Construction and Composition of the Squid Pen from Doryteuthis pealeii.

ABSTRACT: The pen, or gladius, of the squid is an internalized shell. It serves as a site of attachment for important muscle groups and as a protective barrier for the visceral organs. The pen's durability and flexibility are derived from its unique composition of chitin and protein. We report the characterization of the structure, development, and composition of pens from Doryteuthis pealeii. The nanofibrils of the polysaccharide β-chitin are arranged in an aligned configuration in only specific regions of the pen. Chitin is secreted early in development, enabling us to characterize the changes in pen morphology prior to hatching. The chitin and proteins are assembled in the shell sac surrounded by fluid that has a significantly different ionic composition from squid plasma. Two groups of pr

SUBMITTER: Messerli MA 

PROVIDER: S-EPMC7340512 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature