glycoproteins and proteoglycans

What are glycoproteins?

Glycoproteins are proteins that have carbohydrate groups covalently attached to polypeptide chains. They are involved in cell recognition, signaling, and immune responses.

Where are glycoproteins found?

Glycoproteins are found on the surface of cells, in the extracellular matrix, and in secretions like mucus, hormones, and antibodies.

What types of carbohydrates are attached to glycoproteins?

The carbohydrates attached to glycoproteins are typically oligosaccharides, which may be N-linked (attached to asparagine) or O-linked (attached to serine or threonine).

What is the role of glycoproteins in the immune system?

Glycoproteins, such as antibodies and major histocompatibility complex (MHC) molecules, play a key role in immune recognition and response.

What are proteoglycans?

Proteoglycans contain long, unbranched polysaccharide chains called glycosaminoglycans (GAGs)

What are glycosaminoglycans (GAGs)?

GAGs are long, linear polysaccharides composed of repeating disaccharide units, which are often negatively charged and attract water, contributing to the structural integrity of tissues.

What is the function of proteoglycans?

Proteoglycans provide structural support, maintain hydration in tissues, facilitate cell signaling, and help with tissue repair and development.

How are proteoglycans structured?

Proteoglycans have a core protein with covalently attached GAG chains. The GAGs can be heparan sulfate, chondroitin sulfate, keratan sulfate, or hyaluronic acid.

Where are proteoglycans found?

Proteoglycans are found in the extracellular matrix, cartilage, skin, and other connective tissues.