Osteopontin
Osteopontin, encoded by the SPP1 gene and also known as OPN, BSPI and ETA-1, is a secreted protein that anchors osteoclasts to mineralised bone matrix. It also acts as a cytokine that shapes type I immune responses. Browse Assay Genie's current range of Osteopontin research reagents below, or read on for the biology behind the target.
Osteopontin has two well-described roles. In bone, it is involved in the attachment of osteoclasts to the mineralised bone matrix, and the secreted protein binds hydroxyapatite with high affinity. The osteoclast vitronectin receptor, which sits in the cell membrane, may be involved in binding to it. In the immune system, osteopontin acts as a cytokine. It enhances production of interferon-gamma and interleukin-12 and reduces production of interleukin-10. It is described as essential in the pathway that leads to type I immunity.
The SPP1 gene (secreted phosphoprotein 1) encodes osteopontin, which belongs to the osteopontin family. HGNC classifies it within the SIBLING family and the receptor ligands gene group. Several transcript variants encoding different isoforms have been reported for this gene, so it is worth defining which form of the osteopontin protein is under study when designing experiments or interpreting results.
The nomenclature reflects its history. The protein was previously listed as osteopontin and as bone sialoprotein I, which explains the alias BSPI. Other names in use include OPN, ETA-1, BNSP and lnc-PKD2-2-3. Because the literature uses these names interchangeably, searching under several of them gives a fuller picture of osteopontin biology. Its dual identity as a bone matrix component and an immune-modulating cytokine makes it a useful point of connection between skeletal and immunological research.
Osteopontin is involved in osteoclast attachment to mineralised bone matrix and binds hydroxyapatite with high affinity.
Osteopontin is essential in the pathway leading to type I immunity, making it relevant to studies of cell-mediated immune responses.
Osteopontin enhances interferon-gamma and interleukin-12 production while reducing interleukin-10, a pattern studied in cytokine balance.
The osteoclast vitronectin receptor may be involved in osteopontin binding, which supports work on ligand and receptor engagement.
Osteopontin is secreted and binds hydroxyapatite with high affinity. It is involved in attaching osteoclasts to the mineralised bone matrix. It also acts as a cytokine, raising interferon-gamma and interleukin-12 production, lowering interleukin-10 production and supporting type I immunity.
Osteopontin is encoded by SPP1 and is also called OPN, BSPI, ETA-1, BNSP and lnc-PKD2-2-3. Earlier names were osteopontin and bone sialoprotein I. Several transcript variants encoding different isoforms have been identified for the gene.
A rat ortholog, Spp1, is recorded for the human gene. Osteopontin belongs to the osteopontin family and sits within the SIBLING family group at HGNC. Check the datasheet of any product for its validated reactivity.
Related secreted phosphoproteins, cytokines and receptors connected to osteopontin biology, with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P10451; product specifications from Assay Genie datasheets.