Ruby-throated hummingbirds suppress ATP demand to save energy during torpor

American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 2026 Open access

Read full text
Authors: Amalie J. Hutchinson, Cory Robinson Elowe, James F. Staples, Christopher G. Guglielmo
DOI: 10.1152/ajpregu.00071.2026
Cited by: 1
References: 52

Abstract

The cellular mechanisms that underlie hummingbird torpor are only beginning to be studied. We are the first to report two ATP-demand pathways downregulated in torpid ruby-throated hummingbirds. We characterized SERCA and Na + /K + ATPase activity in normothermia and torpor. SERCA activity was 10–13× higher than in songbirds. Sarcolipin was more phosphorylated in torpor, reducing heat production, and Na + /K + ATPase activity fell 43%. These shifts lower ATP demand and conserve energy during torpor.

Fields of Study & Subjects

Bat Biology and Ecology Studies Physiological and biochemical adaptations Thermal Regulation in Medicine

Publication details

Journal / source
American Journal of Physiology-Regulatory, Integrative and Comparative Physiology
Publisher
American Physiological Society
Volume
331
Issue
1
Pages
R53–R62
Publication date
1 June 2026
Language
EN