Selenof Knockout HT22 Cell Line

The Selenof Knockout HT22 Cell Line is a CRISPR/Cas9-edited knockout cell line derived from the immortalized mouse hippocampal neuronal HT22 line, engineered to disrupt the Selenof gene. This product provides a defined loss-of-function model for investigating the roles of the endoplasmic reticulum (ER)-resident selenoprotein Selenof (Sep15) in protein quality control and ER stress signaling. The knockout cell line is supplied as a ready-to-use cell culture product suitable for a variety of biochemical, cell biological, and pharmacological studies.

The HT22 host line is a subclone of the HT4 mouse hippocampal cell line, selected for its sensitivity to glutamate-induced oxidative stress. HT22 cells are widely used as a model for oxidative glutamate toxicity and neuronal apoptosis, lacking ionotropic glutamate receptors but susceptible to cystine/glutamate antiporter inhibition, leading to glutathione depletion and oxidative cell death. This makes the HT22 background particularly valuable for studying redox-regulated neuronal survival and death pathways.

Selenof functions as an oxidoreductase in the ER, where it partners with UDP-glucose:glycoprotein glucosyltransferase 1 (UGGT1) to catalyze reglucosylation of misfolded glycoproteins, a critical step for their engagement with the calnexin/calreticulin chaperone system. Its activity is regulated by selenium availability and the unfolded protein response (UPR) transcription factors ATF4, Nrf2, and ATF6. Selenof interacts physically with UGGT1, SELENOK, SELENOS, and ERp57, and its downstream targets include UGGT1 glycoprotein substrates and ER stress markers such as BiP, CHOP, and spliced XBP1. In the signaling network, Selenof lies upstream of the PERK/eIF2??/ATF4/CHOP apoptotic axis, and its knockout leads to persistent ER stress and activation of IRE1?? and ATF6 branches.

In the HT22 neuronal context, Selenof knockout impairs glycoprotein folding quality control, resulting in accumulation of misfolded proteins and unresolved ER stress. This triggers the PERK/eIF2??/ATF4 pathway, upregulating CHOP and caspase-12 to promote apoptosis, mimicking aspects of protein misfolding neurodegeneration. The model is thus highly relevant for dissecting how ER proteostasis failure contributes to neuronal vulnerability in diseases like Alzheimer??s, Parkinson??s, and other neurodegenerative disorders, as well as for studying cellular responses to oxidative injury.

This knockout cell line enables detailed investigation of ER stress mechanisms in neurons, selenoprotein biology, and redox homeostasis. It is well-suited for drug screening of UPR modulators using assays such as Western blot for BiP and CHOP, RT-qPCR for XBP1s and ATF4, or cell viability measurements under tunicamycin or thapsigargin challenge. Co-immunoprecipitation can probe Selenof-UGGT1 interactions, while ROS detection and Seahorse metabolic analysis assess oxidative and bioenergetic consequences. Flow cytometry for Annexin V staining quantifies apoptosis induction. For further details or to inquire about this product, contact Ascent Research.