S19 ribosomal protein dimer augments metal-induced apoptosis in a mouse fibroblastic cell line by Ligation of the c5a receptor
S19 ribosomal protein dimer augments metal-induced apoptosis in a mouse fibroblastic cell line by Ligation of the c5a receptor
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DOI：
10.1002/jcb.20318
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发表时间：
2005-02-15
影响因子：
4
通讯作者：
Yamamoto, T
中科院分区：
文献类型：
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作者：
Nishiura, H;Tanase, S;Yamamoto, T
为了分析S19核糖体蛋白（RP S19）在细胞凋亡中的作用，将小鼠NIH3T3转染血凝素肽标记（HA）野生型人RP S19或抗转谷氨酰胺酶催化交联二聚化的突变体（GIn137Asn）。转染突变体HA-RP S19抑制锰（II） （Mn II）诱导的细胞凋亡，而野生型HA-RP S19增强细胞凋亡和模拟转染没有影响。在细胞凋亡过程中观察到野生型HA-RP S19二聚体的释放，而突变型HA-RP S19未被释放。转染突变体HA-RP S19的细胞凋亡率降低，通过添加细胞外野生型RP S19二聚体克服。转染人HA-RP - S19和模拟转染的细胞凋亡率在培养基中存在抗rp - S19抗体的情况下降低到40%左右。免疫荧光染色和荧光活化细胞分选（FACS）分析显示，与磷脂酰丝氨酸暴露同时发生的凋亡过程中，交联RP S19二聚体受体C5a受体的细胞表面表达增加。C5a受体基因的表达也增加了两倍。在转染和对照细胞系中，抗小鼠C5a受体单克隆抗体或肽C5a受体拮抗剂的存在也降低了细胞凋亡率。这些结果表明，在Mn ii诱导的小鼠成纤维细胞系凋亡过程中，存在RP S19二聚体和C5a受体介导的自分泌型增强机制。与RP S19二聚体相反，C5a实际上抑制了细胞凋亡，这表明通过C5a受体的信号传导取决于结合的配体。(C) 2004 Wiley-Liss, Inc。
To analyze the role of S19 ribosomal protein (RP S19) in apoptosis, murine NIH3T3 were transfected with either hemagglutinin peptide-tagged (HA) wild-type human RP S19 or a mutant (GIn137Asn) that is resistant to transglutaminase-catalyzed cross-linked-dimerization. Transfection with the mutant HA-RP S19 inhibited manganese (II) (Mn II)-induced apoptosis whereas the wild-type HA-RP S19 augmented apoptosis and a mock transfection had no effect. Release of the wild-type HA-RP S19 dimer but not the mutant HA-RP S19 was observed during the apoptosis. The reduced rate of apoptosis of the cells transfected with the mutant HA-RP S19 was overcome by addition of extracellular wild-type RP S19 dimer. The apoptosis rates in cells transfected with either form of human HA-RP S19 and in mock transfectants were reduced to about 40% by the presence of anti-RP S19 antibody in the culture medium. Immunofluorescence staining and fluorescence-activated cell sorting (FACS) analysis showed that the cell surface expression of the receptor for cross-linked RP S19 dimer, C5a receptor, increased during apoptosis, concomitant with phosphatidylserine exposure. The expression of the C5a receptor gene also increased twofold. Apoptosis rates in the transfected and control cell lines were also reduced by the presence of an anti-mouse C5a receptor monoclonal antibody or of a peptide C5a receptor antagonist. These results indicated the presence of an RP S19 dimer- and C5a receptor-mediated autocrine-type augmentation mechanism during Mn II-induced apoptosis in the mouse fibroblastic cell line. In contrast to the RP S19 dimer, C5a actually inhibited apoptosis, suggesting that signaling through the C5a receptor varies depending on the ligand bound. (C) 2004 Wiley-Liss, Inc.