Boccaccio G L, Quesada-Allué L A
Instituto de Investigaciones Bioquímicas, Fundación Campomar, Universidad de Buenos Aires, Argentina.
Biochem Biophys Res Commun. 1989 Oct 16;164(1):251-8. doi: 10.1016/0006-291x(89)91710-5.
Cuticle proteins of an insect pest, the Medfly Ceratitis capitata, were resolved in polyacrylamide gels and partially characterized. The pupal cuticle was found to be different from cuticles of other insects since more than 80% w/w of the protein is a single mannose-containing polypeptide (PCG-100). The temporally-regulated in vivo biosynthesis and deposition of cuticle proteins was studied by microinjection of [35S]methionine followed by hand dissection of pupal cuticles. The major pupal glycoprotein, PCG-100, is cuticle- and stage-specific and was the earliest to be labeled and deposited. Its synthesis was maximal at around 46 hours after pupariation and then it decreased. The deposited PCG-100 and other minor pupal cuticle proteins become non-extractable at the end of the instar (7 days after pupariation) probably by sclerotization phenomena. These results provide insight into the temporal control of gene expression programs involved in cuticle deposition during medfly metamorphosis.
对害虫地中海实蝇（Ceratitis capitata）的表皮蛋白进行了聚丙烯酰胺凝胶电泳分析，并对其进行了部分表征。发现蛹表皮与其他昆虫的表皮不同，因为超过80%（重量/重量）的蛋白质是一种单一的含甘露糖多肽（PCG-100）。通过显微注射[35S]甲硫氨酸，然后手工解剖蛹表皮，研究了表皮蛋白在体内的时间调控生物合成和沉积。主要的蛹期糖蛋白PCG-100具有表皮特异性和阶段特异性，是最早被标记和沉积的。其合成在化蛹后约46小时达到最大值，然后下降。沉积的PCG-100和其他次要的蛹表皮蛋白在龄期末（化蛹后7天）可能由于硬化现象而变得不可提取。这些结果为深入了解地中海实蝇变态过程中表皮沉积所涉及的基因表达程序的时间控制提供了依据。
