Presenilins

Presenilins are a family of transmembrane proteins that play a crucial role in the development and function of the nervous system. They are primarily found in the endoplasmic reticulum and are essential components of the gamma-secretase complex. This complex is a multi-subunit protease responsible for cleaving various transmembrane proteins, including the amyloid precursor protein (APP).

Mutations in the presenilin genes, PSEN1 and PSEN2, are the most common cause of early-onset familial Alzheimer's disease (FAD). These mutations lead to the production of amyloid-beta peptides, which aggregate and form amyloid plaques in the brain, a hallmark of Alzheimer's pathology. The precise mechanism by which presenilin mutations contribute to neurodegeneration is still under investigation, but it is thought to involve altered gamma-secretase activity and potentially other non-canonical functions of presenilins.

Beyond their role in APP processing, presenilins are involved in a variety of cellular processes, including calcium homeostasis, DNA repair, and regulation of gene expression. Their involvement in these diverse functions suggests a broader role in cellular health and disease beyond their connection to Alzheimer's. Research into presenilins continues to explore their normal physiological functions and their contribution to various neurological disorders. Understanding presenilin biology is vital for developing therapeutic strategies for Alzheimer's disease and potentially other neurodegenerative conditions.