Themis is a member of a new metazoan gene family and is required for the completion of thymocyte positive selection.

TitleThemis is a member of a new metazoan gene family and is required for the completion of thymocyte positive selection.
Publication TypeJournal Article
Year of Publication2009
AuthorsJohnson AL, Aravind L, Shulzhenko N, Morgun A, Choi S-Y, Crockford TL, Lambe T, Domaschenz H, Kucharska EM, Zheng L, Vinuesa CG, Lenardo MJ, Goodnow CC, Cornall RJ, Schwartz RH
JournalNature immunology
Volume10
Issue8
Pagination831-9
Date Published2009 Aug
ISSN1529-2916
KeywordsAmino Acid Sequence, Animals, CD4-Positive T-Lymphocytes, CD8-Positive T-Lymphocytes, Cell Differentiation, Cell Line, Cell Lineage, Cell Survival, Ethylnitrosourea, Female, Humans, Mice, Molecular Sequence Data, Mutation, Oligonucleotide Array Sequence Analysis, Proteins, Receptors, Antigen, T-Cell, Signal Transduction
Abstract

T cell antigen receptor (TCR) signaling in CD4(+)CD8(+) double-positive thymocytes determines cell survival and lineage commitment, but the genetic and molecular basis of this process is poorly defined. To address this issue, we used ethylnitrosourea mutagenesis to identify a previously unknown T lineage-specific gene, Themis, which is critical for the completion of positive selection. Themis contains a tandem repeat of a unique globular domain (called 'CABIT' here) that includes a cysteine motif that defines a family of five uncharacterized vertebrate proteins with orthologs in most animal species. Themis-deficient thymocytes showed no substantial impairment in early TCR signaling but did show altered expression of genes involved in the cell cycle and survival before and during positive selection. Our data suggest a unique function for Themis in sustaining positive selection.

DOI10.1038/ni.1769
Alternate JournalNat. Immunol.