Testis developmental related gene 1 (TDRG1) promotes autophagy through p110β/Rab5/Vps34 (PI3‐Kinase Class III) activation. A, Protein expression of TDRG1, p110β, Rab5‐GTP, Rab5, Beclin‐1, Atg‐14L and Vps34 in TCam‐2 cells was measured by Western blotting at 72 h after transfection with constructs to overexpress of knockdown TDRG1. GAPDH served as the internal control. B, Vps34 activity was measured by analysing PI(3)P production by the ELISA described in Section 2. C, Protein expression of TDRG1, p110β, Rab5‐GTP and LC3‐II (untreated or treated with 200 nmol/L Baf A1 for 6 h) was measured by protein gel blotting 72 h after transfection with siRNA to block the expression of p110β and Rab5 or treatment with 3‐MA (autophagy inhibitor). GAPDH served as the internal control. D, Vps34 activity was measured by analysing PI(3)P production by the ELISA described in Section 2. (Data from three independent experiments, error bars represent SD, *P < .05, **P < .01, ***P < .001)