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Moody, E. R. R.

Publications and source records attributed to Moody, E. R. R..

10 recordsLinked to original sources

Evaluating 18S Phylogenetic Placement Accuracy to Uncover Hidden Diversity in Early Branching Animals

Small subunit ribosomal RNA (SSU rRNA) - 18S in eukaryotes - is a gene universally present across the Tree of Life and it was central in resolving ancient relationships in early molecular phylogenies. Nowadays, despite multi-locus phylogenomic approaches dominate, SSU rRNA sequences still serv as a molecular identifier of biodiversity. Phylogenetic placement uses a reference phylogeny and a given evolutionary model to annotate taxonomically environmental DNA. As such, it enables more accurate identification of divergent sequences that may belong to unknown lineages across the Tree of Life. Here we first created the largest dataset of 18S sequences belonging to non-Bilateria metazoans, by curating the sequences found in PR2 database. We then used it as a case study to test the performance of different 18S-based barcodes (V4, V9, and full-length 18S) within a phylogenetic placement framework. Employing a series of sensitivity analyses, we found that the V9 region generally lacks sufficient phylogenetic signal for reliable placements in most of the cases. The V4 region is accurate when the environmental diversity is well represented in the reference tree but struggles with divergent lineages. Full-length 18S overcome short-read limitations and emerges as the most robust option to uncover unknown major clades. Finally, we apply phylogenetic placement to empirical environmental 18S data. We observe geographical variation in non-bilaterians communities and recover a putative clade of early-branching Ctenophora based on long-sequence barcodes.

evolutionary biology↗

The prokaryotic origins of the COMMD protein family involved in eukaryotic membrane trafficking

The ten eukaryotic COMMD proteins are core components of the Commander complex, with central roles in endosomal membrane trafficking and signalling. Each protein has an -helical N-terminal (HN) domain with a C-terminal copper metabolism gene MURR1 (COMM) domain. These ten family members assemble into a heterodecameric ring composed of five specific heterodimers. In this work we have combined structural homology searches with genome-wide predicted structures to identify ancestral COMMD-like proteins that exist as single genes in Bacteria and Archaea. Although there is limited sequence similarity to the eukaryotic proteins the bacterial and archaeal COMMD-like proteins are predicted to form homomeric ring-shaped assemblies like their eukaryotic counterparts. Our biophysical studies, crystal and cryo-EM structures confirm COMMD-like proteins readily form homooligomeric rings composed of eight or ten subunits assembled from core dimeric building blocks and inter-dimer interactions that are analogous to the heterodecameric core structure of the eukaryotic Commander complex. Phylogenetic analyses using amino acid sequences and FoldSeek structural alphabet (3Di) infer that the closest identified relatives to the eukaryotic COMMD proteins are found in Myxococcota bacteria. These findings indicate that COMMD genes emerged early in eukaryotic evolution through multiple rounds of duplication from a single ancestral gene likely acquired from bacteria.

biochemistry↗

Identification of a VPS29 isoform with restricted association to Retriever and Retromer accessory proteins through auto-inhibition.

The endosomal-lysosomal network is a hub of organelles that orchestrate the dynamic sorting of hundreds of integral membrane proteins to maintain cellular homeostasis. VPS29 is a central conductor of this network through its assembly into Retromer, Retriever and Commander endosomal sorting complexes, and its role in regulating RAB GTPase activity. Two VPS29 isoforms have been described, VPS29A and VPS29B, that differ solely in their amino-terminal sequences. Here we identify a third VPS29 isoform, which we term VPS29C, that harbours an extended amino-terminal sequence compared to VPS29A and VPS29B. Through a combination of AlphaFold predictive modelling, in vitro complex reconstitution, mass spectrometry and molecular cell biology, we find that the amino-terminal VPS29C extension constitutes an autoinhibitory sequence that limits access to a hydrophobic groove necessary for effector protein recruitment to Retromer, and association with Retriever and Commander. VPS29C is therefore unique in its ability to uncouple Retromer-dependent cargo sorting from the broader roles of VPS29A and VPS29B in regulating the endosomal-lysosomal network through accessory protein recruitment. Our identification and characterisation of VPS29C points to additional complexity in the differential subunit assembly of Retromer, an important consideration given the increasing interest in Retromer as a potential therapeutic target in neurodegenerative diseases. SIGNIFICANCE STATEMENTThe endosomal-lysosomal network is essential for normal cellular function with network defects being associated with numerous neurodegenerative diseases. Two heterotrimeric complexes, Retromer and Retriever, control transmembrane protein recycling through the network. Of these, reduced Retromer expression is observed in Alzheimers disease and Retromer mutations lead to familial Parkinsons disease. Here, we identify and characterise a new isoform of VPS29, a subunit shared between Retromer and Retriever. We reveal how this isoform, VPS29C, adopts an auto-inhibitory conformation to limit its association into Retriever and restrict the binding of VPS29C-containing Retromer to accessory proteins vital for regulating network function. By revealing added complexity in Retromer assembly and function, we provide new insight into Retromers potential as a therapeutic target in neurodegenerative diseases.

cell biology↗

Evolutionarily conserved principles of ESCRT-III-mediated membrane remodelling revealed by a two-subunit Asgard archaeal system

ESCRT-III proteins assemble into composite polymers that undergo stepwise changes in composition and structure to deform membranes across the tree of life. Here, using a phylogenetic analysis we demonstrate that the two ESCRT-III proteins present in our closest archaeal relatives are evolutionarily related to B-type and A-type eukaryotic paralogues, which initiate and execute membrane remodelling, respectively. This deep homology is reflected in ESCRT-III structure and function as demonstrated by the fact that ESCRT-IIIB assembles into parallel arrays on planar membranes to initiate membrane deformation, and is required to recruit ESCRT-IIIA to generate composite polymers. ESCRT-IIIA homopolymers can then remodel membranes into tubes, as a likely prelude to scission. Taken together, this analysis reveals a set of conserved principles governing ESCRT-III-dependent membrane remodelling that first emerged with the evolution of a two-component ESCRT-III system in the Asgard archaea, and which continue to underlie complex multi-component, ESCRT-III-dependent membrane remodelling in eukaryotes.

evolutionary biology↗

An evolutionary timescale for Bacteria calibrated using the Great Oxidation Event

Most of lifes diversity and history is microbial but it has left a meagre fossil record, greatly hindering understanding of evolution in deep time. However, the co-evolution of life and the Earth system has left signatures of bacterial metabolism in the geochemical record, most conspicuously the Great Oxidation Event (GOE) [~]2.33 billion years ago (Ga, (Poulton et al. 2021)), in which oxygenic photosynthesis and tectonism (Eguchi, Seales, and Dasgupta 2019) transformed Earths biosphere from dominantly anaerobic to aerobic. Here, we combine machine learning and phylogenetic reconciliation to infer ancestral transitions to aerobic lifestyles during bacterial evolution. Linking these transitions to the GOE provides new constraints to infer the timetree of Bacteria. We find that extant bacterial phyla are truly ancient, having radiated in the Archaean and the Proterozoic: the oldest include Bacillota (Firmicutes), which radiated 3.1-3.7 Ga, Cyanobacteria (3.3-3.5 Ga) and Patescibacteria (3-3.5 Ga). We show that most bacterial phyla were ancestrally anaerobic and that most transitions to an aerobic lifestyle post-dated the GOE. Our analyses trace oxygen production and consumption back to Cyanobacteria. From that starting point, horizontal transfer seeded aerobic lifestyles across bacterial diversity over hundreds of millions of years. Our analyses demonstrate that the diversification of aerobes proceeded in two waves corresponding to the GOE and to a second sustained rise in atmospheric O2 at the dawn of the Palezoic (Krause et al. 2022).

evolutionary biology↗

ATP synthase evolution on a cross-braced dated tree of life

The timing of early cellular evolution from the divergence of Archaea and Bacteria to the origin of eukaryotes remains poorly constrained. The ATP synthase complex is thought to have originated prior to the Last Universal Common Ancestor (LUCA) and analyses of ATP synthase genes, together with ribosomes, have played a key role in inferring and rooting the tree of life. Here we reconstruct the evolutionary history of ATP synthases using an expanded sampling of Archaea, Bacteria, and eukaryotes. We developed a phylogenetic cross-bracing approach making use of endosymbioses and ancient gene duplications of the major ATP synthase subunits to infer a highly resolved, dated species tree and establish an absolute timeline for ATP synthase evolution. Our analyses show that the divergence of the ATP synthase into F- and A/V-type lineages, was a very early event in cellular evolution dating back to more than 4Ga potentially predating the diversification of Archaea and Bacteria. Our cross-braced, dated tree of life also provides insight into more recent evolutionary transitions including eukaryogenesis, showing that the eukaryotic nuclear and mitochondrial lineages diverged from their closest archaeal (2.67-2.19Ga) and bacterial (2.58-2.12Ga) relatives at roughly the same time, with the nuclear stem being moderately longer.

