The BLOC1S5 Knockout HCT 116 Polyclonal Cells product comprises a polyclonal population of HCT 116 cells in which the BLOC1S5 gene has been disrupted using CRISPR/Cas9 technology. This polyclonal knockout pool preserves the inherent cellular heterogeneity of a gene-edited population, making it a versatile tool for loss-of-function studies. Researchers can utilize these cells to investigate the role of the BLOC-1 complex in endolysosomal trafficking and lysosome-related organelle biogenesis.
HCT 116 is a human colorectal carcinoma epithelial cell line with a KRAS G13D activating mutation and mismatch repair deficiency due to MLH1 inactivation. This genetic context makes it a widely used model for colorectal cancer research, particularly in studies of oncogenic signaling, DNA repair, and drug response. The addition of BLOC1S5 knockout allows exploration of how endolysosomal trafficking pathways intersect with colorectal cancer biology.
BLOC1S5 encodes a subunit of the biogenesis of lysosome-related organelles complex-1 (BLOC-1). The BLOC-1 complex, composed of subunits including BLOC1S1, BLOC1S2, BLOC1S3, BLOC1S4, BLOC1S6, DTNBP1, PLDN, and SNAPIN, interacts with adaptor complexes AP-1 and AP-3 and clathrin to mediate protein sorting and vesicular trafficking from early endosomes. BLOC1S5 is critical for the delivery of cargoes such as melanogenic enzymes and lysosomal membrane proteins to maturing melanosomes and lysosome-related organelles. Downstream events involve Rab GTPases, the SNARE protein VAMP7, and LAMP1/2, facilitating organelle maturation. Knockout of BLOC1S5 abrogates BLOC-1 function, impairing lysosome-related organelle biogenesis, including melanosome formation and platelet dense granule production, thereby modeling aspects of Hermansky-Pudlak syndrome.
In the HCT 116 colorectal cancer background, BLOC1S5 deficiency may reveal non-canonical roles of endolysosomal trafficking in cancer cell proliferation, autophagy, and response to chemotherapeutics. The KRAS G13D mutation drives constitutive MAPK signaling, while MLH1 deficiency leads to microsatellite instability; both pathways interface with vesicular transport and lysosomal function. Disruption of BLOC1S5 in this line allows dissection of how BLOC-1-dependent trafficking modulates autophagy flux, lysosomal exocytosis, and drug sensitivity, providing a platform to study the intersection of oncogenic stress and organelle homeostasis.
Researchers can employ these cells to examine the impact of BLOC1S5 loss on endolysosomal dynamics using LysoTracker staining and immunofluorescence for LAMP1/2. Autophagy flux assays and Western blotting for LC3B and p62 enable assessment of degradative pathway alterations. Cell migration assays and drug sensitivity screening with agents such as cisplatin and 5-fluorouracil can uncover roles of BLOC-1 in cancer cell behavior and therapeutic resistance. RT-qPCR and co-immunoprecipitation studies validate interactions with BLOC-1 subunits and adaptor complexes. This product is suitable for studies in cancer cell biology, autophagy regulation, and endosomal trafficking. For additional information, please contact Ascent Research.
