MAPK15 Protein, Human (Active, sf9, His-GST)

MAPK15 is an atypical MAPK protein that regulates multiple processes, including autophagy, ciliogenesis, protein trafficking/secretion, and genome integrity, in a kinase activity-dependent manner. It controls both basal and starvation-induced autophagy by interacting with GABARAP, MAP1LC3B, and GABARAPL1, leading to autophagosome formation, SQSTM1 degradation, and reduced inhibitory phosphorylation of MAP1LC3B. Additionally, MAPK15 regulates primary cilium formation and the localization of ciliary proteins involved in structure, transport, and signaling. Under amino acid starvation, it mediates transitional endoplasmic reticulum site disassembly and secretion inhibition. MAPK15 also binds chromatin, activating itself and interacting with PCNA to protect genomic integrity by inhibiting MDM2-mediated PCNA degradation. Furthermore, it modulates DA transporter (DAT) activity and expression via RhoA activation. In response to oxidative stress, MAPK15 phosphorylates ELAVL1, preventing its binding to PDCD4 3'UTR and facilitating PDCD4 mRNA degradation by miR-21. MAPK15 also functions independently of kinase activity as a negative growth regulator (by similar). In vitro, it phosphorylates FOS and MBP. During oocyte maturation, it plays a key role in microtubule organization and meiotic cell cycle progression (by similar). Additionally, MAPK15 interacts with ESRRA, promoting its nuclear-to-cytoplasmic translocation and inhibiting its transcriptional activity.