Isolation of Messenger RNA Coding for Eggshell Protein of the DNA‐Eliminating Nematode Ascaris lumbricoides

Abstract

Poly(A)-containing RNA from polyploid uterine epithelial cells of A. lumbricoides was isoalted by poly(U)-Sepharose chromatography. The bulk of poly(A)-containing RNA migrates as 18-S RNA in formamide/polyacrylamide gels. In a cell-free wheat germ system, this RNA directs synthesis of a polypeptide with identical migration behavior in dodecylsulfate/urea/polyacrylamide gels as the polypeptide isolated from the proteinaceous eggshell. The 2 proteins reveal almost identical peptide patterns in fingerprint analysis. The authentic eggshell protein was identified as a glycoprotein with a MW of about 10,000, as determined by dodecylsulfate/polyacrylamide gel electrophoresis. The apparent discrepancy between mRNA length and the required coding length for the protein is discussed.