The CCNE1 Knockout HEK293 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout pool of HEK293 cells with targeted disruption of the CCNE1 gene, encoding cyclin E1. This heterogeneous population provides loss-of-function of cyclin E1 across the pool, derived from the commonly used HEK293 human embryonic kidney epithelial line. The polyclonal format avoids clonal biases and is ideal for population-level functional assays.
The host HEK293 cell line is a transformed adherent line originally established by transfection with sheared adenovirus 5 DNA, stably expressing E1A and E1B proteins that drive high-level transgene expression and robust growth. Widely employed for protein production, gene expression studies, and cell-based assays, its ease of transfection makes it a preferred background for generating gene knockouts to study cell cycle and oncogenic signaling.
Cyclin E1 is the regulatory subunit of CDK2, forming a complex that phosphorylates pRb (RB1) to release E2F transcription factors, such as E2F1, activating genes for G1/S transition and DNA replication initiation. CCNE1 is transcriptionally activated by E2F and MYC, and its expression is promoted by MAPK/ERK and PI3K-AKT pathways, while repressed by p53 and TGF-??. Cyclin E1 activity is inhibited by p21 and p27, and its stability is controlled by the SKP2-FBXW7 ubiquitin ligase. Downstream targets include CDC6, DHFR, TK1, and PCNA, and it facilitates MCM loading. Disruption of CCNE1 thus compromises this central cell cycle regulatory hub.
In HEK293 cells, CCNE1 knockout impairs G1/S progression, leading to delayed cell cycle entry and altered proliferation. Cyclin E1 overexpression is a hallmark of multiple cancers, including breast, ovarian, lung, and colorectal, and correlates with poor prognosis in hepatocellular carcinoma, making this model valuable for dissecting its contributions to tumorigenesis and genomic instability. The polyclonal design ensures robust, reproducible phenotypes without clonal artifacts.
This knockout pool supports diverse applications such as mechanistic studies of G1/S regulation, drug target validation for cyclin E1, and high-content screening for proliferation inhibitors. Compatible assays include Western blot, flow cytometry for cell cycle, EdU/BrdU incorporation, co-immunoprecipitation of cyclin E1?CCDK2, RT-qPCR of E2F targets, and luciferase reporter assays. The cells are also suitable for colony formation assays and xenograft tumor models. For further details, contact Ascent Research.
