Studies with motheaten mice , which lack the SHP1 protein tyrosine phosphatase , indicate that this enzyme plays an important negative role in T cell antigen receptor ( TCR ) signaling .
studies with motheaten mice , which lack the shp1 protein tyrosine phosphatase , indicate that this enzyme plays an important negative role in t cell antigen receptor ( tcr ) signaling .
O O B-other_artificial_source I-other_artificial_source O O O O B-protein_molecule O B-amino_acid_monomer O O O O O O O O O O O O B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group O B-protein_family_or_group O O O