Publications by authors named "Telford M"
Article Synopsis
- The evolutionary origin of Bilateria is unclear, but similarities between cnidarian-like larvae and simple flatworms suggest a connection, linking Xenacoelomorpha as a potential early branch of Bilateria.
- This study focuses on assembling and analyzing the genome of a marine xenacoelomorph, discovering it has a genome size of ~111 Mbp with characteristics similar to other bilaterians.
- The findings indicate that despite its simple body plan, the xenacoelomorph has a complex genome and retains many features typical of bilaterians, challenging previous assumptions about its evolutionary simplicity.
Article Synopsis
- Ancestral reconstruction is a method used to study the evolutionary history of gene families, often utilizing Dollo parsimony, which assumes complex traits cannot be regained after they are lost.
- The study hypothesizes that Dollo parsimony is unsuitable for this task because it may not accurately reflect the complexities of molecular evolution, such as false orthology due to sequence convergence or lateral gene transfer.
- The research compares Dollo parsimony with a maximum likelihood approach, revealing that Dollo parsimony often overestimates ancestral gene content, especially in deeper evolutionary branches, thus supporting the hypothesis that it is not an appropriate method for reconstruction based on sequence homology.
Article Synopsis
- Phylogenetic research has grouped previously isolated groups like nematodermatids, acoels, and xenoturbelids into a new phylum called Xenacoelomorpha.
- Some studies suggest that Xenacoelomorpha may be closely related to Ambulacraria, while others indicate it could be a sibling group to all Bilateria.
- Research using single-cell RNA sequencing in the marine worm Xenoturbella bocki reveals similarities in nerve nets, muscles, and glands that support the idea of shared evolutionary traits among various animal groups, reinforcing the monophyly of Xenacoelomorpha.
Pelagic larval stages are widespread across animals, yet it is unclear whether larvae were present in the last common ancestor of animals or whether they evolved multiple times due to common selective pressures. Many marine larvae are at least superficially similar; they are small, swim through the beating of bands of cilia, and sense the environment with an apical organ. To understand these similarities, we have generated single-cell atlases for marine larvae from two animal phyla and have compared their cell types.
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- Traditional methods of inferring deep phylogenies have favored protein sequences over DNA, believing proteins are more reliable due to lower rates of homoplasy and saturation.
- This study challenges that view, showing through simulations that DNA sequences can be just as effective, if not more so, for reconstructing accurate phylogenetic trees.
- Additionally, DNA analysis offers a significant computational advantage, enabling the use of more advanced models that account for variations in substitution processes, making it a promising method for phylogenetic inference.
Small proteins perform a diverse array of functions, from microbial competition, to endocrine signaling, to building biomaterials. Microbial systems that can produce recombinant small proteins enable discovery of new effectors, exploration of sequence activity relationships, and have the potential for delivery. However, we lack simple systems for controlling small-protein secretion from Gram-negative bacteria.
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- The tiger flatworm, Prostheceraeus crozieri, has a unique planktonic larval stage known as Müller's larva, featuring eight lobes and three eyes, with limited prior research on its apical organ structure.
- This study presents detailed ultrastructural data and 3D reconstructions of the apical organ, which consists of two main components: the apical tuft complex with long cilia and anchor cells, and the dorso-apical tuft complex with sensory neurons.
- The research suggests a potential homology between the apical organ's components in P. crozieri and similar structures in other spiralian larvae, hinting at evolutionary connections among these species.
Unlabelled: Microcins are peptide antibiotics secreted by Gram-negative bacteria that inhibit the growth of neighboring microbes. They are exported from the cytosol to the environment in a one-step process through a specific type I secretion system (T1SS). While the rules governing export of natural or non-native substrates have been resolved for T1SSs that secrete large proteins, relatively little is known about substrate requirements for peptides exported through T1SSs that secrete microcins.
View Article and Find Full Text PDFThe Y chromosome can yield a unique perspective into the study of human demographic history. However, due to the repetitive nature of part of its sequence, only a small set of regions are suitable for variant calling and discovery from short-read sequencing data. These regions combined represent 8.
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- - Polyclad flatworms, like Prostheceraeus crozieri, are important for studying evolutionary traits due to their relative primitiveness compared to other flatworms.
- - Researchers extracted high molecular weight DNA and sequenced the genome of P. crozieri, which is large (2.07 Gb) and highly repetitive (67.9%).
- - The assembly includes 43,325 annotated genes and shows significant intron sizes and transposable elements, providing a valuable resource for future biological studies.
Human herpesvirus diversity is altered in HLA class I binding peptides.
Proc Natl Acad Sci U S A
May 2022
Herpesviruses are ubiquitous, genetically diverse DNA viruses, with long-term presence in humans associated with infrequent but significant pathology. Human leukocyte antigen (HLA) class I presents intracellularly derived peptide fragments from infected tissue cells to CD8+ T and natural killer cells, thereby directing antiviral immunity. Allotypes of highly polymorphic HLA class I are distinguished by their peptide binding repertoires.
View Article and Find Full Text PDFObjective: There is public concern regarding rural workforce shortages and closure of smaller obstetric centres.
Aim: To identify whether safety is a concern for Murrumbidgee hospitals that fit primary medical care models and ascertain general practitioner (GP) obstetricians' perspectives regarding the benefits and challenges to practising in the region.
Design: Mixed-method retrospective analysis of selected outcomes in the NSW Mothers and Babies Reports 2012-2015 and semi-structured interviews with GP obstetricians.
