Suomalainen M, Garoff H, Baron M D
Department of Molecular Biology, Karolinska Institute, Novum, Huddinge, Sweden.
J Virol. 1990 Nov;64(11):5500-9. doi: 10.1128/JVI.64.11.5500-5509.1990.
The capsid (C) protein of rubella virus is translated from a 24S subgenomic mRNA as the first part of a polyprotein containing all three structural proteins of the virus. It is separated from the following protein (E2) by signal peptidase, which cleaves after the E2 signal sequence. We raised an antipeptide antiserum directed against the signal sequence and used the antiserum to show that this sequence is still a part of the C protein in the mature virion. Furthermore, we also showed that, when the C protein is synthesized by in vitro transcription and translation, the resultant protein is membrane associated. This association is not seen with a variant C protein which lacks the signal sequence, and a normally soluble protein (dihydrofolate reductase) becomes membrane associated when the signal sequence is placed at its carboxy terminus.
风疹病毒的衣壳（C）蛋白由24S亚基因组mRNA翻译而来，是包含病毒所有三种结构蛋白的多蛋白的第一部分。它通过信号肽酶与后续蛋白（E2）分离，信号肽酶在E2信号序列之后进行切割。我们制备了一种针对该信号序列的抗肽抗血清，并使用该抗血清证明该序列在成熟病毒粒子中仍是C蛋白的一部分。此外，我们还表明，当通过体外转录和翻译合成C蛋白时，产生的蛋白与膜相关。缺乏信号序列的变异C蛋白则不会出现这种关联，而当信号序列置于正常可溶性蛋白（二氢叶酸还原酶）的羧基末端时，该蛋白会与膜相关。
