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Abstract As the sister group to all other animals, ctenophores (comb jellies) are important for understanding the emergence and diversification of numerous animal traits. Efforts to explore the evolutionary processes that promoted diversification within Ctenophora are hindered by undersampling genomic diversity within this clade. To address this gap, we present the sequence, assembly and initial annotation of the genome of Beroe ovata. Beroe possess unique morphology, behavior, ecology and development. Unlike their generalist carnivorous kin, beroid ctenophores feed exclusively on other ctenophores. Accordingly, our analyses revealed a loss of chitinase, an enzyme critical for the digestion of most non-ctenophore prey, but superfluous for ctenophorivores. Broadly, our genomic analysis revealed that extensive gene loss and changes in gene regulation have shaped the unique biology of B. ovata. Despite the gene losses in B. ovata, our phylogenetic analyses on photosensitive opsins and several early developmental regulatory genes show that these genes are conserved in B. ovata. This additional sampling contributes to a more complete reconstruction of the ctenophore ancestor and points to the need for extensive comparisons within this ancient and diverse clade of animals. To promote further exploration of these data, we present BovaDB (http://ryanlab.whitney.ufl.edu/bovadb/), a portal for the B. ovata genome. 

Abstract We present JWST NIRCam imaging targeting 13z ~ 3 infrared-luminous (L_IR ∼ 5 × 10¹²L_⊙) galaxies from the ALESS survey with uniquely deep, high-resolution (0 $\stackrel{\text{″}}{.}$08–0 $\stackrel{″}{.}$16) Atacama Large Millimeter/submillimeter Array 870μm imaging. The 2.0–4.4μm (observed frame) NIRCam imaging reveals the rest-frame near-infrared stellar emission in these submillimeter-selected galaxies at the same (sub)kiloparsec resolution as the 870μm dust continuum. The newly revealed stellar morphologies show striking similarities with the dust continuum morphologies at 870μm, with the centers and position angles agreeing for most sources, clearly illustrating that the spatial offsets reported previously between the 870μm and Hubble Space Telescope morphologies were due to strong differential dust obscuration. The F444W sizes are 78% ± 21% larger than those measured at 870μm, in contrast to recent results from hydrodynamical simulations that predict larger 870μm sizes. We report evidence for significant dust obscuration in F444W for the highest-redshift sources, emphasizing the importance of longer-wavelength MIRI imaging. The majority of the sources show evidence that they are undergoing mergers/interactions, including tidal tails/plumes—some of which are also detected at 870μm. We find a clear correlation between NIRCam colors and 870μm surface brightness on  ∼1 kpc scales, indicating that the galaxies are primarily red due to dust—not stellar age—and we show that the dust structure on  ∼kpc scales is broadly similar to that in nearby galaxies. Finally, we find no strong stellar bars in the rest-frame near-infrared, suggesting the extended bar-like features seen at 870μm are highly obscured and/or gas-dominated structures that are likely early precursors to significant bulge growth. 

Cnidarians are critical members of aquatic communities and have been an experimental system for a diversity of research areas ranging from development to biomechanics to global change biology. Yet, we still lack a well-resolved, taxonomically balanced cnidarian tree of life to place this research in appropriate phylogenetic context. To move towards this goal, we combined data from 26 new anthozoan transcriptomes with 86 previously published cnidarian and outgroup datasets to generate two 748-locus alignments containing 123,051 (trimmed) and 449,935 (untrimmed) amino acids. We estimated maximum likelihood phylogenies for both matrices under partitioned and unpartitioned site-homogeneous and site-heterogenous models of substitution. We used the resulting topology to constrain a phylogenetic analysis of 1,814 small subunit ribosomal (18S) gene sequences from GenBank. Our results confirm the position of Ceriantharia (tube-dwelling anemones), a historically recalcitrant group, as sister to the rest of Hexacorallia across all phylogenies regardless of data matrix or model choice. We find unanimous support for the sister relationships of Scleractinia and Corallimorpharia and of Endocnidozoa and Medusozoa. We propose the name Coralliformes for the clade uniting scleractinians and corallimorpharians and the name Operculozoa for the clade uniting endocnidozoans and medusozoans. Of the 229 genera with more than a single representative in our 18S hybrid phylogeny, 47 (21%) were identified as monophyletic, providing a starting point for a number of taxonomic revisions. Together, these data are an invaluable resource for comparative cnidarian research and provide perspective to guide future refinement of cnidarian systematics. 

