Expression of the SH2D1A gene is regulated by a combination of transcriptional and post-transcriptional mechanisms.
The SH2D1A gene, which is altered or deleted in patients with X-linked lymphoproliferative disease, encodes the small protein SAP (for SLAM-associated protein) that is expressed in T and NK cells. A 22-bp fragment in close proximity to an initiator-like site was defined as the basal promoter of mouse SH2D1A, and a highly homologous 33-bp segment was defined as the human basal promoter. When an Ets consensus site was mutated, no reporter activity was detectable. Gel mobility supershift assays revealed that the two transcription factors Ets-1 and Ets-2 bind to the human and mouse sequences. The involvement of Ets-1 and Ets-2 in expression of SH2D1A was functionally confirmed by overexpression studies of their dominant-negative forms. We also found that SH2D1A mRNA decays very rapidly in mouse T cells, and its 3' untranslated region (UTR) has RNA-destabilizing activity in transfection studies with reporter/3' UTR constructs. As judged by RNA-gel mobility shift assays, this rapid degradation of SH2D1A mRNA was due to a balance in binding of the factors AUF1 and HuR to its 3' UTR. Although the SH2D1A mRNA level decreased upon triggering of the T cell receptor (TCR), the RNA degradation rate itself was not altered by TCR engagement.
Okamoto
Susumu
S
Division of Immunology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA.
Ji
Hongbin
H
Howie
Duncan
D
Clarke
Kareem
K
Gullo
Charles
C
Manning
Stephen
S
Coyle
Anthony J
AJ
Terhorst
Cox
C
D020413:3' Untranslated Regions / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000954:Antigens, Surface / Q000378:metabolism; D001483:Base Sequence; D016384:Consensus Sequence; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; D024202:Electrophoretic Mobility Shift Assay; D005786:Gene Expression Regulation / Q000235:genetics*; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D019169:Jurkat Cells; D008232:Lymphoproliferative Disorders / Q000235:genetics* / Q000276:immunology; D051379:Mice; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D050784:Proto-Oncogene Protein c-ets-1; D050787:Proto-Oncogene Protein c-ets-2; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D016601:RNA-Binding Proteins / Q000378:metabolism; D016415:Sequence Alignment; D000071179:Signaling Lymphocytic Activation Molecule Associated Protein; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D020413:3' Untranslated Regions; D000954:Antigens, Surface; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; C098770:ELAVL1 protein, human; C494041:ETS1 protein, human; C494069:ETS2 protein, human; C494042:Ets1 protein, mouse; C494070:Ets2 protein, mouse; C000630986:HNRNPD protein, human; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; C000630987:Hnrpd protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D050784:Proto-Oncogene Protein c-ets-1; D050787:Proto-Oncogene Protein c-ets-2; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C114953:SH2D1A protein, human; C499569:Sh2d1a protein, mouse; D000071179:Signaling Lymphocytic Activation Molecule Associated Protein; D015534:Trans-Activators; D014157:Transcription Factors