The authors wish to make the following correction to this paper [...
View Article and Find Full Text PDFBackground: The Northern Sydney Local Health District was one of the first health regions to be affected by COVID-19 in Australia.
Aims: To describe the clinical characteristics, risk factors and outcomes in our low-prevalence Australian population.
Methods: This is a retrospective analysis of 517 laboratory-confirmed COVID-19 cases between January and June 2020.
Article Synopsis
- The emergence of CRISPR and molecular tools allows for the mapping of cell lineages via induced DNA mutations, with the potential to apply this method to more complex organisms in the future.
- A DREAM challenge was organized to test the performance of lineage reconstruction algorithms using both real data from C. elegans and simulated data from Mus musculus, comparing 22 different approaches.
- Some methods showed strong performance, but structural challenges in the lineage trees affected results; using smaller sub-trees to train algorithms was beneficial for improving the accuracy of larger tree reconstructions.
Article Synopsis
- Recent advancements in genetics and imaging technology are enabling researchers to reconstruct cell lineages, which track the history of cell divisions using live microscopy and molecular recorders.
- A key research goal is to combine this lineage information with spatial data and cellular identities to create a more comprehensive understanding of cell relationships.
- The web-based tool CeLaVi facilitates this integration by allowing users to interact with cell lineage data, visualize spatial distributions and cell characteristics in 3D, and annotate cells, enhancing the exploration of complex biological information.
Article Synopsis
- Bilateria are split into two main groups: Protostomia (which includes Ecdysozoa and Lophotrochozoa) and Deuterostomia (which includes Chordata and Xenambulacraria), with Protostomia consistently showing strong phylogenetic support.
- Recent studies suggest that Deuterostomia's classification is questionable, as its support is weak and often comparable to paraphyletic groups.
- Errors in tree reconstruction and the nature of genetic data may lead to misleading conclusions about Deuterostome monophyly and indicate that the ancestor of bilaterians might have had traits similar to deuterostomes, impacting our understanding of early animal evolution.
Article Synopsis
- The study explores how having complete gene sets from various organisms enables researchers to find unique or lost genes in different clades, which is essential for building phylogenetic trees and understanding evolutionary changes.
- The authors use simulations to create ortholog sets that have no gains or losses and find that errors in identifying these orthologs increase as evolutionary rates rise.
- Their findings indicate that inaccuracies in orthology prediction can significantly impact downstream analyses, suggesting that future studies should consider these errors when interpreting gene evolution patterns.
Article Synopsis
- The use of protein and nucleic acid sequences has dramatically improved our ability to reconstruct the tree of life, allowing scientists to analyze vast amounts of data.
- Despite these advancements, the phylogenetic results are still often controversial due to conflicting findings from large studies, indicating that errors still persist.
- These errors mainly stem from systematic biases in sequence evolution, which are recognized but require careful measures to minimize their impact on research outcomes.
The evolutionary relationships of two animal phyla, Ctenophora and Xenacoelomorpha, have proved highly contentious. Ctenophora have been proposed as the most distant relatives of all other animals (Ctenophora-first rather than the traditional Porifera-first). Xenacoelomorpha may be primitively simple relatives of all other bilaterally symmetrical animals (Nephrozoa) or simplified relatives of echinoderms and hemichordates (Xenambulacraria).
View Article and Find Full Text PDFThe human herpesvirus 6 (HHV-6) -A and -B are two dsDNA beta-herpesviruses infectingalmost the entire worldwide population. These viruses have been implicated in multipleneurological conditions in individuals of various ages and immunological status, includingencephalitis, epilepsy, and febrile seizures. HHV-6s have also been suggested as playing a role inthe etiology of neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease.
View Article and Find Full Text PDFThe Epstein-Barr Virus (EBV) infects the vast majority of human individuals worldwide (~90%) and is associated with several diseases, including different types of cancer and multiple sclerosis, which show wide variation in incidence among global geographical regions. Genetic variants in EBV genomic sequences have been used to determine the geographical structure of EBV isolates, but our understanding of EBV diversity remains highly incomplete. We generated sequences for 13 pivotal EBV genes derived from 103 healthy individuals, expanding current EBV diversity datasets with respect to both geographic coverage and number of isolates per region.
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- * Building a reliable phylogenetic tree involves key steps like identifying orthologous genes, aligning sequences, and choosing appropriate models for analysis.
- * Despite advancements in data and analysis techniques, challenges remain in creating accurate phylogenetic trees, necessitating awareness of potential errors and strategies to reduce them.
Article Synopsis
- Eukaryotic organisms can have a 'hidden break' in their 28S ribosomal RNA that splits it into two parts, mostly seen in protostome animals like arthropods and molluscs.
- A new computational method using RNA-Seq data effectively identifies this hidden break across various species, revealing that while it’s common in protostomes, it’s absent in some other taxa.
- Interestingly, only a few non-animal eukaryotes show this break, where its location implies possible convergent evolution, indicating that RNA integrity metrics may be misleading in species with this break due to underestimation in RNA quality assessments.
A growing body of literature links claimant interactions with the UK social security system and negative psychological consequences. Psychologists for social change developed a framework to outline proposed mechanisms of psychological impact from austerity. This codesigned study aimed to make an informed comment on areas of dis(agreement) between the Austerity Ailments framework and how people claiming for mental health problems describe their own experiences.
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