Maraldi N M, Zini N, Squarzoni S, Del Coco R, Sabatelli P, Manzoli F A
Istituto di Citomorfologia Normale e Patologica CNR, Istituto Rizzoli, Bologna, Italy.
J Histochem Cytochem. 1992 Sep;40(9):1383-92. doi: 10.1177/40.9.1506675.
The presence of phospholipids within the interphase nucleus and in isolated chromatin, previously demonstrated by analytical biochemical methods, has been only rarely documented by cytochemical procedures, especially at the ultrastructural level. By means of a gold-conjugated phospholipase technique, we investigated the fine localization of endogenous phospholipids in the different nuclear domains in rat pancreas and in cell cultures. To reduce possible removal or displacement of phospholipids, different specimen preparation procedures such as cryofixation, cryosectioning, and freeze-fracturing were utilized. Apart from slight differences in efficiency among these methods, phospholipids have been cytochemically identified in the same nuclear domains: the interchromatin granules and fibers and the dense fibrillar component of the nucleolus. These results suggest that the phospholipids are an actual nuclear component, not randomly distributed in the nucleoplasm but mainly localized in the nuclear domains involved in the synthesis, maturation, and transport of ribonucleoproteins.
此前通过分析生化方法已证实，间期细胞核和分离染色质中存在磷脂，但通过细胞化学方法进行记录的情况却很少，尤其是在超微结构水平上。我们借助金偶联磷脂酶技术，研究了大鼠胰腺不同核区域以及细胞培养物中内源性磷脂的精细定位。为减少磷脂可能的去除或移位，我们采用了不同的标本制备程序，如冷冻固定、冷冻切片和冷冻断裂。除了这些方法在效率上存在细微差异外，在相同的核区域已通过细胞化学方法鉴定出磷脂：染色质间颗粒和纤维以及核仁的致密纤维成分。这些结果表明，磷脂是细胞核的实际组成成分，并非随机分布于核质中，而是主要定位于参与核糖核蛋白合成、成熟和运输的核区域。
