Wong Chi-Ming, Marcocci Lucia, Das Dividutta, Wang Xinhong, Luo Haibei, Zungu-Edmondson Makhosazane, Suzuki Yuichiro J
Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC 20057, USA.
Department of Biochemical Sciences "A. Rossi Fanelli," Sapienza University of Rome, Rome, Italy.
Free Radic Biol Med. 2013 Dec;65:1126-1133. doi: 10.1016/j.freeradbiomed.2013.09.005. Epub 2013 Sep 14.
Ligand/receptor stimulation of cells promotes protein carbonylation that is followed by the decarbonylation process, which might involve thiol-dependent reduction (C.M. Wong et al., Circ. Res. 102:301-318; 2008). This study further investigated the properties of this protein decarbonylation mechanism. We found that the thiol-mediated reduction of protein carbonyls is dependent on heat-labile biologic components. Cysteine and glutathione were efficient substrates for decarbonylation. Thiols decreased the protein carbonyl content, as detected by 2,4-dinitrophenylhydrazine, but not the levels of malondialdehyde or 4-hydroxynonenal protein adducts. Mass spectrometry identified proteins that undergo thiol-dependent decarbonylation, which include peroxiredoxins. Peroxiredoxin-2 and -6 were carbonylated and subsequently decarbonylated in response to the ligand/receptor stimulation of cells. siRNA knockdown of glutaredoxin inhibited the decarbonylation of peroxiredoxin. These results strengthen the concept that thiol-dependent decarbonylation defines the kinetics of protein carbonylation signaling.
细胞的配体/受体刺激会促进蛋白质羰基化，随后发生脱羰基化过程，这可能涉及硫醇依赖性还原（C.M. Wong等人，《循环研究》102:301 - 318；2008年）。本研究进一步探究了这种蛋白质脱羰基化机制的特性。我们发现硫醇介导的蛋白质羰基还原依赖于热不稳定的生物成分。半胱氨酸和谷胱甘肽是脱羰基化的有效底物。硫醇降低了用2,4 - 二硝基苯肼检测到的蛋白质羰基含量，但不影响丙二醛或4 - 羟基壬烯醛蛋白质加合物的水平。质谱鉴定了经历硫醇依赖性脱羰基化的蛋白质，其中包括过氧化物酶。过氧化物酶2和 - 6在细胞的配体/受体刺激下发生羰基化，随后又发生脱羰基化。谷氧还蛋白的siRNA敲低抑制了过氧化物酶的脱羰基化。这些结果强化了硫醇依赖性脱羰基化决定蛋白质羰基化信号动力学的概念。
