Identification and Developmental Expression of New Biomineralization Proteins in the Sea Urchin Strongylocentrotus Purpuratus

Dev Genes Evol. 2002 Oct;212(9):419-31. doi: 10.1007/s00427-002-0261-0. Epub 2002 Sep 7.


The endoskeleton of the sea urchin larva is a network of calcareous rods secreted by primary mesenchyme cells (PMCs). In this study, we identified seven new biomineralization-related proteins through an analysis of a large database of gene products expressed by PMCs. The proteins include three new spicule matrix proteins (SpSM29, SpSM32, and SpC-lectin), two proteins related to the PMC-specific cell surface glycoprotein MSP130 (MSP130-related-1 and -2), and two novel proteins (SpP16 and SpP19). The genes encoding these proteins are expressed specifically by cells of the large micromere-PMC lineage and are activated zygotically beginning at the blastula stage, prior to PMC ingression. Several of the mRNAs show regulated patterns of expression within the PMC syncytium that correlate with the pattern of skeletal rod growth. This work identifies new proteins that may regulate the process of biomineralization in this tractable model system.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Blotting, Northern
  • Cytoskeletal Proteins / isolation & purification
  • Cytoskeletal Proteins / metabolism
  • Extracellular Matrix Proteins / biosynthesis
  • Extracellular Matrix Proteins / genetics
  • Extracellular Matrix Proteins / isolation & purification*
  • Gene Expression Regulation, Developmental*
  • Glycoproteins / biosynthesis
  • Glycoproteins / genetics
  • Glycoproteins / isolation & purification
  • In Situ Hybridization
  • Mesoderm / physiology*
  • Molecular Sequence Data
  • Morphogenesis / genetics
  • Phylogeny
  • RNA, Messenger / analysis
  • Sea Urchins / embryology
  • Sea Urchins / genetics*
  • Sequence Homology, Amino Acid


  • Cytoskeletal Proteins
  • Extracellular Matrix Proteins
  • Glycoproteins
  • RNA, Messenger
  • SM50 protein, sea urchin