with the mutation.


Membrane Proteins/genetics , Osteogenesis Imperfecta/genetics , 5' Untranslated Regions/genetics , Absorptiometry, Photon , Amino Acid Sequence , Base Sequence , Child , Codon, Initiator/genetics , Computational Biology , Diphosphonates/therapeutic use , Exome/genetics , Female , Humans , Infant , Molecular Sequence Data , Osteogenesis Imperfecta/diagnostic imaging , Osteogenesis Imperfecta/drug therapy , Point Mutation/genetics , Sequence Analysis, DNA
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