This product provides a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colorectal adenocarcinoma cell line, featuring targeted disruption of the BID gene via CRISPR/Cas9-mediated gene disruption. The polyclonal nature preserves a heterogeneous knockout pool, allowing robust loss-of-function investigation of BID within an epithelial cancer model, suitable for studying apoptosis signaling, therapeutic response, and colon cancer biology.
HT29 cells were originally isolated from a 44-year-old female colorectal adenocarcinoma and are widely used as a model for colon cancer. These cells exhibit characteristic epithelial morphology and harbor mutations in APC, TP53, and KRAS, with a microsatellite-stable (MSS) genetic background. This combination of genetic alterations makes HT29 a representative system for examining how oncogenic signaling intersects with apoptotic pathways, providing a relevant context for BID functional studies.
BID encodes a BH3-only pro-apoptotic protein of the Bcl-2 family that serves as a critical link between extrinsic death receptor signaling and the intrinsic mitochondrial apoptosis pathway. Upon activation, BID is cleaved by caspase-8 to generate truncated BID (tBID), which translocates to mitochondria and interacts with BAX and BAK, promoting their oligomerization and mitochondrial outer membrane permeabilization. This event triggers the release of cytochrome c, leading to APAF1-mediated activation of caspase-9 and subsequent executioner caspase-3 activation. BID is regulated by upstream proteases including caspase-8, granzyme B, and cathepsins, and its expression is influenced by p53. It also interacts with anti-apoptotic regulators BCL-2 and Bcl-xL, as well as the mitochondrial receptor MTCH2.
Within the HT29 colorectal cancer background, loss of BID function can significantly alter apoptotic responsiveness, potentially impacting sensitivity to chemotherapeutics and death receptor ligands. The presence of mutant p53 in HT29 cells adds complexity, as p53-dependent transcriptional regulation of BID and other apoptotic components may be compromised. Consequently, this knockout model enables dissection of how colon cancer cells evade apoptosis and may help identify strategies to restore apoptotic signaling or overcome therapeutic resistance by targeting downstream effectors such as BAX, BAK, or cytochrome c release.
This BID knockout HT29 polyclonal cell population is a versatile tool for a wide range of apoptosis-focused studies and drug sensitivity assays in colorectal cancer. Representative applications include western blotting for BID and cytochrome c release, caspase-3/7 activity measurements, Annexin V apoptosis staining by flow cytometry, MTT cell viability assays, JC-1 mitochondrial membrane potential analysis, and co-immunoprecipitation to assess interactions with BCL-2 family members. These approaches support investigations into mitochondrial apoptosis pathway dynamics, cross-talk between intrinsic and extrinsic apoptotic signals, and the role of BID in colon cancer progression. For further information or technical inquiries, please contact Ascent Research.
