Medicine and Health Sciences Commons^™

Impairment Of The Glial Phagolysosomal System Drives Prion-Like Propagation Of Huntington’S Disease, Graham Davis

Theses and Dissertations

The ability of glia to tightly regulate neuronal health and homeostasis in the CNS is conserved across species. Yet, despite the ability to degrade protein aggregates, glia are vulnerable to the accumulation of neurotoxic amyloid aggregates during neurodegenerative disease progress, and even exacerbate their spread. A developing narrative highlights glia as a double-edged sword in neurodegenerative diseases: initially capable of dynamically responding to amyloid aggregate-ladened dying neurons but also capable of inducing chronic inflammation and creating seeding-competent amyloid oligomers. Thus, uncovering the mechanisms that allow glia to control aggregate deposition while preventing the neurotoxic effects and seed generation is vital …

A Drosophila Heart Optical Coherence Microscopy Dataset For Automatic Video Segmentation, Matthew Fishman, Abigail Matt, Fei Wang, Elena Gracheva, Jiantao Zhu, Xiangping Ouyang, Andrey Komarov, Yuxuan Wang, Hongwu Liang, Chao Zhou

2020-Current year OA Pubs

The heart of the fruit fly, Drosophila melanogaster, is a particularly suitable model for cardiac studies. Optical coherence microscopy (OCM) captures in vivo cross-sectional videos of the beating Drosophila heart for cardiac function quantification. To analyze those large-size multi-frame OCM recordings, human labelling has been employed, leading to low efficiency and poor reproducibility. Here, we introduce a robust and accurate automated Drosophila heart segmentation algorithm, called FlyNet 2.0+, which utilizes a long short-term memory (LSTM) convolutional neural network to leverage time series information in the videos, ensuring consistent, high-quality segmentation. We present a dataset of 213 Drosophila heart videos, equivalent …

Experimentally Induced Active And Quiet Sleep Engage Non-Overlapping Transcriptional Programs In Drosophila, Niki Anthoney, Lucy Tainton-Heap, Hang Luong, Eleni Notaras, Amber B Kewin, Qiongyi Zhao, Trent Perry, Philip Batterham, Paul J Shaw, Bruno Van Swinderen

2020-Current year OA Pubs

Sleep in mammals can be broadly classified into two different physiological categories: rapid eye movement (REM) sleep and slow-wave sleep (SWS), and accordingly REM and SWS are thought to achieve a different set of functions. The fruit fly

A Drosophila Glial Cell Atlas Reveals A Mismatch Between Transcriptional And Morphological Diversity, Inês Lago-Baldaia, Maia Cooper, Austin Seroka, Chintan Trivedi, Gareth T. Powell, Stephen W. Wilson, Sarah D. Ackerman, Vilaiwan M. Fernandes

2020-Current year OA Pubs

Morphology is a defining feature of neuronal identity. Like neurons, glia display diverse morphologies, both across and within glial classes, but are also known to be morphologically plastic. Here, we explored the relationship between glial morphology and transcriptional signature using the Drosophila central nervous system (CNS), where glia are categorised into 5 main classes (outer and inner surface glia, cortex glia, ensheathing glia, and astrocytes), which show within-class morphological diversity. We analysed and validated single-cell RNA sequencing data of Drosophila glia in 2 well-characterised tissues from distinct developmental stages, containing distinct circuit types: the embryonic ventral nerve cord (VNC) (motor) …

Synlight: A Bicistronic Strategy For Simultaneous Active Zone And Cell Labeling In The Drosophila Nervous System, Michael A. Aimino, Jesse Humenik, Michael J. Parisi, Juan Carlos Duhart, Timothy J. Mosca

Farber Institute for Neuroscience Faculty Papers

At synapses, chemical neurotransmission mediates the exchange of information between neurons, leading to complex movement, behaviors, and stimulus processing. The immense number and variety of neurons within the nervous system make discerning individual neuron populations difficult, necessitating the development of advanced neuronal labeling techniques. In Drosophila, Bruchpilot-Short and mCD8-GFP, which label presynaptic active zones and neuronal membranes, respectively, have been widely used to study synapse development and organization. This labeling is often achieved via the expression of 2 independent constructs by a single binary expression system, but expression can weaken when multiple transgenes are expressed by a single driver. Recent …

