Department of Molecular and Experimental Medicine, The Scripps Research Institute La Jolla, California 92037, USA.
Blood Cells Mol Dis. 2010 Oct 15;45(3):227-32. doi: 10.1016/j.bcmd.2010.07.014. Epub 2010 Aug 30.
The antioxidant enzyme manganese superoxide dismutase (SOD2) serves as the primary defense against mitochondrial superoxide. Impaired SOD2 activity in murine hematopoietic cells affects erythroid development, resulting in anemia characterized by intra-mitochondrial iron deposition, reticulocytosis and shortened red cell life span. Gene expression profiling of normal and SOD2 deficient erythroblasts identified the Parkinson's disease locus DJ-1 (Park7) as a differentially expressed transcript. To investigate the role of DJ-1 in hematopoietic cell development and protection against oxidative stress caused by Sod2 loss, we evaluated red cell parameters, reticulocyte count, red cell turnover and reactive oxygen species production in DJ-1 knockout animals and chimeric animals lacking both SOD2 and DJ-1 in hematopoietic cells generated by fetal liver transplantation. We also investigated DJ-1 protein expression in primary murine erythroid and erythroleukemia cells (MEL). Loss of DJ-1 exacerbates the phenotype of SOD2 deficiency, increasing reticulocyte count and decreasing red cell survival. Using MEL cells, we show that DJ-1 is up-regulated at the protein level during erythroid differentiation. These results indicate that DJ-1 plays a physiologic role in protection of erythroid cells from oxidant damage, a function unmasked in the context of oxidative stress.
抗氧化酶锰超氧化物歧化酶 (SOD2) 是抵抗线粒体超氧自由基的主要防御机制。小鼠造血细胞中 SOD2 活性受损会影响红细胞的发育,导致以线粒体铁沉积、网织红细胞增多和红细胞寿命缩短为特征的贫血。对正常和 SOD2 缺陷的红细胞进行基因表达谱分析,确定帕金森病基因 DJ-1(Park7)为差异表达的转录本。为了研究 DJ-1 在造血细胞发育中的作用以及对 Sod2 缺失引起的氧化应激的保护作用,我们评估了 DJ-1 敲除动物和通过胎肝移植生成的造血细胞中缺乏 SOD2 和 DJ-1 的嵌合动物的红细胞参数、网织红细胞计数、红细胞周转率和活性氧产生。我们还研究了 DJ-1 蛋白在原代小鼠红细胞和红白血病细胞 (MEL) 中的表达。DJ-1 的缺失加剧了 SOD2 缺乏的表型,增加了网织红细胞计数,降低了红细胞的存活率。使用 MEL 细胞,我们表明 DJ-1 在红细胞分化过程中在蛋白质水平上上调。这些结果表明,DJ-1 在保护红细胞免受氧化剂损伤方面发挥着生理作用,这一功能在氧化应激的情况下显现出来。