This gene is a member of the aggrecan/versican proteoglycan family. The encoded protein is an integral part of the extracellular matrix in cartilagenous tissue and it withstands compression in cartilage. Mutations in this gene may be involved in skeletal dysplasia and spinal degeneration. Multiple alternatively spliced transcript variants that encode different protein isoforms have been observed in this gene. [provided by RefSeq]

ACAN iso3: This proteoglycan is a major component of extracellular matrix of cartilagenous tissues. A major function of this protein is to resist compression in cartilage. It binds avidly to hyaluronic acid via an N-terminal globular region. Defects in ACAN are the cause of spondyloepiphyseal dysplasia type Kimberley (SEDK). Spondyloepiphyseal dysplasias are a heterogeneous group of congenital chondrodysplasias that specifically affect epiphyses and vertebrae. The autosomal dominant SEDK is associated with premature degenerative arthropathy. Defects in ACAN are the cause of spondyloepimetaphyseal dysplasia aggrecan type (SEMD-ACAN). A bone disease characterized by severe short stature, macrocephaly, severe midface hypoplasia, short neck, barrel chest and brachydactyly. The radiological findings comprise long bones with generalized irregular epiphyses with widened metaphyses, especially at the knees, platyspondyly, and multiple cervical-vertebral clefts. Defects in ACAN are the cause of osteochondritis dissecans short stature and early-onset osteoarthritis (OD). It is a type of osteochondritis defined as a separation of cartilage and subchondral bone from the surrounding tissue, primarily affecting the knee, ankle and elbow joints. It is clinically characterized by multiple osteochondritic lesions in knees and/or hips and/or elbows, disproportionate short stature and early-onset osteoarthritis. Belongs to the aggrecan/versican proteoglycan family. 3 isoforms of the human protein are produced by alternative splicing.

Protein type: Secreted; Cell adhesion; Extracellular matrix; Secreted, signal peptide

Chromosomal Location of Human Ortholog: 15q26.1

Cellular Component: extracellular matrix; proteinaceous extracellular matrix; lysosomal lumen; Golgi lumen; extracellular region

Molecular Function: protein binding; extracellular matrix structural constituent; metal ion binding; hyaluronic acid binding; carbohydrate binding

Biological Process: keratan sulfate metabolic process; extracellular matrix disassembly; extracellular matrix organization and biogenesis; glycosaminoglycan metabolic process; carbohydrate metabolic process; keratan sulfate biosynthetic process; pathogenesis; keratan sulfate catabolic process; cell adhesion; proteolysis; skeletal development

Disease: Spondyloepiphyseal Dysplasia, Kimberley Type; Spondyloepimetaphyseal Dysplasia, Aggrecan Type