evolutionary biology↗

Ancient origin and evolution of microbial mercury methylation

The origin of microbial mercury methylation has long been a mystery. Here we employed genome-resolved phylogenetic analyses to decipher the evolution of the mercury methylating gene, hgcAB, constrain the ancestral origin of the hgc operon, and explain the distribution of hgc in Bacteria and Archaea. We infer the extent to which vertical inheritance and horizontal gene transfer have influenced the evolution of mercury methylators and hypothesize that evolution of this trait bestowed the ability to produce an antimicrobial compound (MeHg+) on a potentially resource-limited early Earth. We speculate that, in response, the evolution of MeHg+-detoxifying alkylmercury lyase (encoded by merB) reduced a selective advantage for mercury methylators and resulted in widespread loss of hgc in Bacteria and Archaea. SignificanceNeurotoxic methylmercury (MeHg+(aq)) is synthesized from HgII(aq) in the environment by microorganisms possessing the gene pair hgcAB. Our phylogenetic analyses elucidate the origin and evolution of the hgc operon, and support a hypothesis that mercury methylation evolved as an antimicrobial production mechanism, possibly from competition for limited resources on the early Earth. We infer from our analyses that hgc has been primarily vertically inherited in Bacteria and Archaea, with extensive parallel loss, and note that few taxa possessing hgc also possess the gene encoding for MeHg+ demethylation, merB. Our findings support the interpretation that merB evolved as a defense mechanism against the evolution of microbial HgII(aq) methylation.

evolutionary biology↗

Mechanistic basis for SNX27-Retromer coupling to ESCPE-1 in promoting endosomal cargo recycling.

Sorting nexin-27 (SNX27)-Retromer is an endosomal sorting complex that orchestrates endosome-to-plasma membrane recycling of hundreds of internalized receptors, channels and transporters, enzymes and adhesion molecules. While SNX27-Retromer is essential for development, subtle functional defects are observed in human disease, most notably neurodegenerative and neurological disorders. Achieving a thorough mechanistic dissection of SNX27-Retromer is central to understanding endosomal sorting in health and disease. Here we combine biochemical, structural and cellular analyses to establish the mechanistic basis through which SNX27-Retromer couples to the membrane tubulating ESCPE-1 complex (Endosomal SNX-BAR sorting complex for promoting exit 1). We show that a conserved surface in the FERM (4.1/ezrin/radixin/moesin) domain of SNX27 directly binds acidic-Asp-Leu-Phe (aDLF) motifs in the disordered amino-termini of the SNX1 and SNX2 subunits of ESCPE-1. This interaction hands-over SNX27-Retromer captured integral membrane proteins into ESCPE-1 tubular profiles to promote their cell surface recycling. Through phylogenetic analysis, we reveal that SNX27:Retromer:ESCPE-1 assembly evolved in a stepwise manner during the early evolution of metazoans, which reflects the increasing complexity of endosomal sorting from the ancestral opisthokont to modern animals.

cell biology↗

Molecular mechanism for kinesin-1 direct membrane recognition

The cargo-binding capabilities of cytoskeletal motor proteins have expanded during evolution through both gene duplication and alternative splicing. For the light chains of the kinesin-1 family of microtubule motors, this has resulted in an array of carboxy-terminal domain sequences of unknown molecular function. Here, combining phylogenetic analyses with biophysical, biochemical and cell biology approaches we identify a highly conserved membrane-induced curvature-sensitive amphipathic helix within this region of a newly defined subset of long kinesin light chain paralogues and splice isoforms. This helix mediates the direct binding of kinesin-1 to lipid membranes. Membrane binding requires specific anionic phospholipids and is important for kinesin-1 dependent lysosome positioning, a canonical activity that until now has been attributed exclusively the recognition of organelle-associated cargo adaptor proteins. This leads us to propose a new protein-lipid coincidence detection framework for kinesin-1 mediated organelle transport.

cell biology↗

Universal markers support a long inter-domain branch between Archaea and Bacteria

Core gene phylogenies provide a window into early evolution, but different gene sets and analytical methods have yielded substantially different views of the tree of life. Trees inferred from a small set of universal core genes have typically supported a long branch separating the archaeal and bacterial domains. By contrast, recent analyses of a broader set of non-ribosomal genes have suggested that Archaea may be less divergent from Bacteria, and that estimates of inter-domain distance are inflated due to accelerated evolution of ribosomal proteins along the inter-domain branch. Resolving this debate is key to determining the diversity of the archaeal and bacterial domains, the shape of the tree of life, and our understanding of the early course of cellular evolution. Here, we investigate the evolutionary history of the marker genes key to the debate. We show that estimates of a reduced Archaea-Bacteria (AB) branch length result from inter-domain gene transfers and hidden paralogy in the expanded marker gene set. By contrast, analysis of a broad range of manually curated marker gene datasets from an evenly sampled set of 700 Archaea and Bacteria reveal that current methods likely underestimate the AB branch length due to substitutional saturation and poor model fit; that the best-performing phylogenetic markers tend to support longer inter-domain branch lengths; and that the AB branch lengths of ribosomal and non-ribosomal marker genes are statistically indistinguishable. Furthermore, our phylogeny inferred from the 27 highest-ranked marker genes recovers a clade of DPANN at the base of the Archaea, and places CPR within Bacteria as the sister group to the Chloroflexota.

evolutionary biology↗