peroxiredoxin-1; thioredoxin peroxidase 2; thioredoxin-dependent peroxide reductase 2; proliferation-associated gene protein; PAG; natural killer cell-enhancing factor A; NKEF-A (PRDX1, PAGA, PAGB, TDPX2)

^[1]^[2]^[3]

Function

role in redox regulation of the cell
reduces peroxides with reducing equivalents provided through the thioredoxin system but not from glutaredoxin
may play a role in eliminating peroxides generated during metabolism
might participate in signaling cascades of growth factors & tumor necrosis factor-alpha by regulating intracellular H2O2
phosphorylated on Thr-90 during the M-phase, which leads to a > 80% decrease in enzymatic activity
may form heterodimers with AOP2
active site is the redox-active Cys-52 oxidized to Cys-SOH
Cys-SOH rapidly reacts with Cys-173-SH of the other subunit to form an intermolecular disulfide with a concomitant homodimer formation
the enzyme may be subsequently regenerated by reduction of the disulfide by thioredoxin
inactivated upon oxidative stress by overoxidation of Cys-52 to Cys-SO2H & Cys-SO3H
Cys-SO2H is retroreduced to Cys-SOH after removal of H2O2, while Cys-SO3H may be irreversibly oxidized

2 R'-SH + ROOH = R'-S-S-R' + H2O + ROH

constitutively expressed in most human cells
induced to higher levels upon serum stimulation in untransformed & transformed cells