This product consists of a CRISPR/Cas9-edited polyclonal knockout cell population derived from the MES-OV human ovarian endometrioid adenocarcinoma cell line, engineered to disrupt the CBS gene encoding cystathionine ??-synthase. The polyclonal format provides a heterogeneous pool of cells carrying diverse editing events, enabling robust functional studies without clonal selection artifacts. This loss-of-function model serves as a powerful tool for dissecting the transsulfuration pathway and associated metabolic and signaling networks in an ovarian cancer context.
The MES-OV parental cell line is an adherent epithelial model established from a primary ovarian endometrioid adenocarcinoma. It is extensively employed in ovarian cancer research for investigating mechanisms of tumorigenesis, drug resistance, and metabolic reprogramming. As a representative of the endometrioid subtype, MES-OV retains key characteristics of the disease, making it a relevant host for evaluating the contribution of specific genes to cancer cell physiology.
CBS is a key enzyme in the transsulfuration pathway, catalyzing the condensation of homocysteine and serine to generate cystathionine. This reaction commits homocysteine to the synthesis of cysteine, the rate-limiting precursor for the antioxidant glutathione and the gasotransmitter hydrogen sulfide (H2S). CBS activity is allosterically activated by S-adenosylmethionine (SAM) and requires heme as a cofactor; it is regulated at the transcriptional level by transcription factors such as SP1 and NF-??B. CBS interacts with cystathionine ??-lyase (CSE), the Elongin BC complex, and calmodulin, and its product cystathionine is cleaved by CSE to cysteine, directly fueling glutathione biosynthesis via glutamate-cysteine ligase (GCL) and glutathione synthetase (GSS) and supporting H2S production by multiple enzymes including 3-mercaptopyruvate sulfurtransferase (3-MST).
In MES-OV cells, disruption of CBS leads to a blockade of the transsulfuration pathway, resulting in accumulation of homocysteine and depletion of cystathionine and downstream metabolites. The consequent reduction in cysteine availability limits glutathione synthesis and H2S production, thereby compromising cellular redox homeostasis and potentially altering proliferative and survival signaling. This model captures the metabolic vulnerability of ovarian cancer cells to perturbations in sulfur amino acid metabolism and provides a physiologically relevant system for studying the interplay between homocysteine handling, oxidative stress responses, and H2S-mediated signaling in a tumorigenic background.
This CBS knockout polyclonal population is suited for a broad range of experimental applications, including quantitative analysis of homocysteine and cystathionine via HPLC or LC-MS, assessment of glutathione and H2S using colorimetric or fluorescent probes, and evaluation of redox-sensitive phenotypes such as ROS accumulation and cell viability under oxidative challenge. It can be employed in functional assays to investigate metabolic dependencies, screen for modulators of the transsulfuration pathway, and explore the epigenetic consequences of altered methylation patterns. Additional downstream analyses include Western blotting (CBS, CSE), RT-qPCR, colony formation, migration/invasion assays, and global metabolomics. For further details, contact Ascent Research.
