期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1978
卷号:75
期号:1
页码:390-394
DOI:10.1073/pnas.75.1.390
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Five polypeptide components have been isolated from the eggshell (chorions) of a silkmoth. Two are homogeneous on sodium dodecyl sulfate and isoelectric focusing gels, and three contain predominantly two proteins each. Amino acid analyses show that all five components are similar to each other. These proteins have been sequenced from the amino terminus. Homogeneous components yielded single sequences; heterogeneous components yielded two residues at some positions, consistent with their containing two major electrophoretic components. Striking similarities are apparent among all these sequences. These similarities can be increased dramatically by separating each of the three protein mixtures into two sequences and introducing a small number of gaps or insertions. This is due in part to bringing into register a portion that contains short repeating subunits found in all sequences. All proteins are also characterized by a region of high cysteine content near the amino terminus followed by a longer low-cysteine region. The data suggest that these proteins share a common evolutionary origin and are encoded by a multigene family.