|Ref Sequence ID||NP_776612.1|
|Protein Existence Status||Reviewed: Experimental evidence at protein level|
|Presence in other biological fluids/tissue/cells||blood, urine, seminal fluid|
|Protein Function||Inhibition of ectopic calcification, bone remodelling, cancer metastasis and immune modulatory functions; act as an opsonin, as it binds directly to several bacterial strains leading to enhanced phagocytosis by macrophages; can induce Th1 type immunity by inducing interleukin-12 expression in macrophages|
|Biochemical Properties||resistant to proteolysis by neonatal gastric juice;very resistant to harsh conditions; e.g., heat treatment at 90 C has no effect on the post-translational modifications decorating the protein;Proteolytic cleavage close to the integrin binding motifs has been demonstrated to increase the integrin binding properties of OPN; Milk OPN is a very acidic protein due to a high degree of negatively charged amino acids and the many phosphorylations decorating the protein;|
|Significance in milk||OPN plays a role in the development of the infant and could provide an important immunological signal during development; OPN, which possess known cytokine-like properties, was the most abundantly expressed when compared with the expression of 240 cytokine related genes in human milk; involved in mammary gland development and differentiation; bind and form soluble complexes with calcium ions which together with especially the caseins, could inhibit unintentional precipitation of amorphous calcium phosphate in milk; act as a transporter of these immunomodulating and antimicrobial proteins to their site of action and to protect them from proteolysis|
|PTMs||Phosphorylated glycoprotein; ~25 phosphates distributed over 36 potential sites in human milk osteopontin; ~22 phosphates distributed over 28 potential sites in bovine milk osteopontin; Bovine milk OPN contains three O-glycosylated threonine residues close to the integrin binding motifs; The glycan structures on human milk OPN have been shown to consist of large fucosylated N-acetyllactosamine units; the carbohydrates on bovine OPN consist of a disialylated GalNAc-galactose cores|
| Site(s) of PTM(s) |
|>sp|P31096|OSTP_BOVIN Osteopontin OS=Bos taurus OX=9913 GN=SPP1 PE=1 SV=2|
MRIAVICFCL LGIASALPVK PT S*23S*24GS*26S*27EEK QLNNKYPDAV ATWLKPDPSQ KQTFLAPQN S*60VS*62S*63EETDDNK QNTLP S*76KS*78NES*81PEQTDDLDD DDDNS*95QDVN S*100NDS*103DDAETTDDPDHS*115DESHHS*121DES*124DEVDFPT*131DIPTIAVFT*140 PFIPT*145ESANDGRGDSVAYGLKSRSKKFRRSNVQSPDAT*178EE DFTS*184HIES*188EE MHDAPKKTSQLTDHS*205KETNS*210 SELSKELTPK AKDKNKHSNL IES*233QENSKLS*240 QEFHS*245LEDKLDLDHKS*256EEDK HLKIRIS*267HEL DS*272AS*274SEVN
|Predicted Disorder Regions||(1-278)|
|TM Helix Prediction||No TM helices|
|PDB ID||2dxr, 2dxy, 2dyx, 2e0s, 2e1s, 2fa7, 2g93, 2h4i, 2hca, 2md1, 2md2, 2md3, 2md4, 2nuv, 2nwj, 2o1l, 2o51, 2ocu, 2p1s, 2px1, 2q8j, 2qje, 2r71, 2r9j, 2zmb, 3cfl, 3ci8, 3crb, 3e9x, 3iaz, 3ib0, 3ib1, 3ib2, 3k0v, 3kj7, 3mjn, 3mjn, 3o97, 3rgy, 3sdf, 3taj, 3tod, 3tus, 3u72, 3u8q, 3ugw, 3uk4, 3usd, 3v5a,3vdf, 4dig, 4dxu, 4fim, 4fjp, 4for, 4g2z, 4g77, 4g8h, 4grk, 4n6p, 4ned, 4oqo, 5cry, 5hbc, 1blf, 1lfc, 1nkx, 1sdx, 1y58, 2alu, 2ays, 2b65, 2doj, 2dp8, 2dqv, 2ds9, 2dsf, 2dvc, 2dwa, 2dwh, 2dwi, 2dwj,|
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