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More MS news articles for January 2004

Regulation of ZAP-70 Activation and TCR Signaling by Two Related Proteins, Sts-1 and Sts-2

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14738763&dopt=Abstract

Immunity. 2004 Jan;20(1):37-46
Carpino N, Turner S, Mekala D, Takahashi Y, Zang H, Geiger TL, Doherty P, Ihle JN.
Department of Biochemistry, Saint Jude Children's Research Hospital, 38105, Memphis, TN, USA

T cells play a central role in the recognition and elimination of foreign pathogens.

Signals through the T cell receptor (TCR) control the extent and duration of the T cell response.

To ensure that T cells are not inappropriately activated, signaling pathways downstream of the TCR are subject to multiple levels of positive and negative regulation.

Herein, we describe two related proteins, Sts-1 and Sts-2, that negatively regulate TCR signaling.

T cells from mice lacking Sts-1 and Sts-2 are hyperresponsive to TCR stimulation.

The phenotype is accompanied by increased Zap-70 phosphorylation and activation, including its ubiquitinylated forms.

Additionally, hyperactivation of signaling proteins downstream of the TCR, a marked increase in cytokine production by Sts1/2(-/-) T cells, and increased susceptibility to autoimmunity in a mouse model of multiple sclerosis is observed.

Therefore, Sts-1 and Sts-2 are critical regulators of the signaling pathways that regulate T cell activation.