Keratin 1 is a type of protein that is a key component of the outer layer of human skin, as well as hair and nails. It belongs to a family of proteins known as keratins, which provide structural support and protection. Keratin 1 is particularly important for maintaining the integrity and barrier function of the skin. This protein is produced by specialized skin cells called keratinocytes. When these cells mature, they produce keratin 1, which helps form a tough, protective layer on the skin's surface. This process is essential for preventing water loss and protecting against environmental damage.