Structure of the Spec1 gene encoding a major calcium-binding protein in the embryonic ecoderm of the sea urchin, Strongylocentrotus purpuratus

The authors have identified and characterized the structure of the Spec1 gene in the sea urchin Strongylocentrotus purpuratus . Spec1 transcripts, the predominant mRNAs of the family are heterogeneous in their 3' untranslated sequences but code for a single protein, recently shown to be a calcium-binding protein. Spec complementary DNA clones were used to isolate genomic clones from two lambda libraries. These genomic clones comprise a 41 kb (kb = 10 super(3) bases or base-pairs) region of the S. purpuratus) genome and contain a Spec1 gene closely linked to another Spec gene, Spec2c . The Spec1 gene is 10 multiplied by 3 kb in length and contains six exons. There appears to be a single polymorphic Specl gene in the sea urchin genome. The authors used S sub(1) protection and primer extension procedures to map the 5' end of the Specl) gene.