The standard model for Ca 2+ oscillations in insulin-secreting pancreatic β cells centers on Ca 2+ entry through voltage-activated Ca 2+ channels. These work in combination with ATP-dependent K + channels, which are the bridge between the metabolic state of the cells and plasma membrane potential. This partnership underlies the ability of the β cells to secrete insulin appropriately on a minute-to-minute time scale to control whole body plasma glucose. Though this model, developed over more than 40 years through many cycles of experimentation and mathematical modeling, has been very successful, it has been challenged by a hypothesis that calcium-induced calcium release from the endoplasmic reticulum through ryanodine or inositol trisphosphate (IP3) receptors is instead the key driver of islet oscillations. We show here that the alternative model is in fact incompatible with a large body of established experimental data and that the new observations offered in support of it can be better explained by the standard model. 

A mixture ofN,N,N′-trisubstituted thiourea and cyclicN,N,N′,N′-tetrasubstituted selenourea precursors were used to synthesize three monolayer thick CdS_1−xSe_xnanoplatelets in a single synthetic step. 

Abstract Innexins facilitate cell–cell communication by forming gap junctions or nonjunctional hemichannels, which play important roles in metabolic, chemical, ionic, and electrical coupling. The lack of knowledge regarding the evolution and role of these channels in ctenophores (comb jellies), the likely sister group to the rest of animals, represents a substantial gap in our understanding of the evolution of intercellular communication in animals. Here, we identify and phylogenetically characterize the complete set of innexins of four ctenophores: Mnemiopsis leidyi, Hormiphora californensis, Pleurobrachia bachei, and Beroe ovata. Our phylogenetic analyses suggest that ctenophore innexins diversified independently from those of other animals and were established early in the emergence of ctenophores. We identified a four-innexin genomic cluster, which was present in the last common ancestor of these four species and has been largely maintained in these lineages. Evidence from correlated spatial and temporal gene expression of the M. leidyi innexin cluster suggests that this cluster has been maintained due to constraints related to gene regulation. We describe the basic electrophysiological properties of putative ctenophore hemichannels from muscle cells using intracellular recording techniques, showing substantial overlap with the properties of bilaterian innexin channels. Together, our results suggest that the last common ancestor of animals had gap junctional channels also capable of forming functional innexin hemichannels, and that innexin genes have independently evolved in major lineages throughout Metazoa. 

Cnidocytes (i.e., stinging cells) are an unequivocally novel cell type used by cnidarians (i.e., corals, jellyfish, and their kin) to immobilize prey. Although they are known to share a common evolutionary origin with neurons, the developmental program that promoted the emergence of cnidocyte fate is not known. Using functional genomics in the sea anemone, Nematostella vectensis , we show that cnidocytes develop by suppression of neural fate in a subset of neurons expressing RFamide. We further show that a single regulatory gene, a C 2 H 2 -type zinc finger transcription factor (ZNF845), coordinates both the gain of novel (cnidocyte-specific) traits and the inhibition of ancestral (neural) traits during cnidocyte development and that this gene arose by domain shuffling in the stem cnidarian. Thus, we report a mechanism by which a truly novel regulatory gene (ZNF845) promotes the development of a truly novel cell type (cnidocyte) through duplication of an ancestral cell lineage (neuron) and inhibition of its ancestral identity (RFamide). 

Insulin is secreted in a pulsatile pattern, with important physiological ramifications. In pancreatic β-cells, which are the cells that synthesize insulin, insulin exocytosis is elicited by pulses of elevated intracellular Ca 2+ initiated by bursts of electrical activity. In parallel with these electrical and Ca 2+ oscillations are oscillations in metabolism, and the periods of all of these oscillatory processes are similar. A key question that remains unresolved is whether the electrical oscillations are responsible for the metabolic oscillations via the effects of Ca 2+ , or whether the metabolic oscillations are responsible for the electrical oscillations due to the effects of ATP on ATP-sensitive ion channels? Mathematical modeling is a useful tool for addressing this and related questions as modeling can aid in the design of well-focused experiments that can test the predictions of particular models and subsequently be used to improve the models in an iterative fashion. In this article, we discuss a recent mathematical model, the Integrated Oscillator Model (IOM), that was the product of many years of development. We use the model to demonstrate that the relationship between calcium and metabolism in beta cells is symbiotic: in some contexts, the electrical oscillations drive the metabolic oscillations, while in other contexts it is the opposite. We provide new insights regarding these results and illustrate that what might at first appear to be contradictory data are actually compatible when viewed holistically with the IOM.