Primary Information
BoMiProt ID	Bomi119
Protein Name	Osteopontin
Organism	Bos taurus
Uniprot ID	P31096
Milk Fraction	Whey
Ref Sequence ID	NP_776612.1
Aminoacid Length	278
Molecular Weight	30904
FASTA Sequence	Download
Gene Name	SPP1
Gene ID	281499
Protein Existence Status	Reviewed: Experimental evidence at protein level
Secondary Information
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) N-glycosylation, O-glycosylation, Phosphorylation	>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)
DisProt Annotation
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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