Biology subjects

Bendena, W. G.

Publications and source records attributed to Bendena, W. G..

5 recordsLinked to original sources

bioRxiv2026

Characterization of NPR-14 in the Regulation of Sleep-Like Behaviour in Caenorhabditis elegans

Sleep-like quiescence is an evolutionarily conserved state essential for physiological homeostasis; however, its dysregulation can lead to sleep disorders such as narcolepsy, which can be caused by abnormal neuropeptide signaling. In Caenorhabditis elegans, the G-protein-coupled receptor NPR-14 belongs to the orexin/allatotropin receptor family and has been proposed as a homolog of mammalian orexin receptors. Using npr-14 loss-of-function (lf) mutants, we demonstrate that NPR-14 promotes arousal and inhibits sleep-like quiescence. npr-14(lf) mutants exhibit prolonged quiescence, reduced locomotion, impaired sensory responses, and metabolic defects including elevated fat accumulation and decreased feeding and egg-laying. NPR-14 is expressed in ASH and ASI sensory neurons and in GABAergic DD, VD, and VC motor neurons, positioning it to modulate both sensory-motor integration and motor output directly. Genetic epistasis analysis revealed that NPR-14 functions upstream of EGL-4/protein kinase G (PKG): egl-4 loss-of-function suppressed the enhanced quiescence of npr-14 mutants, while egl-4 gain-of-function phenotypes were not enhanced by loss of npr-14. Caffeine treatment partially suppressed npr-14 mutant quiescence, suggesting convergence with adenosine-sensitive arousal pathways. These findings establish NPR-14 as a wake-promoting GPCR that inhibits EGL-4/PKG signalling to regulate quiescence and arousal. The NPR-14-EGL-4 axis suggests functional parallels to arousal regulation in other systems.

genetics↗

bioRxiv2025

Single-cell analyses reveal scyphozoan conserved and specific genes contribution during tissue regeneration in two jellyfish

The phylum Cnidaria is the outgroup of Bilateria and includes sea anemones, corals, hydroids, and jellyfish. Cnidarians play crucial ecological roles in marine ecosystems, including the formation of highly diverse and productive coral reefs, and acting as important predator and prey species. Cnidarians are also well known for their remarkable regeneration capacities. Here, we report single-cell RNA sequencing during bell regeneration in two species of scyphozoans or true jellyfish, Aurelia coerulea and Rhopilema esculentum. We delineated 12 cell populations in Aurelia and Rhopilema, and revealed their respective marker genes and enriched gene pathways. Conserved transcription factor Otx and Wnt/ {beta}-catenin signalling pathway genes were identified during regeneration processes. Additionally, we discovered two conserved, sequentially activated modules during regeneration, with stem cells, gastrodermal cells, neural cells, and secretory gland cells modulated in the first phase, followed by cnidocytes in the second phase. Further comparison among cnidarian genomes identified a suite of scyphozoan lineage-specific genes, a subset of which were frequently significantly expressed in cnidocytes in both jellyfish species during the first phase of regeneration. This study reveals key insights into the evolution and contribution of conserved and novel genes to the formation of lineage-specific genetic networks and biological processes.

evolutionary biology↗

bioRxiv2024

Response of protein coding genes and microRNAs to temperature changes in four insect species

