PEAK1 is a scaffolding protein that regulates the cytoskeleton to control cell spreading and migration. It does so by modulating focal adhesion dynamics. UniProt annotates it as a probable catalytically inactive kinase, so its activity is thought to come from organising signalling complexes rather than from phosphotransfer. It acts as a scaffold for mediating EGFR signalling, which links the PEAK1 protein to growth factor receptor pathways.

In migrating cells, PEAK1 is associated with the actin cytoskeleton and with focal adhesions, where it promotes the elongation of developing focal adhesions. Consistent with this, UniProt lists its subcellular locations as the cytoskeleton within the cytoplasm and focal adhesions at cell junctions. The PEAK1 gene is described by NCBI as encoding a non-receptor tyrosine kinase belonging to the new kinase family three (NFK3) family, and the protein is classed within the protein kinase superfamily.

HGNC places PEAK1 in the pseudokinases group and the PEAK pseudokinase family. Its approved name, pseudopodium enriched atypical kinase 1, reflects this atypical kinase character. Other names include KIAA2002 and sgk269, and the mouse ortholog is Peak1. According to the NCBI Gene summary, PEAK1 may play a role in the regulation of cell migration, proliferation and cancer metastasis, which makes it a topic of interest in cell motility and tumour biology.