Freund J N
Institut National de la Santé et de la Recherche Médicale, Unité 61, France.
Cell Mol Biol (Noisy-le-grand). 1992 Nov;38(7):713-8.
The 225 kDa precursor of intestinal lactase-phlorizin hydrolase (LPH) consists of four tandemly-organized homologous domains flanked by a signal peptide at the N-end and by a transmembrane anchor at the C-end of the polypeptide chain. While the mature LPH of 130 kDa has already been shown to originate from the C-half of the precursor, no protein deriving from the N-half has been identified so far. Using monospecific antibodies raised against the mature LPH or against a recombinant protein containing the sequence of the N-end of the LPH precursor, we have searched for co-translated protein(s) of LPH in enterocytes and in the intestinal lumen of suckling rats. Since no additional protein to LPH was revealed by these antibodies, it is suggested that the polypeptide chain corresponding to the N-half of the LPH precursor undergoes rapid turnover.
肠乳糖酶-根皮苷水解酶（LPH）的225 kDa前体由四个串联排列的同源结构域组成，在多肽链的N端有一个信号肽，C端有一个跨膜锚定结构。虽然130 kDa的成熟LPH已被证明起源于前体的C端一半，但迄今为止尚未鉴定出源自N端一半的蛋白质。我们使用针对成熟LPH或含有LPH前体N端序列的重组蛋白产生的单特异性抗体，在哺乳大鼠的肠上皮细胞和肠腔中寻找LPH的共翻译蛋白。由于这些抗体未发现除LPH之外的其他蛋白质，提示与LPH前体N端一半相对应的多肽链周转迅速。
