Extracellular Signal-Regulated Kinases (ERKs) are a group of proteins that play a crucial role in transmitting signals from the cell surface to the nucleus. They are part of the mitogen-activated protein kinase (MAPK) pathway, which is activated by various growth factors and hormones. ERKs help regulate important cellular processes such as growth, differentiation, and survival. Once activated, ERKs move into the nucleus, where they can influence gene expression by phosphorylating specific transcription factors. This action helps cells respond to external stimuli, making ERKs essential for processes like cell proliferation and development. Dysregulation of ERK signaling is often associated with diseases, including cancer.