An Immune Effector System in the Protochordate Gut Sheds Light on Fundamental Aspects of Vertebrate Immunity
A variety of germline and somatic immune mechanisms have evolved in vertebrate and invertebrate species to detect a wide array of pathogenic invaders. The gut is a particularly significant site in terms of distinguishing pathogens from potentially beneficial microbes. Ciona intestinalis, a filter-feeding marine protochordate that is ancestral to the vertebrate form, possesses variable region-containing chitin-binding proteins (VCBPs), a family of innate immune receptors, which recognize bacteria through an immunoglobulin-type variable region. The manner in which VCBPs mediate immune recognition appears to be related to the development and bacterial colonization of the gut, and it is likely that these molecules are critical elements in achieving overall immune and physiological homeostasis.
KeywordsAdaptive Immune System Versus Domain Beneficial Microbe Stomach Lumen Frequent Indels
The authors would like to thank both the ASSEMBLE (Association of European Marine Biological Laboratories) program for collaborative support and Barbara Pryor for editorial assistance. LJD is supported by grants from the All Children’s Hospital Foundation and the University of South Florida College of Medicine Sponsored Research; GWL is supported by NIH R01 Al 23338.
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