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     See license terms at www.gsea-msigdb.org/gsea/license_terms_list. Please note that certain gene sets have special access terms.
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<MSIGDB BUILD_DATE="Jan 29, 2026" VERSION="2026.1.Hs" NAME="export">
    <GENESET STANDARD_NAME="BIOCARTA_PS1_PATHWAY" SYSTEMATIC_NAME="M16173" HISTORICAL_NAMES="" PMID="" AUTHORS="" GEOID="" EXACT_SOURCE="" GENESET_LISTING_URL="" EXTERNAL_DETAILS_URL="https://data.broadinstitute.org/gsea-msigdb/msigdb/biocarta/human/h_ps1Pathway.gif" CHIP="HUMAN_SEQ_ACCESSION" CONTRIBUTOR="BioCarta" CONTRIBUTOR_ORG="BioCarta" DESCRIPTION_BRIEF="Presenilin action in Notch and Wnt signaling" DESCRIPTION_FULL="Presenilin-1 (PS1) is associated with gamma secretase activity that cleaves amyloid precursor protein (APP) and is implicated in Alzheimer's disease. Presenilin-1 is also a component in gamma-secretase activity involved in signaling by the transmembrane protein Notch. Active gamma secretase requires PS-1 N-terminal fragment and a C-terminal fragment and is unique in catalyzing proteolysis within the transmembrane region of proteins. Other proteins such as nicastrin may also be components of the gamma-secretase. Binding of the ligand Delta by Notch appears to trigger two proteolytic cleavages of Notch. The first step cleaves an extracellular domain and is catalyzed by a metalloprotease termed alpha-secretase or TACE. The second cleavage step appears to occur within the transmembrane domain of Notch, and releases a Notch intracellular doman (NICD). Once released, NICD moves into the nucleus where it is involved in transcriptional regulation through CSL family transcription factors (CBF1, Su(H), Lag-1) or other transcriptional regulators such as LEF-1. Presenilin is also involved in the Wnt/frizzled signaling pathway through beta-catenin. Beta-catenin is a cytoskeletal component that enters the nucleus to act as a transcriptional cofactor. Binding of WNT to Frizzled causes disheveled (DSH) to inhibit Glycogen synthase kinase 3 beta (GSK-3b) activity. Phosphorylation of Beta-catenin induces the ubiquitination and proteolytic degradation of beta-catenin by the proteasome. Non-phosphorylated beta-catenin is stable and enters the nucleus to regulate transcription with TCF. The beta-catenin/TCF complex activates genes that promote cellular survival, proliferation and differentiation during development. Presenilin stimulates beta-catenin turnover, reducing its transcriptional activation." TAGS="" MEMBERS="BM544433,NM_000021,NM_000038,NM_000545,NM_001098209,NM_001098210,NM_001127510,NM_001127511,NM_001146156,NM_001256856,NM_001904,NM_002093,NM_003183,NM_003502,NM_003505,NM_003939,NM_004421,NM_005349,NM_005430,NM_005618,NM_007318,NM_015874,NM_017617,NM_033637,NM_181050,NM_203283,NM_203284" MEMBERS_SYMBOLIZED="ADAM17,APC,AXIN1,BTRC,CTNNB1,DLL1,DVL1,FZD1,GSK3B,HNF1A,NOTCH1,PSEN1,RBPJ,WNT1" MEMBERS_EZID="1499,1855,28514,2932,324,3516,4851,5663,6868,6927,7471,8312,8321,8945" MEMBERS_MAPPING="BM544433,BTRC,8945|NM_000021,PSEN1,5663|NM_000038,APC,324|NM_000545,HNF1A,6927|NM_001098209,CTNNB1,1499|NM_001098210,CTNNB1,1499|NM_001127510,APC,324|NM_001127511,APC,324|NM_001146156,GSK3B,2932|NM_001256856,BTRC,8945|NM_001904,CTNNB1,1499|NM_002093,GSK3B,2932|NM_003183,ADAM17,6868|NM_003502,AXIN1,8312|NM_003505,FZD1,8321|NM_003939,BTRC,8945|NM_004421,DVL1,1855|NM_005349,RBPJ,3516|NM_005430,WNT1,7471|NM_005618,DLL1,28514|NM_007318,PSEN1,5663|NM_015874,RBPJ,3516|NM_017617,NOTCH1,4851|NM_033637,BTRC,8945|NM_181050,AXIN1,8312|NM_203283,RBPJ,3516|NM_203284,RBPJ,3516" FILTERED_BY_SIMILARITY="" FOUNDER_NAMES="" REFINEMENT_DATASETS="" VALIDATION_DATASETS="" CATEGORY_CODE="C2" ORGANISM="Homo sapiens" SUB_CATEGORY_CODE="CP:BIOCARTA"/>
</MSIGDB>
