CTTn
CTTn, also known as C-terminal telopeptide of type I collagen N-terminal propeptide, is a non-collagenous protein that is a component of type I collagen. It is primarily found in the extracellular matrix of connective tissues, where it plays a crucial role in the organization and stability of collagen fibers. CTTn is synthesized by fibroblasts and other connective tissue cells, and it is secreted into the extracellular space where it binds to the C-terminal telopeptide of type I collagen molecules. This binding helps to stabilize the collagen fibers and contributes to the mechanical properties of connective tissues. CTTn is also involved in the regulation of collagen synthesis and degradation, and it has been implicated in various pathological conditions, including fibrosis, atherosclerosis, and cancer. The levels of CTTn in biological fluids, such as serum and urine, can be used as biomarkers for the diagnosis and monitoring of these conditions. CTTn is a highly conserved protein, and its structure and function have been well-characterized in various species, including humans, rodents, and chickens.