Disease & heat resistance

Altered Thermogenic and Behavioral Responses to Cold Stress in Mice Carrying a Camel-Derived Nrap Mutation

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Abstract

Adaptation to extreme environments requires tightly coordinated physiological and behavioral responses, many of which are mediated by cardiac and skeletal muscle function. The camel, a species renowned for exceptional heat and cold tolerance as well as metabolic resilience, possesses unique genetic features that likely contribute to its environmental adaptability. However, directly validating the functional impact of camel-specific genetic variants in camels themselves is challenging due to ethical and logistical constraints. Therefore, mouse models represent a powerful approach for experimentally dissecting camel-derived adaptive gene functions. Nebulin-related anchoring protein (Nrap) is a myofibrillar protein involved in force transmission and muscle structural stability. Building upon prior work, the present study investigates the functional consequences of a camel-specific variant, Nrap c.255ins78, focusing on its roles in thermoregulation, locomotor activity, and tissue-specific expression. Wild-type (WT) and Nrap c.255ins78 mice were subjected to cold exposure (4 °C) for up to 12 hours. Physiological traits and behavioral responses were quantified, and statistical significance was determined using two-way analysis of variance (ANOVA) followed by Bonferroni's post-hoc test to compare genotypes and time points. During cold exposure, Nrap c.255ins78 mice maintained their rectal temperature significantly better than WT mice, indicating superior cold-induced thermoregulation. At room temperature, mutant mice displayed substantially elevated locomotor activity, characterized by increased distance traveled and reduced freezing time. RT-PCR analysis revealed markedly higher Nrap expression in cardiac muscle relative to non-muscle tissues, suggesting that the Nrap c.255ins78 variant may alter cardiac functional output to support systemic metabolic demands during thermal stress. In summary, our findings demonstrate that the Nrap c.255ins78 mutation strengthens thermal homeostasis during cold exposure while enhancing locomotor activity under normothermic conditions. These results offer new insight into camel-inspired environmental adaptation mechanisms and highlight the value of transgenic mouse systems for validating adaptive genes from extreme-environment species.

Keywords: 2026

How to Cite:

Yee, N., Lee, S. & Kim, K., (2026) “Altered Thermogenic and Behavioral Responses to Cold Stress in Mice Carrying a Camel-Derived Nrap Mutation”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286313. doi: https://doi.org/10.31274/wcgalp.23919

Rights: 1