A Conditional Strategy For Cell-Type-Specific Labeling Of Endogenous Excitatory Synapses In Drosophila, Michael J. Parisi, Michael A. Aimino, Timothy J. Mosca

Farber Institute for Neuroscience Faculty Papers

Chemical neurotransmission occurs at specialized contacts where neurotransmitter release machinery apposes neurotransmitter receptors to underlie circuit function. A series of complex events underlies preand postsynaptic protein recruitment to neuronal connections. To better study synaptic development in individual neurons, we need cell-type-specific strategies to visualize endogenous synaptic proteins. Although presynaptic strategies exist, postsynaptic proteins remain less studied because of a paucity of cell-type-specific reagents. To study excitatory postsynapses with cell-type specificity, we engineered dlg1[4K], a conditionally labeled marker of Drosophila excitatory postsynaptic densities. With binary expression systems, dlg1[4K] labels central and peripheral postsynapses in larvae and adults. Using dlg1[4K], we find …

Validating A New In Vivo Model To Study Als, Izabela J. Cimachowska

Student Theses and Dissertations

Buildup of oxidative stress and mitochondrial dysfunction are well known characteristics of both sporadic and hereditary amyotrophic lateral sclerosis (ALS). While both forms of the disease seem to arise from common cellular dysfunction, the genetic disease is studied to a much greater extent. Engineering novel animal models of the sporadic form of the disease is crucial for development of druggable targets to treat ALS and understand the underlying mechanisms. Interestingly, accumulation of oxidative stress by exacerbated emission of reactive oxygen species (ROS) from presynaptic mitochondria is a hallmark of both hereditary and sporadic ALS. Previous work by our laboratory showed …

Functional Screening Of Lysosomal Storage Disorder Genes Identifies Modifiers Of Alpha-Synuclein Neurotoxicity, Meigen Yu, Hui Ye, Ruth B. De-Paula, Carl Grant Mangleburg, Timothy Wu, Tom V. Lee, Yarong Li, Duc Duong, Bridget Phillips, Carlos Cruchaga, Genevera I. Allen, Nicholas T. Seyfried, Ismael Al-Ramahi, Juan Botas, Joshua M. Shulman

2020-Current year OA Pubs

Heterozygous variants in the glucocerebrosidase (GBA) gene are common and potent risk factors for Parkinson's disease (PD). GBA also causes the autosomal recessive lysosomal storage disorder (LSD), Gaucher disease, and emerging evidence from human genetics implicates many other LSD genes in PD susceptibility. We have systemically tested 86 conserved fly homologs of 37 human LSD genes for requirements in the aging adult Drosophila brain and for potential genetic interactions with neurodegeneration caused by α-synuclein (αSyn), which forms Lewy body pathology in PD. Our screen identifies 15 genetic enhancers of αSyn-induced progressive locomotor dysfunction, including knockdown of fly homologs of GBA …

Sik3 And Wnk Converge On Fray To Regulate Glial K+ Buffering And Seizure Susceptibility, Lorenzo Lones, Aaron Diantonio

2020-Current year OA Pubs

Glial cells play a critical role in maintaining homeostatic ion concentration gradients. Salt-inducible kinase 3 (SIK3) regulates a gene expression program that controls K+ buffering in glia, and upregulation of this pathway suppresses seizure behavior in the eag, Shaker hyperexcitability mutant. Here we show that boosting the glial SIK3 K+ buffering pathway suppresses seizures in three additional molecularly diverse hyperexcitable mutants, highlighting the therapeutic potential of upregulating glial K+ buffering. We then explore additional mechanisms regulating glial K+ buffering. Fray, a transcriptional target of the SIK3 K+ buffering program, is a kinase that promotes K+ uptake by activating the Na+/K+/Cl- …

Acetyl-Coa-Mediated Autoacetylation Of Fatty Acid Synthase As A Metabolic Switch Of De Novo Lipogenesis In Drosophila, Ting Miao, Jinoh Kim, Ping Kang, Hideji Fujiwara, Fong-Fu Hsu, Hua Bai

2020-Current year OA Pubs

De novo lipogenesis is a highly regulated metabolic process, which is known to be activated through transcriptional regulation of lipogenic genes, including fatty acid synthase (FASN). Unexpectedly, we find that the expression of FASN protein remains unchanged during

Synaptic Development In Diverse Olfactory Neuron Classes Uses Distinct Temporal And Activity-Related Programs, Michael A. Aimino, Alison T. Depew, Lucas Restrepo, Timothy J. Mosca

