Bcl2l1 Conditional Knockout mouse models

Encoding BCL-xL, Bcl2l1 is the ortholog of human BCL2L1 and provides the dominant antiapoptotic buffer in erythroid precursors, platelets, and neurons, sequestering BAK and BAX BH3 helices in its groove and additionally retrotranslocating BAX from mitochondria back to cytosol to raise the permeabilization threshold. Regulation runs through STAT5 and NF-kappaB dependent transcription, alternative splicing that yields the proapoptotic BCL-xS isoform, and deamidation or Ser62 phosphorylation that weakens ligand binding. Germline deletion is embryonic lethal near E13 with massive apoptosis of immature hematopoietic cells and postmitotic neurons, so conditional flox alleles with lineage-restricted Cre drivers are mandatory rather than optional. Platelet-specific deletion phenocopies the dose-limiting thrombocytopenia of navitoclax and remains the standard platform for interrogating that toxicity. Match allele to question: conditional null for dependency mapping, and humanized knockin when BH3 mimetic selectivity or acquired resistance mutations constitute the readout.

Bcl2l1 conditional knockout mice carry a floxed allele so you delete function only where Cre is active. The germline allele stays intact until you cross to a tissue specific Cre. Labs reach for this design when a global knockout is lethal, when they need adult onset loss, or when regional redundancy hides a whole body phenotype.