Takahashi K P, Higashi Y, Uchimoto T, Hasuma T, Yamamoto N, Morisawa S, Inoue A
Department of Anatomy, Osaka City University Medical School, Japan.
Histochemistry. 1990;93(4):381-4. doi: 10.1007/BF00315854.
S1 proteins are present in the nuclear structures sensitive to DNases and RNase. To examine localization of these proteins, an antibody was raised in a rabbit. Indirect immunofluorescence staining revealed that S1 proteins located in the extranucleolar nuclear regions of quiescent myocardial and cerebellar cells as well as actively duplicating mouse 3T3 fibroblasts. They located in euchromatin regions of thymus lymphocytes, with a characteristic aster-like immunofluorescence pattern, and on the border of condensed chromatin areas by deposition of immunogold particles in ultrathin sections of thymus. Thus, S1 proteins may be in a nuclear function assigned to the border of heterochromatin areas, and other than synthesis of DNA or of ribosomal RNA. Possible involvement of S1 proteins in the extranucleolar RNA synthesis is discussed.
S1蛋白存在于对脱氧核糖核酸酶和核糖核酸酶敏感的核结构中。为检测这些蛋白的定位，用兔子制备了抗体。间接免疫荧光染色显示，S1蛋白位于静止心肌细胞和小脑细胞的核仁外核区域以及活跃增殖的小鼠3T3成纤维细胞中。它们位于胸腺淋巴细胞的常染色质区域，具有特征性的星状免疫荧光模式，并且在胸腺超薄切片中通过免疫金颗粒沉积位于浓缩染色质区域的边界。因此，S1蛋白可能具有分配给异染色质区域边界的核功能，且与DNA或核糖体RNA的合成无关。文中讨论了S1蛋白可能参与核仁外RNA合成的情况。