Farber Institute for Neuroscience Faculty Papers

Developing neurons must meet core molecular, cellular, and temporal requirements to ensure the correct formation of synapses, resulting in functional circuits. However, because of the vast diversity in neuronal class and function, it is unclear whether or not all neurons use the same organizational mechanisms to form synaptic connections and achieve functional and morphologic maturation. Moreover, it remains unknown whether neurons united in a common goal and comprising the same sensory circuit develop on similar timescales and use identical molecular approaches to ensure the formation of the correct number of synapses. To begin to answer these questions, we took advantage …

Sleep-Promoting Neurons Remodel Their Response Properties To Calibrate Sleep Drive With Environmental Demands, Stephane Dissel, Markus K. Klose, Bruno Van Swinderen, Lijuan Cao, Melanie Ford, Erica M. Periandri, Joseph D. Jones, Zhaoyi Li, Paul J. Shaw

2020-Current year OA Pubs

Falling asleep at the wrong time can place an individual at risk of immediate physical harm. However, not sleeping degrades cognition and adaptive behavior. To understand how animals match sleep need with environmental demands, we used live-brain imaging to examine the physiological response properties of the dorsal fan-shaped body (dFB) following interventions that modify sleep (sleep deprivation, starvation, time-restricted feeding, memory consolidation) in Drosophila. We report that dFB neurons change their physiological response-properties to dopamine (DA) and allatostatin-A (AstA) in response to different types of waking. That is, dFB neurons are not simply passive components of a hard-wired circuit. Rather, …

Γ-Secretase Promotes Drosophila Postsynaptic Development Through The Cleavage Of A Wnt Receptor, Lucas J Restrepo, Alison T Depew, Elizabeth R Moese, Stephen R Tymanskyj, Michael J Parisi, Michael A Aimino, Juan Carlos Duhart, Hong Fei, Timothy J Mosca

Farber Institute for Neuroscience Faculty Papers

Developing synapses mature through the recruitment of specific proteins that stabilize presynaptic and postsynaptic structure and function. Wnt ligands signaling via Frizzled (Fz) receptors play many crucial roles in neuronal and synaptic development, but whether and how Wnt and Fz influence synaptic maturation is incompletely understood. Here, we show that Fz2 receptor cleavage via the γ-secretase complex is required for postsynaptic development and maturation. In the absence of γ-secretase, Drosophila neuromuscular synapses fail to recruit postsynaptic scaffolding and cytoskeletal proteins, leading to behavioral deficits. Introducing presenilin mutations linked to familial early-onset Alzheimer's disease into flies leads to synaptic maturation phenotypes …

Interchromosomal Interaction Of Homologous Stat92e Alleles Regulates Transcriptional Switch During Stem-Cell Differentiation., Matthew Antel, Romir Raj, Madona Y G Masoud, Ziwei Pan, Sheng Li, Barbara G Mellone, Mayu Inaba

Faculty Research 2022

Pairing of homologous chromosomes in somatic cells provides the opportunity of interchromosomal interaction between homologous gene regions. In the Drosophila male germline, the Stat92E gene is highly expressed in a germline stem cell (GSC) and gradually downregulated during the differentiation. Here we show that the pairing of Stat92E is always tight in GSCs and immediately loosened in differentiating daughter cells, gonialblasts (GBs). Disturbance of Stat92E pairing by relocation of one locus to another chromosome or by knockdown of global pairing/anti-pairing factors both result in a failure of Stat92E downregulation, suggesting that the pairing is required for the decline in transcription. …

Distinct Developmental And Degenerative Functions Of Sarm1 Require Nad+ Hydrolase Activity, E. J. Brace, Kow Essuman, Xianrong Mao, John Palucki, Yo Sasaki, Jeff Milbrandt, Aaron Diantonio

2020-Current year OA Pubs

SARM1 is the founding member of the TIR-domain family of NAD+ hydrolases and the central executioner of pathological axon degeneration. SARM1-dependent degeneration requires NAD+ hydrolysis. Prior to the discovery that SARM1 is an enzyme, SARM1 was studied as a TIR-domain adaptor protein with non-degenerative signaling roles in innate immunity and invertebrate neurodevelopment, including at the Drosophila neuromuscular junction (NMJ). Here we explore whether the NADase activity of SARM1 also contributes to developmental signaling. We developed transgenic Drosophila lines that express SARM1 variants with normal, deficient, and enhanced NADase activity and tested their function in NMJ development. We find that NMJ …

Harmonizing Model Organism Data In The Alliance Of Genome Resources., Alliance Of Genome Resources Consortium, Anna V. Anagnostopoulos, Susan M. Bello, Judith A. Blake, Olin Blodgett, Carol J. Bult, Karen R. Christie, Mary E. Dolan, Paul Hale, James A. Kadin, Monica S. Mcandrews, Howie Motenko, David R. Shaw, Constance M. Smith, Cynthia L. Smith, Monika Tomczuk, Laurens G. Wilming

Faculty Research 2022

The Alliance of Genome Resources (the Alliance) is a combined effort of 7 knowledgebase projects: Saccharomyces Genome Database, WormBase, FlyBase, Mouse Genome Database, the Zebrafish Information Network, Rat Genome Database, and the Gene Ontology Resource. The Alliance seeks to provide several benefits: better service to the various communities served by these projects; a harmonized view of data for all biomedical researchers, bioinformaticians, clinicians, and students; and a more sustainable infrastructure. The Alliance has harmonized cross-organism data to provide useful comparative views of gene function, gene expression, and human disease relevance. The basis of the comparative views is shared calls of …

Protein Phosphatase 2a Restrains Dlk Signaling To Promote Proper Drosophila Synaptic Development And Mammalian Cortical Neuron Survival, Margaret Hayne, Aaron Diantonio

2020-Current year OA Pubs

Protein phosphatase 2A (PP2A) is a major cellular phosphatase with many protein substrates. As expected for a signaling molecule with many targets, inhibition of PP2A disrupts fundamental aspects of cellular physiology including cell division and survival. In post-mitotic neurons, the microtubule associated protein Tau is a particularly well-studied PP2A substrate as hyperphosphorylation of Tau is a hallmark of Alzheimer's disease. Although many cellular targets are likely altered by loss of PP2A, here we find that activation of a single pathway can explain important aspects of the PP2A loss-of-function phenotype in neurons. We demonstrate that PP2A inhibits activation of the neuronal …

Clinical Utility Of Anti-Mullerian Hormone In Pediatrics, Roopa Kanakatti Shankar, Tazim Dowlut-Mcelroy, Andrew Dauber, Veronica Gomez-Lobo

Pediatrics Faculty Publications

CONTEXT: Anti-Mullerian hormone (AMH) was originally described in the context of sexual differentiation in the male fetus but has gained prominence now as a marker of ovarian reserve and fertility in females. In this mini-review, we offer an updated synopsis on AMH and its clinical utility in pediatric patients.

DESIGN AND RESULTS: A systematic search was undertaken for studies related to the physiology of AMH, normative data, and clinical role in pediatrics. In males, AMH, secreted by Sertoli cells, is found at high levels prenatally and throughout childhood and declines with progression through puberty to overlap with levels in females. …

The Importance Of Protein Context In Spinocerebellar Ataxia Type 3, Sean Luis Johnson

Wayne State University Dissertations

Spinocerebellar Ataxia Type 3 (SCA3) is a member of the family of polyglutamine (polyQ) neurodegenerative disorders that includes Huntington's Disease and several other SCAs. SCA3, the most common dominant ataxia in the world, is caused by polyQ tract expansion in the protein, ataxin-3. How SCA3 occurs and how to treat it remain unresolved issues. The primary culprit of toxicity in all polyQ diseases is the glutamine repeat: its abnormal expansion leads to neuronal dysfunction and death. With that said, there is indisputable evidence that the way polyQ-dependent toxicity presents—areas impacted, cellular processes perturbed—is predicated in large part on regions outside …

The Incidence Of Candidate Binding Sites For Β-Arrestin In Drosophila Neuropeptide Gpcrs, Paul H. Taghert

2020-Current year OA Pubs

To support studies of neuropeptide neuromodulation, I have studied beta-arrestin binding sites (BBS's) by evaluating the incidence of BBS sequences among the C terminal tails (CTs) of each of the 49 Drosophila melanogaster neuropeptide GPCRs. BBS were identified by matches with a prediction derived from structural analysis of rhodopsin:arrestin and vasopressin receptor: arrestin complexes [1]. To increase the rigor of the identification, I determined the conservation of BBS sequences between two long-diverged species D. melanogaster and D. virilis. There is great diversity in the profile of BBS's in this group of GPCRs. I present evidence for conserved BBS's in a …

Adaptable P Body Physical States Differentially Regulate Bicoid Mrna Storage During Early Drosophila Development, M Sankaranarayanan, Ryan J Emenecker, Elise L Wilby, Marcus Jahnel, Irmela R E A Trussina, Matt Wayland, Simon Alberti, Alex S Holehouse, Timothy T Weil

2020-Current year OA Pubs

Ribonucleoprotein condensates can exhibit diverse physical states in vitro and in vivo. Despite considerable progress, the relevance of condensate physical states for in vivo biological function remains limited. Here, we investigated the physical properties of processing bodies (P bodies) and their impact on mRNA storage in mature Drosophila oocytes. We show that the conserved DEAD-box RNA helicase Me31B forms viscous P body condensates, which adopt an arrested physical state. We demonstrate that structurally distinct proteins and protein-protein interactions, together with RNA, regulate the physical properties of P bodies. Using live imaging and in situ hybridization, we show that the arrested …

Mask, The Drosophila Ankyrin Repeat And Kh Domain-Containing Protein, Affects Microtubule Stability, Daniel Martinez, Mingwei Zhu, Jessie J. Guidry, Niles Majeste, Hui Mao, Sarah T. Yanofsky, Xiaolin Tian, Chunlai Wu

School of Medicine Faculty Publications

Proper regulation of microtubule (MT) stability and dynamics is vital for essential cellular processes, including axonal transportation and synaptic growth and remodeling in neurons. In the present study, we demonstrate that the Drosophila ankyrin repeat and KH domain-containing protein Mask negatively affects MT stability in both larval muscles and motor neurons. In larval muscles, loss-of-function of mask increases MT polymer length, and in motor neurons, loss of mask function results in overexpansion of the presynaptic terminal at the larval neuromuscular junctions (NMJs). mask genetically interacts with stathmin (stai), a neuronal modulator of MT stability, in the regulation of axon transportation …

Neurotensin Regulates Proliferation And Stem Cell Function In The Small Intestine In A Nutrient-Dependent Manner, Stephanie A. Rock, Kai Jiang, Yuanyuan Wu, Yajuan Liu, Jing Li, Heidi L. Weiss, Chi Wang, Jianhang Jia, Tianyan Gao, B. Mark Evers

Surgery Faculty Publications

BACKGROUND & AIMS: Intestinal stem cells (ISCs) are sensitive to dietary alterations and nutrient availability. Neurotensin (NT), a gut peptide localized predominantly to the small bowel and released by fat ingestion, stimulates the growth of intestinal mucosa under basal conditions and during periods of nutrient deprivation, suggesting a possible role for NT on ISC function.

METHODS: Leucine-rich repeat-containing G-protein coupled receptor 5-Enhanced Green Fluorescent Protein (Lgr5-EGFP) NT wild type (Nt^+/+) and Lgr5-EGFP NT knockout (Nt^-/-) mice were fed ad libitum or fasted for 48 hours. Small intestine tissue and crypts were examined by gene …

The Developmental Plasticity Of Fruit Fly Vision, John Paul Currea

FIU Electronic Theses and Dissertations

In this dissertation we explore the morphological and neural plasticity underlying vision at different scales—within and between species of Drosophila—to elucidate the role of eye development in the evolution of vision. In chapter 2, we offer a tool to accelerate large-scale research into compound eye morphology, and validate it on the eyes of several insect orders and image media. Then, in chapter 3 we demonstrate the developmental plasticity of eye morphology and neural summation in fruit flies, finding an interesting interplay between the two systems. In chapter 4, we elucidate the role of visual plasticity and neural summation in the …

A Screen For Sleep And Starvation Resistance Identifies A Wake-Promoting Role For The Auxiliary Channel Unc79, Kazuma Murakami, Justin Palermo, Bethany A. Stanhope, Allen G. Gibbs, Alex C. Keene

Life Sciences Faculty Research

The regulation of sleep and metabolism are highly interconnected, and dysregulation of sleep is linked to metabolic diseases that include obesity, diabetes, and heart disease. Furthermore, both acute and long-term changes in diet potently impact sleep duration and quality. To identify novel factors that modulate interactions between sleep and metabolic state, we performed a genetic screen for their roles in regulating sleep duration, starvation resistance, and starvation-dependent modulation of sleep. This screen identified a number of genes with potential roles in regulating sleep, metabolism, or both processes. One such gene encodes the auxiliary ion channel UNC79, which was implicated in …

