Fos B Rabbit mAb

Fos B Rabbit mAb detects endogenous levels of total Fos B protein.

FosB is an immediate early gene and member of the Fos family of transcription factors that regulates gene expression in response to various stimuli, including stress, drugs, and neuronal activity. Structurally, FosB contains a basic leucine zipper (bZIP) domain essential for DNA binding and dimerization with Jun proteins to form active AP-1 transcription factor complexes. The FosB gene consists of four exons and generates multiple splice variants, including full-length FosB, the highly stable ΔFosB, and Δ2ΔFosB, each with distinct regulatory properties. FosB is dynamically expressed across tissues, with prominent induction in the brain, particularly in the nucleus accumbens, following repeated stress or drug exposure. Functionally, ΔFosB accumulates due to the absence of degron domains and phosphorylation at Ser27, enabling long-lasting transcriptional effects that promote reward sensitivity, stress resilience, and responses to antidepressants, thus playing a critical role in neuroplasticity and behavioral adaptation.