Granulysin

Granulysin is a protein that in humans is encoded by the GNLY gene. It is a cytolytic and proinflammatory molecule that is found in the granules of human natural killer (NK) cells and cytotoxic T lymphocytes (CTLs).

Structure

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Structure of Granulysin

Granulysin is a small, 9 kDa protein that is highly conserved across species. It is composed of 74 amino acids and has a highly positive charge due to the presence of multiple lysine residues. The protein has a unique structure, with five alpha helices arranged in a compact, saposin-like fold.

Function

Granulysin is involved in the immune response against intracellular pathogens. It is released by cytotoxic cells upon contact with infected or transformed cells. The protein has the ability to form pores in the membranes of target cells, leading to cell lysis and death. In addition to its cytolytic activity, granulysin also has proinflammatory properties. It can induce the production of inflammatory cytokines and chemokines, and can attract other immune cells to the site of infection.

Clinical significance

Alterations in the expression or function of granulysin can have significant clinical implications. Reduced levels of granulysin have been associated with increased susceptibility to certain infections, such as tuberculosis and HIV/AIDS. On the other hand, overexpression of granulysin can contribute to the pathogenesis of autoimmune diseases, such as psoriasis and rheumatoid arthritis.

Research

Research is ongoing to explore the potential use of granulysin in immunotherapy. Due to its potent cytolytic activity, granulysin has been proposed as a potential therapeutic agent for the treatment of cancer and infectious diseases.

See also

• Natural killer cell
• Cytotoxic T cell
• Immunotherapy