2024 Volume 6 Pages 12-
The microgravity (μ-g) environment during spaceflight can cause severe acute bone loss. To identify gravity-response proteins involved in bone metabolism, we analyzed the proteome of the femur and mandible collected from spaceflight mice raised in a μ-g or artificial 1-gravity (A1-g) environment on the International Space Station in orbit. The bone mass of the femur diaphysis decreased in response to gravity unloading, whereas that of the mandible remained unchanged due to mastication stimuli. Collective evaluation of the dataset of the proteome of the femur and mandible obtained by data-independent acquisition mass spectrometry (DIA-MS) identified the bone proteins that were altered by the μ-g environment and involved in bone loss.