What is the structure of Aggrecan?
Aggrecan is a multimodular molecule expressed by chondrocytes. Its core protein is composed of three globular domains (G1, G2, and G3) and a large extended region (CS) between G2 and G3 for glycosaminoglycan chain attachment. G1 comprises the amino terminus of the core protein.
What are proteoglycans structure?
Proteoglycans consist of a core protein and one or more covalently attached GAG chains (Figure 11.2). GAGs are linear polysaccharides, whose building blocks (disaccharides) consist of an amino sugar (either GlcNAc or GalNAc) and an uronic acid (GlcA and IdoA).
What do you mean by proteoglycans?
Definition of proteoglycan : any of a class of glycoproteins of high molecular weight that are found especially in the extracellular matrix of connective tissue.
Is aggrecan extracellular matrix?
It is present in the extracellular matrix in the form of proteoglycan aggregates, in which many aggrecan molecules interact with hyaluronan and a link protein stabilizes each interaction.
What is aggrecan degradation?
Aggrecan degradation is the hallmark of cartilage degeneration in osteoarthritis (OA), though it is unclear whether a common proteolytic process occurs in all individuals.
What are proteoglycans examples?
Examples of proteoglycans are versican (a large chondroitin sulfate proteoglycan), perlecan, neurocan, aggrecan, brevican, fibromodulin, and lumican.
Is Heparin a proteoglycan?
Heparin is synthesized by mast cells as a proteoglycan with very high molecular weight GAG chains that are then depolymerized by endoglycosidases to obtain the final product.
What are examples of proteoglycan?
Is Aggrecan found in bone?
Aggrecan is the major structural macromolecule of cartilage, which contributes to water retention and provides resistance to compression. Whereas cartilage is localized on the joint surface and help movement of individuals, it serves as a primodium of most bones during development.
What is Aggrecan degradation?
How does Aggrecan affect cartilage function?
Aggrecanases are not able to cleave link protein (Roughley et al. 2003). While cleavage of link protein may be of no functional consequence, cleavage of aggrecan and HA are detrimental to cartilage function as they reduce both the size and charge of the aggregates.
What is aggrecan and what is its function?
Aggrecan is the major proteoglycan in the articular cartilage. This molecule is important in the proper functioning of articular cartilage because it provides a hydrated gel structure (via its interaction with hyaluronan and link protein) that endows the cartilage with load-bearing properties. It is … Structure and function of aggrecan
What are the globular domains of aggrecan?
Aggrecan is a multimodular molecule expressed by chondrocytes. Its core protein is composed of three globular domains (G1, G2, and G3) and a large extended region (CS) between G2 and G3 for glycosaminoglycan chain attachment. G1 comprises the amino terminus of the core protein. This domain has the same structural motif as link protein.
What is the molecular weight of human aggrecan?
Intact human aggrecan has a molecular weight of approximately 2.5 million Da, with a core protein ranging in apparent molecular weight between 180 and 370kDa with slightly more than 100 GAG chains (mostly CS, but with some KS) of approximately 25kDa.
What is aggrecan in cartilage?
Aggrecan is a large keratan sulfate/chondroitin sulfate-linked proteoglycan (∼2500 kDa), which is prominent in cartilage, but also present in the brain, aorta, and tendons. Its N-terminal domain binds to hyaluronan, an interaction stabilized by link protein.