Bergsagel P L, Timblin C R, Eckhardt L, Laskov R, Kuehl W M
Navy Medical Oncology Branch, National Cancer Institute, Bethesda, Maryland 20889-5105.
Oncogene. 1992 Oct;7(10):2059-64.
Using a subtractive cDNA approach we have identified a gene, PC326, expressed in 13 of 14 murine plasmacytoma cell lines, but not in any B- or pre-B-lymphoma cell lines. It expresses 4.6-kb and 5.2-kb mRNAs that encode a 747 amino acid protein containing two highly acidic domains flanking a novel, moderately acidic 20 amino acid sequence that is repeated 7.5 times. Sequence comparison identifies an additional 43 amino acid domain that is homologous to a repeated sequence found in the members of the beta-transducin gene family. The PC326 mRNA is detectable in testis but in no other murine tissues, including plasma cells induced by lipopolysaccharide stimulation of splenocytes. Somatic cell hybrids derived from plasmacytomas and fibroblast or T-cell lines have a fibroblastic or T-cell phenotype respectively. Unlike B-cell-specific genes (e.g. immunoglobulin), the expression of which is extinguished in these hybrids, PC326 mRNA appears to be irreversibly turned on in these hybrids. Since PC326 is not expressed in normal plasma cells, it appears that its expression is a cause or consequence of the tumorigenic process that generates murine plasmacytomas.
利用消减cDNA方法，我们鉴定出一个基因PC326，它在14个小鼠浆细胞瘤细胞系中的13个中表达，但在任何B或前B淋巴瘤细胞系中均不表达。它表达4.6kb和5.2kb的mRNA，编码一种747个氨基酸的蛋白质，该蛋白质含有两个高度酸性结构域，两侧是一个新的、中等酸性的20个氨基酸序列，该序列重复7.5次。序列比较确定了一个额外的43个氨基酸结构域，它与β-转导蛋白基因家族成员中发现的一个重复序列同源。PC326 mRNA在睾丸中可检测到，但在其他小鼠组织中均未检测到，包括脂多糖刺激脾细胞诱导产生的浆细胞。源自浆细胞瘤与成纤维细胞或T细胞系的体细胞杂种分别具有成纤维细胞或T细胞表型。与B细胞特异性基因（如免疫球蛋白）不同，其在这些杂种中表达消失，而PC326 mRNA在这些杂种中似乎不可逆地开启。由于PC326在正常浆细胞中不表达，其表达似乎是产生小鼠浆细胞瘤的致瘤过程的原因或结果。
