Collagen Type IX Alpha1 (COL9A1) ELISA Kit for Rat

This gene encodes one of the three alpha chains of type IX collagen, which is a minor (5-20%) collagen component of hyaline cartilage. Type IX collagen is usually found in tissues containing type II collagen, a fibrillar collagen. Studies in knockout mice have shown that synthesis of the alpha 1 chain is essential for assembly of type IX collagen molecules, a heterotrimeric molecule, and that lack of type IX collagen is associated with early onset osteoarthritis. Mutations in this gene are associated with osteoarthritis in humans, with multiple epiphyseal dysplasia, 6, a form of chondrodysplasia, and with Stickler syndrome, a disease characterized by ophthalmic, orofacial, articular, and auditory defects. Two transcript variants that encode different isoforms have been identified for this gene. [provided by RefSeq, Jul 2008]

COL9A1: Structural component of hyaline cartilage and vitreous of the eye. Defects in COL9A1 are the cause of multiple epiphyseal dysplasia type 6 (EDM6). A generalized skeletal dysplasia associated with significant morbidity. Joint pain, joint deformity, waddling gait, and short stature are the main clinical signs and symptoms. Radiological examination of the skeleton shows delayed, irregular mineralization of the epiphyseal ossification centers and of the centers of the carpal and tarsal bones. Multiple epiphyseal dysplasia is broadly categorized into the more severe Fairbank and the milder Ribbing types. The Fairbank type is characterized by shortness of stature, short and stubby fingers, small epiphyses in several joints, including the knee, ankle, hand, and hip. The Ribbing type is confined predominantly to the hip joints and is characterized by hands that are normal and stature that is normal or near-normal. Defects in COL9A1 are the cause of Stickler syndrome type 4 (STL4). An autosomal recessive form of Stickler syndrome, an inherited disorder that associates ocular signs with more or less complete forms of Pierre Robin sequence, bone disorders and sensorineural deafness. Ocular disorders may include juvenile cataract, myopia, strabismus, vitreoretinal or chorioretinal degeneration, retinal detachment, and chronic uveitis. Robin sequence includes an opening in the roof of the mouth (a cleft palate), a large tongue (macroglossia), and a small lower jaw (micrognathia). Bones are affected by slight platyspondylisis and large, often defective epiphyses. Juvenile joint laxity is followed by early signs of arthrosis. The degree of hearing loss varies among affected individuals and may become more severe over time. Syndrome expressivity is variable. Belongs to the fibril-associated collagens with interrupted helices (FACIT) family. 3 isoforms of the human protein are produced by alternative splicing.

Protein type: Secreted; Secreted, signal peptide

Chromosomal Location of Human Ortholog: 6q13

Cellular Component: proteinaceous extracellular matrix; endoplasmic reticulum lumen; extracellular region

Molecular Function: metal ion binding; extracellular matrix structural constituent conferring tensile strength

Biological Process: axon guidance; extracellular matrix disassembly; collagen catabolic process; extracellular matrix organization and biogenesis; organ morphogenesis; tissue homeostasis

Disease: Stickler Syndrome, Type Iv; Epiphyseal Dysplasia, Multiple, 6