The Nrep Knockout 4T1 Cell Line is a CRISPR/Cas9-edited mouse mammary carcinoma cell line in which the Nrep gene has been disrupted to ablate its function. Nrep (also designated P311) is a key regulator of cell migration, proliferation, and differentiation, primarily through enhancement of TGF-?? signaling and promotion of epithelial-mesenchymal transition (EMT). By eliminating Nrep expression, this knockout model enables detailed investigation of its role in these processes.
The parental 4T1 cell line is a well-characterized, highly metastatic mammary carcinoma isolated from a spontaneous BALB/c mouse tumor. It forms aggressive, poorly differentiated tumors that spontaneously metastasize to distant organs, closely mimicking stage IV human breast cancer. Its epithelial origin and robust invasive capacity make it a preferred syngeneic model for studying the molecular mechanisms of metastasis and for evaluating anti-metastatic therapies.
At the molecular level, Nrep functions as a positive modulator of TGF-?? signaling. It is transcriptionally activated by TGF-?? and hypoxia, and in turn interacts with TGFBR1, ITGA5, and ACTA2 to potentiate the pathway. Nrep enhances SMAD2/3 phosphorylation and promotes the expression of matrix metalloproteinases MMP-2 and MMP-9, integrin alpha5, and the mesenchymal transcription factors SNAI1 and TWIST1. These downstream effectors collectively orchestrate extracellular matrix degradation, cytoskeletal remodeling, and the EMT gene program, thereby facilitating cell motility and invasion.
In the 4T1 cellular context, Nrep knockout significantly attenuates TGF-??-driven EMT and cell migration, leading to reduced invasive and metastatic potential. This engineered cell line provides a stringent, physiologically relevant model for dissecting Nrep-dependent signaling network and for comparing the metastatic behavior of Nrep-proficient versus -deficient carcinoma cells. It is particularly valuable for studying the contribution of Nrep to the highly aggressive phenotype of 4T1 cells.
This knockout cell line is suited for a wide range of functional and mechanistic studies. In vitro applications include Transwell migration/invasion assays, wound healing assays, and TGF-?? signaling reporter assays to assess pathway activity. Changes in EMT marker expression can be monitored via Western blotting and immunofluorescence, while RT-qPCR can quantify transcriptional alterations in MMPs, integrins, and transcription factors. For in vivo metastasis studies, the line can be implanted orthotopically or intravenously in syngeneic BALB/c mice to evaluate spontaneous metastasis. For technical support, please contact Ascent Research.
