Caterpillar Paralytic Proteins

Silkworm

Silkworm, Bombyx mori

Caterpillars of silkworms and other moths are known to produce peptides (cytokines) that can cause larval paralysis. It is speculated that these peptides may serve as a partial defense against parasitoids. The levels of paralytic peptide that can be isolated from the hemolymph of a caterpillar are many times that needed to induce paralysis. How can the caterpillar avoid the paralytic effects of its own peptides?

The peptide circulates in the hemolymph in an inactive form. It can be converted to a modified “paralytic” form by serine proteases that respond to damage to the caterpillar cuticle and loss of hemolymph. The activated protein has a number of biological effects such as paralysis accompanying muscle contraction and changing the shape of hemocytes as part of the immune defensive response of the caterpillar.

Caterpillars are important models for the study of immune response. Knowing how caterpillars fight infections could lead to new methods for fighting human infections.

Soon-Duck Ha, Shinji Nagata, Akinori Suzuki, Hiroshi Karaoke. Isolation and structure determination of a paralytic peptide from the hemolymph of the silkworm, Bombyx mori. Peptides. Volume 20, Issue 5, June 1999, Pages 561-568.
http://dx.doi.org/10.1016/S0196-9781(99)00008-X

About jjneal

Jonathan Neal is an Associate Professor of Entomology at Purdue University and author of the textbook, Living With Insects (2010). This blog is a forum to communicate about the intersection of insects with people and policy. This is a personal blog. The opinions and materials posted here are those of the author and are in no way connected with those of my employer.
This entry was posted in Biomaterials, by jjneal, Caterpillar Blogging. Bookmark the permalink.

One Response to Caterpillar Paralytic Proteins

  1. Pingback: Caterpillar Paralytic Proteins – Entomo Planet

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s