Molecular And Genetic Studies Of Robo2 Transcriptional Regulation In The Central Nervous System Of Drosophila Melanogaster, Muna Abdal Rahim Abdal Rhida

Graduate Theses and Dissertations

Drosophila Robo2 axon guidance receptor is a member of the evolutionarily conserved Roundabout (Robo) protein family that is involved in directing axons that cross the midline to the other side of the animal body. Robo2 roles mainly depend on two factors: The functional domains of the Robo2 protein, which is extensively studied, and the dynamic transcription of robo2 in various subsets of cells throughout embryogenesis which is not fully understood. Thus, knowing robo2 enhancers that transcriptionally regulate robo2 during embryogenesis is significant. To investigate robo2 potential enhancers, we screened 17 transgenic lines of Drosophila that were generated by Janelia Research …

Conservation And Innovation: Versatile Roles For Lrp4 In Nervous System Development., Alison T. Depew, Timothy J. Mosca

Department of Neuroscience Faculty Papers

As the nervous system develops, connections between neurons must form to enable efficient communication. This complex process of synaptic development requires the coordination of a series of intricate mechanisms between partner neurons to ensure pre- and postsynaptic differentiation. Many of these mechanisms employ transsynaptic signaling via essential secreted factors and cell surface receptors to promote each step of synaptic development. One such cell surface receptor, LRP4, has emerged as a synaptic organizer, playing a critical role in conveying extracellular signals to initiate diverse intracellular events during development. To date, LRP4 is largely known for its role in development of the …

A Conserved Role For Sleep In Supporting Spatial Learning In Drosophila, Krishna Melnattur, Leonie Kirszenblat, Ellen Morgan, Valentin Militchin, Blake Sakran, Denis English, Rushi Patel, Dorothy Chan, Bruno Van Swinderen, Paul J Shaw

2020-Current year OA Pubs

Sleep loss and aging impair hippocampus-dependent Spatial Learning in mammalian systems. Here we use the fly Drosophila melanogaster to investigate the relationship between sleep and Spatial Learning in healthy and impaired flies. The Spatial Learning assay is modeled after the Morris Water Maze. The assay uses a "thermal maze" consisting of a 5 × 5 grid of Peltier plates maintained at 36-37°C and a visual panorama. The first trial begins when a single tile that is associated with a specific visual cue is cooled to 25°C. For subsequent trials, the cold tile is heated, the visual panorama is rotated and …

Machine Learning Approaches Identify Genes Containing Spatial Information From Single-Cell Transcriptomics Data., Phillipe Loher, Nestoras Karathanasis

Computational Medicine Center Faculty Papers

The development of single-cell sequencing technologies has allowed researchers to gain important new knowledge about the expression profile of genes in thousands of individual cells of a model organism or tissue. A common disadvantage of this technology is the loss of the three-dimensional (3-D) structure of the cells. Consequently, the Dialogue on Reverse Engineering Assessment and Methods (DREAM) organized the Single-Cell Transcriptomics Challenge, in which we participated, with the aim to address the following two problems: (a) to identify the top 60, 40, and 20 genes of the Drosophila melanogaster embryo that contain the most spatial information and (b) to …

Molecular Analyses Reveal Consistent Food Web Structure With Elevation In Rainforest Drosophila – Parasitoid Communities, Christopher T. Jeffs, J. Christopher D. Terry, Megan Higgie, Anna Jandová, Hana Konvičková, Joel J. Brown, Chia H. Lue, Michele Schiffer, Eleanor K. O'Brien, Jon Bridle, Jan Hrček, Owen T. Lewis

Research outputs 2014 to 2021

The analysis of interaction networks across spatial environmental gradients is a powerful approach to investigate the responses of communities to global change. Using a combination of DNA metabarcoding and traditional molecular methods we built bipartite Drosophila – parasitoid food webs from six Australian rainforest sites across gradients spanning 850 m in elevation and 5°C in mean temperature. Our cost-effective hierarchical approach to network reconstruction separated the determination of host frequencies from the detection and quantification of interactions. The food webs comprised 5–9 host and 5–11 parasitoid species at each site, and showed a lower incidence of parasitism at high elevation. …