Insects are the most abundant described living creatures in the world, and they play important roles in our global ecosystem. Climate change affects global biodiversity, and researchers in many fields are striving to better understand the impact of the climate crisis. One such endeavour is the study of temperature-dependent effects on insects. At present, we know little of how climate affects gene expression in insects of different sexes. Here, we took four species of fruit flies of the genus Drosophila (D. melanogaster, D. virilis, D. pseudoobscura, and D. erecta), and subjected the male and female flies of each species to three different temperatures to test their sex-specific gene expression responses. A total of 144 transcriptomic profiles of protein-coding genes and microRNAs were generated. We found that, at the same temperature, there were more male-biased than female-biased protein-coding genes and microRNAs in all four investigated drosophilid species. Interestingly, upon temperature changes, there were more differentially expressed protein-coding genes in females than in males in all four investigated species, while the microRNAs were highly species- and sex-specific. This study provides the first evidence that sex-biased protein-coding gene and microRNA expression responses to temperature change differ between insect species within the same genus, and demonstrates the complexity of sex-specific responses of insects to climate change. HighlightsO_LIAt the same temperature, protein coding gene and microRNA expression showed a greater bias towards males than towards females in all four tested insect species. C_LIO_LIIn response to increasing temperature, females of all 4 tested species exhibited more differentially expressed genes than did males, and enrichment analyses showed that they are species-specific. C_LIO_LIDifferentially expressed microRNAs did not show a conserved trend between insects upon temperature changes. C_LIO_LISex-specific gene and microRNA expression of insects in response to climate change evidently involves a complex adaptation mechanism. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/591511v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@1037b18org.highwire.dtl.DTLVardef@18683f3org.highwire.dtl.DTLVardef@40dee5org.highwire.dtl.DTLVardef@e9a108_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

bioRxiv2020

Horseshoe crab genomes reveal the evolutionary fates of genes and microRNAs after three rounds (3R) of whole genome duplication

Whole genome duplication (WGD) has occurred in relatively few sexually reproducing invertebrates. Consequently, the WGD that occurred in the common ancestor of horseshoe crabs ~135 million years ago provides a rare opportunity to decipher the evolutionary consequences of a duplicated invertebrate genome. Here, we present a high-quality genome assembly for the mangrove horseshoe crab Carcinoscorpius rotundicauda (1.7Gb, N50 = 90.2Mb, with 89.8% sequences anchored to 16 pseudomolecules, 2n = 32), and a resequenced genome of the tri-spine horseshoe crab Tachypleus tridentatus (1.7Gb, N50 = 109.7Mb). Analyses of gene families, microRNAs, and synteny show that horseshoe crabs have undergone three rounds (3R) of WGD, and that these WGD events are shared with spiders. Comparison of the genomes of C. rotundicauda and T. tridentatus populations from several geographic locations further elucidates the diverse fates of both coding and noncoding genes. Together, the present study represents a cornerstone for a better understanding of the consequences of invertebrate WGD events on evolutionary fates of genes and microRNAs at individual and population levels, and highlights the genetic diversity with practical values for breeding programs and conservation of horseshoe crabs.

evolutionary biology↗

bioRxiv2019

Varying constraints impact the miR-6/5/4/286/3/309 microRNA cluster in Drosophila leg development

A striking feature of microRNAs is that they are often clustered in the genomes of animals. The functional and evolutionary consequences of this clustering remain obscure. Here, we investigated a microRNA cluster miR-6/5/4/286/3/309 that is conserved across drosophilid lineages. Small RNA sequencing revealed expression of this microRNA cluster in Drosophila melanogaster leg discs, and conditional overexpression of the whole cluster resulted in leg appendage shortening. Transgenic overexpression lines expressing different combinations of microRNA cluster members were also constructed. Expression of individual microRNAs from the cluster resulted in a normal wild-type phenotype, but either the expression of several ancient microRNAs together (miR-5/4/286/3/309) or more recently evolved clustered microRNAs (miR-6-1/2/3) can recapitulate the phenotypes generated by the whole-cluster overexpression. Screening of transgenic fly lines revealed down-regulation of leg patterning gene cassettes in generation of the leg-shortening phenotype. Furthermore, cell transfection with different combinations of microRNA cluster members revealed a suite of downstream genes targeted by all cluster members, as well as complements of targets that are unique for distinct microRNAs. Considering together the microRNA targets and the evolutionary ages of each microRNA in the cluster demonstrates the importance of microRNA clustering, where new members can reinforce and modify the selection forces on both the cluster regulation and the gene regulatory network of existing microRNAs.

evolutionary biology↗