FYN

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

FYN is a protein produced by the FYN gene in humans. It is a 59‑kDa enzyme in the Src family of non-receptor tyrosine kinases. Fyn sits on the inner surface of the cell membrane and helps pass signals from outside the cell to the inside, guiding cell growth, movement, and survival.

Fyn plays important roles in T-cell and neuronal signaling, development, and fertilization. It works with other signaling proteins such as PI3K, FAK, and paxillin to regulate how cells attach to surfaces and how they move.

There are multiple forms of Fyn due to alternative splicing. It is activated by many receptors and triggers downstream pathways that affect gene expression and cell behavior, including MAPK and PI3K signaling.

Because Fyn helps control cell growth and movement, changes in its activity are linked to cancer. Overexpression or misregulation of Fyn has been observed in several cancers and can promote tumor growth, invasion, and resistance to cell death. Fyn also interacts with EGFR signaling in brain cancer.

Researchers study Fyn inhibitors and strategies to block its interactions with partners like FAK and PXN as potential cancer therapies. Fyn is also being explored for possible roles in Alzheimer’s disease.