Dale B A, Ling S Y
Biochemistry. 1979 Aug 7;18(16):3539-46. doi: 10.1021/bi00583a016.
The fully differentiated anucleate cells of the stratum corneum of newborn rat epidermis contain a cationic protein called stratum corneum basic protein (SCBP). This protein has a molecular weight (49 000) and an amino acid composition similar to a protein extracted from the less differentiated cell layers of the epidermis. Pulse--chase experiments with radiolabeled histidine were undertaken to test the possiblity that SCBP is derived from a preexisting protein. A protein of 52 000 daltons is rapidly but transiently labeled in extracts of the less differentiated cell layers. As the amount of label in the 52 000-dalton protein decreases, an increase in radiolabel is observed in extracts of the fully differentiated cells. This label is found in SCBP, a protein of lower molecular weight (49 000) than that initially labeled. These proteins are immunologically related and both are resistant to cyanogen bromide cleavage. They differ in apparent molecular weight on sodium dodecyl sulfate--polyacrylamide gels and in their net charge. The results are consistent with the conversion of a precursor protein into SCBP.
新生大鼠表皮角质层完全分化的无核细胞含有一种名为角质层碱性蛋白（SCBP）的阳离子蛋白。这种蛋白质的分子量（49000）和氨基酸组成与从表皮分化程度较低的细胞层中提取的一种蛋白质相似。采用放射性标记的组氨酸进行脉冲追踪实验，以检验SCBP是否源自一种预先存在的蛋白质。在分化程度较低的细胞层提取物中，一种52000道尔顿的蛋白质被迅速但短暂地标记。随着52000道尔顿蛋白质中标记量的减少，在完全分化细胞的提取物中观察到放射性标记增加。这种标记存在于SCBP中，SCBP是一种分子量（49000）比最初标记的蛋白质低的蛋白质。这些蛋白质在免疫学上相关，并且都对溴化氰裂解具有抗性。它们在十二烷基硫酸钠-聚丙烯酰胺凝胶上的表观分子量和净电荷不同。结果与前体蛋白转化为SCBP一致。
