Phosphatidylethanolamine-binding protein 1 (PEBP1)

Phosphatidylethanolamine-binding protein 1 (PEBP1), also known as Raf kinase inhibitory protein (RKIP), is a small, evolutionarily conserved cytoplasmic protein (~21-25 kDa) belonging to the PEBP family[1][2]. PEBP1 regulates numerous cellular signaling cascades, including Raf/MEK/ERK (MAPK), NFκB, PI3K/Akt/mTOR, p38, Notch, and Wnt pathways, primarily through inhibitory modulation of kinase–kinase interactions[1][2]. It acts as a metastasis suppressor, notably in prostate and other cancers, and is involved in neurodevelopment, cardiac function, and spermatogenesis[1][3][4]. Dysregulated expression or mutation of PEBP1 is linked to various disease states, including cancer progression, neurodegeneration (such as Alzheimer’s disease), diabetes, kidney disorders, and cardiovascular disease[1][2][3][4]. Despite being an attractive research target, there are currently no approved drugs that directly target PEBP1 in the clinic. Its physiological role is primarily as a regulator of signal transduction and maintenance of cellular homeostasis by modulating the output and responsiveness of critical signaling pathways in response to extracellular stimuli and feedback signals[1][2][3][4].

Other names

Raf kinase inhibitory protein (RKIP)Hippocampal cholinergic neurostimulating peptide (HCNP)Neuropolypeptide h3Prostatic-binding protein (PBP)Epididymis luminal protein 210HEL-210HCNPppEpididymis secretory protein Li 34Epididymis secretory protein Li 96

Allosteric inhibition of kinase–kinase interactions (e.g., blocks Raf-1 binding to and activation of MEK). Negative regulator of kinases within signal transduction pathways. Switches its binding/inhibitory activities between Raf-1 and GRK2 upon phosphorylation by PKC and PKA, affecting β-adrenergic signaling in the heart[2][4]. Modulates apoptosis sensitivity through impact on NFκB and death receptor signaling[2]