Cerebellar granule cells in culture exhibit a ganglioside‐sialidase presumably linked to the plasma membrane
Cerebellar granule cells in culture exhibit a ganglioside‐sialidase presumably linked to the plasma membrane
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培养中的小脑颗粒细胞表现出可能与质膜相关的神经节苷脂唾液酸酶
DOI：
10.1016/0014-5793(91)80012-r
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发表时间：
1991
期刊：
影响因子：
3.5
通讯作者：
G. Tettamanti
中科院分区：
文献类型：
--
作者：
L. Riboni;A. Prinetti;R. Bassi;G. Tettamanti
在培养中分化的小脑颗粒细胞与神经节苷[3H‐Sph]GDla一起孵育，使其插入质膜，通过内吞作用内化并代谢。形成的代谢物包括GMI。GDla脱硅化的产物。培养液中无GMI或其他代谢物存在，而溶酶体装置被氯喹阻断。或GDI a在4°C时内吞作用被阻止，唯一形成的代谢物是GMI。这些结果表明，GDI - 1脱脱酰化既不发生在细胞外也不发生在细胞内，而可能发生在膜水平。用[3H‐Gal]GDlb得到了类似的结果。而[3H - NeuAc]GMI在氯喹存在下或在4°C下均未发生降解。综上所述，小脑颗粒细胞表达viviasidasc，可能位于细胞表面。影响GDIa和GDIb，但不影响GMI。
Cerebellar granule cells differentiated in culture were incubated with ganglioside [3H‐Sph]GDla in order to have it inserted into the plasma membrane, internalized by endocytosis, and metabolized. The metabolites formed included GMI. product of GDla desialosylation. No GMI or other metabolites were present in the incubation medium, whereas with the lysosomal apparatus blocked by chloroquine. or GDI a endocytosis prevented at 4° C, the only metabolite formed was GMI. These results suggest that GDI a desialosylation did not occur either extracellularly or intracellularly but likely, at the membrane level. Similar results were obtained with [3H‐Gal]GDlb. whereas no degradation of [3H‐NeuAc]GMI took place in the presence of chloroquine or at 4°C. In conclusion, cerebellar granule cells expressin vivoa sialidasc, presumably located on the cell surface. that affects GDIa and GDIb but not GMI.