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Gut immunity in a protochordate involves a secreted immunoglobulin-type mediator binding host chitin and bacteria.

ABSTRACT: Protochordate variable region-containing chitin-binding proteins (VCBPs) consist of immunoglobulin-type V domains and a chitin-binding domain (CBD). VCBP V domains facilitate phagocytosis of bacteria by granulocytic amoebocytes; the function of the CBD is not understood. Here we show that the gut mucosa of Ciona intestinalis contains an extensive matrix of chitin fibrils to which VCBPs bind early in gut development, before feeding. Later in development, VCBPs and bacteria colocalize to chitin-rich mucus along the intestinal wall. VCBP-C influences biofilm formation in vitro and, collectively, the findings of this study suggest that VCBP-C may influence the overall settlement and colonization of bacteria in the Ciona gut. Basic relationships between soluble immunoglobulin-type molecules, endogenous chitin and bacteria arose early in chordate evolution and are integral to the overall function of the gut barrier.

SUBMITTER: Dishaw LJ

PROVIDER: S-EPMC4757023 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Gut immunity in a protochordate involves a secreted immunoglobulin-type mediator binding host chitin and bacteria.

Dishaw Larry J LJ Leigh Brittany B Cannon John P JP Liberti Assunta A Mueller M Gail MG Skapura Diana P DP Karrer Charlotte R CR Pinto Maria R MR De Santis Rosaria R Litman Gary W GW

Nature communications 20160215

Protochordate variable region-containing chitin-binding proteins (VCBPs) consist of immunoglobulin-type V domains and a chitin-binding domain (CBD). VCBP V domains facilitate phagocytosis of bacteria by granulocytic amoebocytes; the function of the CBD is not understood. Here we show that the gut mucosa of Ciona intestinalis contains an extensive matrix of chitin fibrils to which VCBPs bind early in gut development, before feeding. Later in development, VCBPs and bacteria colocalize to chitin-ri ...[more]

PMID: 26875669

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Gut immunity in a protochordate involves a secreted immunoglobulin-type mediator binding host chitin and bacteria.

Publications

Gut immunity in a protochordate involves a secreted immunoglobulin-type mediator binding host chitin and bacteria.

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