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The autoimmunity risk variant LYP-W620 cooperates with CSK in the regulation of TCR signaling.

ABSTRACT: The protein tyrosine phosphatase LYP, a key regulator of TCR signaling, presents a single nucleotide polymorphism, C1858T, associated with several autoimmune diseases such as type I diabetes, rheumatoid arthritis, and lupus. This polymorphism changes an R by a W in the P1 Pro rich motif of LYP, which binds to CSK SH3 domain, another negative regulator of TCR signaling. Based on the analysis of the mouse homologue, Pep, it was proposed that LYP and CSK bind constitutively to inhibit LCK and subsequently TCR signaling. The detailed study of LYP/CSK interaction, here presented, showed that LYP/CSK interaction was inducible upon TCR stimulation, and involved LYP P1 and P2 motifs, and CSK SH3 and SH2 domains. Abrogating LYP/CSK interaction did not preclude the regulation of TCR signaling by these proteins.

SUBMITTER: de la Puerta ML

PROVIDER: S-EPMC3554717 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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The autoimmunity risk variant LYP-W620 cooperates with CSK in the regulation of TCR signaling.

de la Puerta María Luisa ML Trinidad Antonio G AG Rodríguez María del Carmen Mdel C de Pereda José María JM Sánchez Crespo Mariano M Bayón Yolanda Y Alonso Andrés A

PloS one 20130124 1

The protein tyrosine phosphatase LYP, a key regulator of TCR signaling, presents a single nucleotide polymorphism, C1858T, associated with several autoimmune diseases such as type I diabetes, rheumatoid arthritis, and lupus. This polymorphism changes an R by a W in the P1 Pro rich motif of LYP, which binds to CSK SH3 domain, another negative regulator of TCR signaling. Based on the analysis of the mouse homologue, Pep, it was proposed that LYP and CSK bind constitutively to inhibit LCK and subse ...[more]

PMID: 23359562

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