Search bioRxiv⌕ Search

bioRxiv · 10.1101/2025.02.27.640021

MyoRep: a novel reporter system to detect early muscle atrophy in vitro and in vivo

Abstract

Muscle atrophy occurs during physiological (i.e., fasting, aging) and pathological (i.e., amyotrophic lateral sclerosis, cancer) conditions and anticipates death. Since not all patients will undergo muscle wasting, it would be highly useful to identify them soon to intervene early. We have studied the promoters/enhancers of a subset of atrophy-related genes or atrogenes upregulated in muscles of rodents during various kinds of atrophy (i.e., disuse, diabetes, cancer, fasting, uremia) for their ability to induce early atrophy. Comparing their upstream non-coding regions, using as backbone MuRF1 promoter (one of the earliest muscle-specific genes induced by wasting), we cloned various promoters upstream of a doubled reporter system (FLuciferase/tdTomato). Through in vitro and in vivo studies in mice subjected to denervation or cancer injection, we selected a sequence (i.e., MyoRep) able to predict atrophy upon cut of the sciatic nerve or cancer. In vivo imaging of MyoRep mice emit a bioluminescent signal earlier than muscle loss. Importantly, MyoRep was unable to sense atrophy during fasting or physiological variations following the circadian rhythms. Since MyoRep can discriminate muscle loss due to pathological conditions from physiological ones anticipating wasting, it represents an unprecedented tool to predict it early in various diseases with local or systemic atrophy.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Re Cecconi, A. D., Rizzi, N., Barone, M., Palo, F., Lunardi, M., Forti, M., Maggi, A., Ciana, P., Terribile, G., Chiappa, M., Zentilin, L., Piccirillo, R.. 2025-03-01. MyoRep: a novel reporter system to detect early muscle atrophy in vitro and in vivo. https://doi.org/10.1101/2025.02.27.640021

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

KEEP EXPLORING

Related preprints

Generation of a transgenic cephalopod

Coleoid cephalopods (cuttlefish, octopus, and squid) are marine mollusks with elaborate nervous systems that support a diverse repertoire of complex behaviors. These include the neural control of the color, pattern, and texture of the skin, facilitating both adaptive camouflage and innate patterning that may reflect internal state. The development of transgenic cephalopods expressing fluorescent proteins, optogenetic actuators, and reporters of neural activity would contribute a new and important technology to cephalopod biology. The generation of transgenic cephalopods, however, has remained a major challenge. Here, we report the development of stable transgenic dwarf cuttlefish (Ascarosepion bandense) expressing ubiquitous nuclear-localized mScarlet, a red fluorescent protein. We evaluated multiple strategies for transgenesis, and established cuttlefish lines using both CRISPR and the transposons Sleeping Beauty and Minos. The stable expression of transgenes enabled live imaging of cell dynamics during embryonic development. The Minos transposon emerged as the most efficient transgenesis strategy and is adaptable to promoters and transgenes of choice. These strategies now enable the generation of diverse genetic tools for mechanistic studies of cephalopod biology.

genetics↗

Large language model-based bibliometric evaluation of population descriptors in human genetics

As the use of population descriptors such as race, ethnicity, and ancestry have become increasingly common in modern genetics research, there have been growing calls to critically examine their use. Most notably, in 2023, the National Academies of Science, Engineering, and Medicine (NASEM) published a report titled Using Population Descriptors in Genetics and Genomics Research: A New Framework for an Evolving Field, which included eight specific and actionable recommendations for researchers to implement the ethical and accurate use of population descriptors in genetic research. Here, we use the 2023 NASEM report as a benchmark to analyze the use of population descriptors in genome-wide association studies (GWAS). We develop a general toolkit for large language model-based bibliometrics, operationalize the report's recommendations into an evaluation framework, and apply this framework to evaluate all 4,007 papers from the GWAS Catalog published between 2007 and 2025 with full text available on PubMedCentral. We find significant improvements in adherence to NASEM report recommendations over time. However, most improvements predate the publication of the NASEM report itself, suggesting the report functioned primarily as a synthesis of existing best practices rather than a catalyst for change. We conclude by highlighting opportunities for growth in the field of human genetics.

genetics↗

Mitigating biases of rescaling in forward-in-time population genetic simulations

Forward-in-time population genetic simulations are widely used in evolutionary analyses, but simulating large populations and long genomic regions remains computationally demanding. To reduce this cost, parameter rescaling is widely employed, in which the original evolutionary process is approximated by one with a smaller population size and fewer generations. Recently, several studies using the SLiM simulator have raised concerns about the accuracy of this rescaling approach. In this study, we show that many of the biases reported in these studies can be mitigated by using a different simulation algorithm. These results reveal that the accuracy of parameter rescaling depends on how well the simulation algorithm preserves diffusion-limit properties under rescaling.

genetics↗