bioRxiv Science⌕ Search

bioRxiv · 10.1101/239459

MAPLE: a Modular Automated Platform for Large-scale Experiments, a low-cost robot for integrated animal-handling and phenotyping

Abstract

Genetic model system animals have significant scientific value in part because of large-scale experiments like screens, but performing such experiments over long time periods by hand is arduous and risks errors. Thus the field is poised to benefit from automation, just as molecular biology did from liquid-handling robots. We developed a Modular Automated Platform for Large-scale Experiments (MAPLE), a Drosophila-handling robot capable of conducting lab tasks and experiments. We demonstrate MAPLEs ability to accelerate the collection of virgin female flies (a pervasive experimental chore in fly genetics) and assist high-throughput phenotyping assays. Using MAPLE to autonomously run a novel social interaction experiment, we found that 1) pairs of flies exhibit persistent idiosyncrasies in affiliative behavior, 2) these dyad-specific interactions require olfactory and visual cues, and 3) social interaction network structure is topologically stable over time. These diverse examples demonstrate MAPLEs versatility as a general platform for conducting fly science automatically.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Alisch, T., Crall, J. D., Zucker, D., de Bivort, B. L.. 2017-12-24. MAPLE: a Modular Automated Platform for Large-scale Experiments, a low-cost robot for integrated animal-handling and phenotyping. https://doi.org/10.1101/239459

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Cascaded Dual-Targeting (WTW/TAT) Liposomes Delivery DOX for Precision Glioblastoma Treatment

Glioblastoma (GBM) remains difficult to treat because the blood-brain barrier (BBB) and blood-tumor barrier (BTB) severely limit drug transport into tumor tissue. To address these delivery constraints, we developed a dual-targeted liposomal nanoplatform (WT-LIP) that integrates a WTW dual-targeting peptide to promote receptor-mediated BBB transcytosis and specificity to GBM and a TAT peptide to enhance post-barrier penetration and tumor-cell uptake, enabling sequential barrier crossing and GBM targeting. DOX@WT-LIP efficiently encapsulated doxorubicin (DOX) and increased endothelial transport in vitro, achieving a permeated dose of 60.74 {+/-} 2.14% at 480 min, while producing deeper transendothelial penetration and greater downstream tumor killing in a BBB/GBM co-culture. In orthotopic U251-luc models, DiD-labeled WT-LIP showed enhanced brain/tumor accumulation (G/B = 2.16 {+/-} 0.06), and DOX@WT-LIP markedly suppressed tumor growth (74.92% inhibition), improved survival, and exhibited comparatively reduced systemic toxicity. This work highlights a ligand-guided strategy that couples efficient BBB transport with tumor-selective delivery to improve GBM chemotherapy.

bioengineering↗

Biological Signaling Pathways Associated with Late Tendon Development in Chicken Embryos and Their Dependence on Mechanical Stimulation

During embryonic and neonatal development, tendons exhibit rapid changes in mechanics and structure, including increases in collagen content, crosslinking, and fibril length. These functional and structural changes are partly dependent on mechanical stimulation. However, the specific mechanobiological mechanisms driving these changes remain poorly understood. The objective of this study was to identify the potential biological mechanisms and pathways driving tendon maturation into load-bearing materials using an embryonic chick model. Using bulk RNA sequencing, gene set enrichment analysis, and transcription factor analysis, we produced a transcriptomic profile of chick hindlimb tendons during late embryonic development (E16, E18, and E20) and tendons from rigid and flaccid paralysis-treated embryos. Additionally, we assessed the results from two differential expression analysis models to improve the replicability of our findings. Our results suggest that the largest transcriptomic response occurs between embryonic day 16 and 20, and that among paralysis conditions, rigid paralysis produces the greatest effect relative to controls. Across development, we found positive enrichment in processes related to mechanotransduction, extracellular matrix remodeling, cell adhesion, and contractility, and identified candidate pathways upregulated with development, including TGF-{beta}, PI3K-AKT-mTOR, Hippo, circadian rhythm, and focal adhesion signaling. In paralysis-treated embryos, our data suggest impairment in extracellular matrix remodeling and mechanotransduction events. Specifically, we found that both modes of paralysis are associated with a cellular stress response and downregulation of WNT signaling. Together, our findings identify candidate mechanotransduction pathways that are associated with late tendon maturation and altered by paralysis, which may inform tendon tissue engineering and regenerative approaches.

bioengineering↗

Transferrin receptor binding valency determines the circulating half-life and weight-loss efficacy of Fc-FGF21 in TfR-humanized mice

Fibroblast growth factor 21 (FGF21) is a promising metabolic hormone with potent anti-obesity effects. It acts in both the central nervous system and peripheral tissues to exert its metabolic benefits. Because its receptors are expressed at low levels in the brain, we hypothesized that enhanced transport across the blood-brain barrier (BBB) would improve its efficacy. To achieve this, FGF21 was fused to Fc(TV35), an engineered Fc fragment that binds the human transferrin receptor (hTfR), to generate Fc(TV35)-FGF21. Fc(TV35)-FGF21 does not bind to mouse TfR, so it produced weight-loss effects in wild-type diet-induced obese mice comparable to those of Fc-FGF21. However, it failed to induce weight loss in homozygous hTfR-humanized mice because of a markedly shortened circulating half-life. Converting Fc(TV35)-FGF21 from a homodimer to a bispecific Fc format with a single hTfR-binding arm partially restored the circulating half-life and weight-loss efficacy. Reducing mouse hTfR zygosity from homozygous to heterozygous did not substantially improve the engineered protein's half-life or weight-loss effect. Taken together, our findings suggest that sustained systemic exposure is a major determinant of FGF21's weight-loss efficacy and that hTfR engagement can shorten its systemic half-life and compromise its therapeutic activity. These results highlight an important design limitation of TfR-based brain vehicles, especially for delivering metabolic hormones with low-abundance CNS receptor targets. As a result, further optimization of shuttle formats to minimize systemic clearance while crossing the BBB is needed for metabolic hormones.

bioengineering↗