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<MSIGDB BUILD_DATE="Jan 29, 2026" VERSION="2026.1.Hs" NAME="export">
    <GENESET STANDARD_NAME="RIZ_ERYTHROID_DIFFERENTIATION_APOBEC2" SYSTEMATIC_NAME="M15638" HISTORICAL_NAMES="" PMID="17213805" AUTHORS="Riz I,Akimov SS,Eaker SS,Baxter KK,Lee HJ,Mariño-Ramírez L,Landsman D,Hawley TS,Hawley RG" GEOID="" EXACT_SOURCE="Table 5S" GENESET_LISTING_URL="" EXTERNAL_DETAILS_URL="" CHIP="AFFY_MG_U74" CONTRIBUTOR="Leona Saunders" CONTRIBUTOR_ORG="MSigDB Team" DESCRIPTION_BRIEF="Selected genes whose expression profile follows that of APOBEC2 [GeneID=10930] in the TLX1 [GeneID=3195] Tet On iEBHX15-4 cells (pro-erythroblasts)." DESCRIPTION_FULL="Aberrant expression of the human homeobox-containing proto-oncogene TLX1/HOX11 inhibits hematopoietic differentiation programs in a number of murine model systems. Here, we report the establishment of a murine erythroid progenitor cell line, iEBHX1S-4, developmentally arrested by regulatable TLX1 expression. Extinction of TLX1 expression released the iEBHX1S-4 differentiation block, allowing erythropoietin-dependent acquisition of erythroid markers and hemoglobin synthesis. Coordinated activation of erythroid transcriptional networks integrated by the acetyltransferase co-activator CREB-binding protein (CBP) was suggested by bioinformatic analysis of the upstream regulatory regions of several conditionally induced iEBHX1S-4 gene sets. In accord with this notion, CBP-associated acetylation of GATA-1, an essential regulator of erythroid differentiation, increased concomitantly with TLX1 downregulation. Coimmunoprecipitation experiments and glutathione-S-transferase pull-down assays revealed that TLX1 directly binds to CBP, and confocal laser microscopy demonstrated that the two proteins partially colocalize at intranuclear sites in iEBHX1S-4 cells. Notably, the distribution of CBP in conditionally blocked iEBHX1S-4 cells partially overlapped with chromatin marked by a repressive histone methylation pattern, and downregulation of TLX1 coincided with exit of CBP from these heterochromatic regions. Thus, we propose that TLX1-mediated differentiation arrest may be achieved in part through a mechanism that involves redirection of CBP and/or its sequestration in repressive chromatin domains." TAGS="" MEMBERS="100301_at,101059_at,101704_at,102235_at,102580_r_at,102716_at,103050_at,103761_at,104494_at,104506_at,104592_i_at,160615_at,161798_r_at,92334_at,92445_at,92469_at,92726_at,92753_at,92990_at,93075_r_at,94203_at,96507_at,96994_at,97159_at,97745_at,98821_at,99900_at" MEMBERS_SYMBOLIZED="AIRE,CACNA1A,CRX,ESRRB,EVX2,EYA3,HIC1,HNF4G,HOXA4,HOXA6,LCOR,MEF2C,MEIS3,MYCL,NDN,NFATC2,NR1I3,PDX1,PIAS3,SFRP4,SOWAHC,SOX6,TCF21,TFCP2L1,ZNF235" MEMBERS_EZID="10401,1406,2103,2140,29842,3090,3174,3201,3203,326,344191,3651,4208,4610,4692,4773,55553,56917,6424,65124,6943,773,84458,9310,9970" MEMBERS_MAPPING="100301_at,ESRRB,2103|101059_at,NDN,4692|101704_at,HNF4G,3174|102235_at,MYCL,4610|102580_r_at,HOXA6,3203|102716_at,EYA3,2140|103050_at,TCF21,6943|103761_at,TFCP2L1,29842|104494_at,SOWAHC,65124|104506_at,NR1I3,9970|104592_i_at,MEF2C,4208|160615_at,PIAS3,10401|161798_r_at,null,null|92334_at,null,null|92445_at,CACNA1A,773|92469_at,SFRP4,6424|92726_at,SOX6,55553|92753_at,MEIS3,56917|92990_at,ZNF235,9310|93075_r_at,NFATC2,4773|94203_at,LCOR,84458|96507_at,EVX2,344191|96994_at,HIC1,3090|97159_at,AIRE,326|97745_at,HOXA4,3201|98821_at,PDX1,3651|99900_at,CRX,1406" FILTERED_BY_SIMILARITY="" FOUNDER_NAMES="" REFINEMENT_DATASETS="" VALIDATION_DATASETS="" CATEGORY_CODE="C2" ORGANISM="Mus musculus" SUB_CATEGORY_CODE="CGP"/>
</MSIGDB>
