Send to

Choose Destination
See comment in PubMed Commons below
Connect Tissue Res. 2003;44 Suppl 1:33-40.

Six genes expressed in bones and teeth encode the current members of the SIBLING family of proteins.

Author information

Matrix Biochemistry Unit, Craniofacial & Skeletal Diseases Branch, NIDCR, NIH, HHS, Bethesda, Maryland 20892-4320, USA.


Bone sialoprotein (BSP), dentin matrix protein 1 (DMP1), dentin sialophosphoprotein (DSPP), enamelin (ENAM), matrix extracellular phosphoglycoprotein (MEPE), and osteopontin (OPN) are glycophosphoproteins expressed in bones and/or teeth. Direct comparison of their amino acid sequences do not suggest that they belong to a single genetic family, but a detailed analysis of their chromosomal location and gene structure does. Analysis of human brain mRNA by RT-PCR has led to the discovery of two additional exons thereby making it more convincing that MEPE is a member of the SIBLING (Small Integrin-Binding LIgand, N-linked Glycoprotein) family. We propose that the members of this SIBLING family are extended, flexible proteins in solution that can facilitate the formation of a number of different complexes. For example, OPN can bridge complement Factor H to either an RGD-dependent integrin or to CD44 forming a membrane-bound complex that actively suppresses the alternate complement pathway. Two possible mechanisms for inhibiting the lytic pathway of alternate complement are presented.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Loading ...
    Support Center