Alpha-1-adrenergic receptors (ADRA1B) is a receptor that is considered a protooncogene, as it has been found to induce neoplastic transformation when transfected into NIH 3T3 fibroblasts and other cell lines. ADRA1B normally functions to regulate cellular growth and proliferation and activate various mitogenic responses. In the brain, it may participate in the flight-or-flight response via epinephrine. In immunohistochemistry, ADRA1B has membranous and cytoplasmic positivity in the brain, with highest expression in the cerebral cortex. It is also highly expressed in the liver and spleen, with low to variable levels of positivity in most other tissues throughout the body. References: The UniProt Consortium. Nucleic Acids Res. 47: D506-515 (2019); Nucleic Acids Res. 2016 Jan 4;44(D1):D733-45, PMID:26553804