Insulin receptor-like protein DAF-2 (DAF-2)

Insulin receptor-like protein DAF-2 is a transmembrane receptor tyrosine kinase in Caenorhabditis elegans that serves as the sole ortholog to the human insulin receptor (INSR) and insulin-like growth factor 1 receptor (IGF-1R) [1][2]. It functions as the master regulator of the highly conserved insulin/IGF-1 signaling (IIS) pathway, which coordinates growth, metabolic rate, and longevity in response to nutrient availability [3]. Under favorable conditions, insulin-like peptides bind to DAF-2, activating a phosphorylation cascade involving AGE-1 (PI3K) and AKT-1/2, which sequesters the FOXO transcription factor DAF-16 in the cytoplasm to promote growth and reproduction [4]. Conversely, reduced signaling through DAF-2—either via genetic mutation or pharmacological intervention—triggers the translocation of DAF-16 into the nucleus, activating a suite of genes that enhance stress resistance, proteostasis, and significantly extend the organism's lifespan [2][5]. Because of its profound role in longevity, DAF-2 is a pivotal target in aging research and a primary surrogate for understanding the metabolic and oncogenic roles of its human counterparts [6]. In drug development, while its orthologs are targeted for cancer (IGF-1R) and diabetes (INSR), the therapeutic modulation of this pathway requires careful management of significant metabolic safety concerns, most notably hyperglycemia and growth inhibition [7]. Sources: [1] UniProt (P34708) [2] Kenyon, C., et al. (1993). Nature [3] Murphy, C. T., & Hu, P. J. (2013). WormBook [4] Lin, K., et al. (1997). Science [5] Altintas, O., et al. (2016). Cell Health and Cytoskeleton [6] Fontana, L., et al. (2010). Science [7] Pollak, M. (2012). Nature Reviews Cancer

Other names

Abnormal dauer formation protein 2daf-2Insulin/IGF-1 receptor orthologdaf2

Small molecule inhibition or monoclonal antibody antagonism of the extracellular ligand-binding domain or intracellular tyrosine kinase domain, leading to reduced downstream PI3K/AKT signaling and increased activation of FOXO transcription factors.