ELAVL1

ELAVL1, also known as HuR (ELAV-like protein 1), is an RNA-binding protein that belongs to the neuronal ELAV (ELAVL) family. It is encoded by the ELAVL1 gene and is broadly expressed in human tissues. Under normal conditions it localizes mainly to the nucleus, but it translocates to the cytoplasm in response to cellular stress or stimuli, where it exerts its regulatory effects on mRNA.

HuR contains three RNA recognition motifs that enable binding to AU-rich elements in the 3' untranslated regions of target mRNAs. Through this binding, HuR generally stabilizes transcripts and can enhance their translation. Its targets include cytokines and inflammatory mediators (such as TNF and IL-6), growth factors (such as VEGF), and cell-cycle regulators (such as c-Myc and Cyclin D1), among others. By stabilizing and regulating these mRNAs, HuR influences processes such as inflammation, cell proliferation, apoptosis, and stress responses. HuR activity is also modulated by interactions with other RNA-binding proteins and microRNAs, and by post-translational modifications that affect its localization and function.

Regulation of HuR involves signaling pathways that promote cytoplasmic accumulation, notably phosphorylation events triggered by stress-activated kinases. HuR can associate with stress granules and messenger ribonucleoprotein complexes, integrating signals related to cellular homeostasis. In disease contexts, HuR upregulation or misregulation has been linked to cancer progression and chronic inflammatory conditions, making it a subject of ongoing research as a potential therapeutic target to modulate mRNA stability and expression.