Small proline-rich protein/late cornified envelope protein (IPR026075)

Short name: SPRR/LCE

Overlapping homologous superfamilies


Family relationships


The genes that code for small proline-rich region (SPRR) proteins and late cornified envelope (LCE) proteins are found in clusters as part of the epidermal differentiation complex [PMID: 15854049].

SPRRs (small proline-rich proteins) are involved in the assembly of the cornified cell envelope, a specialised structure beneath the plasma membrane of keratinocytes [PMID: 21248766]. This structure is essential for the barrier properties of the skin. At least four SPRRs have been described: SPRR1, -2, -3, and -4 [PMID: 12584609]. Cornifin (SPRR1) first appears in the cell cytosol, but ultimately becomes cross-linked to membrane proteins by transglutaminases. This results in the formation of an insoluble envelope beneath the plasma membrane [PMID: 8601731].

Late cornified envelope (LCE) proteins are also cornified envelope precursors that have protein crosslinking functions similar to SPRR. There are several LCE proteins which can be classified in different groups. Regulatory diversification within groups may permit specific responsiveness to environmental challenge [PMID: 15854049].

Contributing signatures

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