The direct effect of this gene may be to increase the metabolism rate in the mouse's body and thus increase the physical fitness and endurance of the mouse. By injecting the gene, scientists could greatly increase the metabolism rate of mice, allowing them to better cope with long-term running and exercise without feeling tired or exhausted. This gene may also affect other physiological systems in mice, such as heart and lung function and muscle system, so that they can better carry out long-term exercise and running.