Fig. 1. Chronic stress increased PTEN expression in 5-HT neurons and specific knockout of Pten in 5-HT neurons induced lower depression-like behavior in mice.

a Experimental design of chronic stress. Mice were sacrificed (Sac) 1 day after behavioral tests. FST, force swimming test; SPT, sucrose preference test, TST tail suspension test. b Increase in body weight is prevented during 4-week chronic restraint. c. Immobility time in FST is increased in mice with the 4-week treatment relative to controls. d SPT shows a reduction of the preference in mice with the 4-week treatment. e Immobility time in TST is increased in mice with the 4-week treatment relative to controls. f Western blot shows the elevation of PTEN in midbrain tissues of chronic stress-treated mice. g Immunostaining shows the elevation of PTEN in 5-HT neurons in the dorsal raphe nucleus of mice treated with chronic stress (CS). Scale bar = 100 μm. h Comparison of PTEN immunofluorescence density in 5-HT neurons. i, j Average velocity and ambulatory distance in open field tests are comparable between control and Pten cKO mice. OFT, open field test. k, l Immobility time is reduced in the force swimming test and tail suspension test in Pten cKO mice compared with controls. m SPT shows no difference between control and Pten cKO mice.