Shark class II invariant chain reveals ancient conserved relationships with cathepsins and MHC class II.

ABSTRACT: The invariant chain (Ii) is the critical third chain required for the MHC class II heterodimer to be properly guided through the cell, loaded with peptide, and expressed on the surface of antigen presenting cells. Here, we report the isolation of the nurse shark Ii gene, and the comparative analysis of Ii splice variants, expression, genomic organization, predicted structure, and function throughout vertebrate evolution. Alternative splicing to yield Ii with and without the putative protease-protective, thyroglobulin-like domain is as ancient as the MHC-based adaptive immune system, as our analyses in shark and lizard further show conservation of this mechanism in all vertebrate classes except bony fish. Remarkable coordinate expression of Ii and class II was found in shark tissues. Conser

SUBMITTER: Criscitiello MF 

PROVIDER: S-EPMC3260380 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature