KLK9

KLK6

KLK6 (Kallikrein-related peptidase 6) is a serine protease enzyme encoded by the KLK6 gene in humans. It is part of the kallikrein family, which consists of 15 serine proteases with diverse physiological functions. KLK6 is also known by its alternative name, zymogen granule protein 1 (ZGP1).

Structure

KLK6 is synthesized as a preproenzyme, which undergoes post-translational modifications to become an active enzyme. The mature enzyme consists of a single polypeptide chain with a molecular weight of approximately 25 kDa. The active site of KLK6 contains the characteristic serine protease catalytic triad composed of histidine, aspartate, and serine residues.

Function

KLK6 is involved in various physiological processes, including:

• Proteolysis: KLK6 is capable of degrading extracellular matrix components, which is important in tissue remodeling and repair.
• Neurodegeneration: KLK6 is expressed in the central nervous system and has been implicated in neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis.
• Cancer: KLK6 expression is dysregulated in several cancers, including breast, ovarian, and colorectal cancers. It is being studied as a potential biomarker for cancer diagnosis and prognosis.

Expression

KLK6 is predominantly expressed in the central nervous system, particularly in the brain. It is also found in other tissues such as the skin, salivary glands, and the gastrointestinal tract. The expression of KLK6 is regulated by steroid hormones, including androgens and estrogens.

Clinical Significance

KLK6 has been studied for its role in various diseases:

• Alzheimer's Disease: KLK6 is thought to be involved in the degradation of amyloid-beta peptides, which are implicated in the pathogenesis of Alzheimer's disease.
• Multiple Sclerosis: Elevated levels of KLK6 have been found in the cerebrospinal fluid of patients with multiple sclerosis, suggesting a role in the disease's progression.
• Cancer: KLK6 is overexpressed in several types of cancer, and its levels correlate with tumor aggressiveness and patient prognosis.

Research

Ongoing research is focused on understanding the precise biological functions of KLK6 and its potential as a therapeutic target. Studies are exploring the use of KLK6 inhibitors in the treatment of cancer and neurodegenerative diseases.

Also see

• Kallikrein
• Serine protease
• Alzheimer's disease
• Multiple sclerosis
• Cancer biomarker