ACO2 and depressive symptom measurement: Among identified phosphoproteins in this study, ATP5A1, HSPD1, DPYSL2, ENO3, ACO2, CNP, HSP90AB1, ACTBL2, TUBA, TUBB and DDX were also found in dorsolateral prefrontal cortex of major depressive disorder patients [1], which further supports the contention that phosphoproteins contribute to depression pathogenesis.