Cahoreau C, Garnier L, Djiane J, Devauchelle G, Cerutti M
Laboratoire de Pathologie Comparée, Institut National de la Recherche Agronomique, CNRS UA 1184, St-Christol-Lez-Alès, France.
FEBS Lett. 1994 Aug 22;350(2-3):230-4. doi: 10.1016/0014-5793(94)00772-1.
The molecular mass of the rabbit prolactin receptor (rbPRLR) deduced from cDNA cloning is 66 kDa. However, the molecular mass of the full-length receptor expressed in the insect Sf9 cells was found to be 94 kDa. In order to explain this discrepancy, we analyzed the possible post-translational modifications of the PRLR. Sf9 cells were infected with recombinant baculoviruses in the presence of tunicamycin, an inhibitor of N-glycosylation. Results showed that an additional approximately 9 kDa of the extracellular domain could be attributed to the N-glycosylation and another additional approximately 20 kDa covalent modification occurred in the cytoplasmic part of the receptor. Western blot analysis, using anti-ubiquitin antibodies, revealed that the rbPRLR was ubiquitinated in its cytoplasmic domain.
从cDNA克隆推导得出的兔催乳素受体（rbPRLR）的分子量为66 kDa。然而，在昆虫Sf9细胞中表达的全长受体的分子量为94 kDa。为了解释这种差异，我们分析了PRLR可能的翻译后修饰。在衣霉素（一种N-糖基化抑制剂）存在的情况下，用重组杆状病毒感染Sf9细胞。结果表明，细胞外结构域额外增加的约9 kDa可归因于N-糖基化，并且在受体的细胞质部分发生了另外约20 kDa的共价修饰。使用抗泛素抗体的蛋白质免疫印迹分析表明，rbPRLR在其细胞质结构域被泛素化。
