Alpha-s1 casein (IPR026999)

Short name: Alpha-s1_casein

Overlapping homologous superfamilies


Family relationships


Alpha-S1-casein plays an important role in the capacity of milk to transport calcium phosphate [PMID: 21789179]. It is also required for efficient export of the other caseins from the endoplasmic reticulum and plays a key role in early steps of casein micelle biogenesis and casein transport in the secretory pathway [PMID: 20704729, PMID: 10504344].

Caseins [PMID: 3074304] are the major protein constituent of milk. In milk, caseins interact with calcium phosphate, forming large stable colloidal particles termed micelles. These micelles make it possible to maintain a supersaturated calcium phosphate concentration in milk, providing the newborn with sufficient calcium phosphate for the mineralisation of calcified tissues [PMID: 7619062]. Caseins can be classified into two families; the first consists of the kappa-caseins, and the second groups the alpha-s1, alpha-s2, and beta-caseins. The alpha/beta caseins are a rapidly diverging family of proteins [PMID: 16386026, PMID: 3952000]. However two regions are conserved: a cluster of phosphorylated serine residues and the signal sequence.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0005576 extracellular region

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.