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Title: Evolution of two distinct variable lymphocyte receptors in lampreys: VLRD and VLRE
Jawless vertebrates possess an alternative adaptive immune system in which antigens are recognized by variable lymphocyte receptors (VLRs) generated by combinatorial assembly of leucine-rich repeat (LRR) cassettes. Three types of receptors, VLRA, VLRB, and VLRC, have been previously identified. VLRA- and VLRC-expressing cells are T cell-like, whereas VLRB-expressing cells are B cell-like. Here, we report two types of VLRs in lampreys, VLRD and VLRE, phylogenetically related to VLRA and VLRC. The germline VLRD and VLRE genes are flanked by 39 LRR cassettes used in the assembly of mature VLRD and VLRE, with cassettes from chromosomes containing the VLRA and VLRC genes also contributing to VLRD and VLRE assemblies. VLRD and VLRE transcription is highest in the triple-negative (VLRA−/VLRB−/VLRC−) population of lymphocytes, albeit also detectable in VLRA+ and VLRC+ populations. Tissue distribution studies suggest that lamprey VLRD+ and VLRE+ lymphocytes comprise T-like sublineages of cells.  more » « less
Award ID(s):
1755418
PAR ID:
10529020
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Cell Press
Date Published:
Journal Name:
Cell Reports
Volume:
42
Issue:
8
ISSN:
2211-1247
Page Range / eLocation ID:
112933
Subject(s) / Keyword(s):
1 Two distinct VLRs, VLRD and VLRE, are found in lampreys 2 VLRD and VLRE, phylogenetically close to VLRA and VLRC, expressed in T-like cells 3 Donor cassettes shared inter-chromosomally among mature VLRA, VLRC, VLRD, and VLRE 4 VLRD+ and VLRE+ cells may be part of the T cell arm of lamprey immunity
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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