title: Sequence, annotation and developmental expression of the sea urchin Ca(2+) -ATPase family.
abstract: Whole genome sequence data permit the study of protein families regulating cellular homeostasis during development. Here we present a study of the sea urchin Ca(2+)-ATPases made possible by the Sea Urchin Genome Sequencing Project. This is of potential interest because adult sea urchins, their gametes and embryos live in the relatively high Ca(2+) concentration of 10 mM. Three Ca(2+)-ATPases regulate Ca(2+) levels in animal cells: plasma membrane Ca(2+)-ATPase (PMCA), sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA) and secretory pathway Ca(2+)-ATPase (SPCA). The primary structures of Sp-PMCA and Sp-SERCA in the sea urchin, Strongylocentrotus purpuratus (Sp), have been published. Here, we present the primary structure of Sp-SPCA, which is 912 amino acids and has 66% identity and 80% similarity to human SPCA1. Southern blots and genome analysis show that Sp-SPCA is a single copy gene. Each Sp Ca(2+)-ATPase is highly conserved when compared to its human ortholog, indicating that human and sea urchin share structurally similar energy driven Ca(2+) homeostasis mechanisms that have been maintained throughout the course of deuterostome evolution. Annotation using the assembled sea urchin genome reveals that Sp-SPCA, Sp-PMCA and Sp-SERCA have 23, 17 and 24 exons. RT-Q-PCR shows that transcripts of Sp-SPCA are at low levels compared to Sp-PMCA and Sp-SERCA. Gradual increases in Sp-PMCA and Sp-SERCA mRNA begin at the 18 hour hatched blastula stage and peak 4-5-fold higher by 25 h at the mid to late blastulae stage.
authors.affiliation: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093-0202, USA. jayantha_gunaratne@etc.a-star.edu.sg
authors.forename: H
authors.initials: H
authors.lastname: Jayantha Gunaratne
authors.forename: Victor D
authors.initials: VD
authors.lastname: Vacquier
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D000252:Calcium-Transporting ATPases / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D053499:Plasma Membrane Calcium-Transporting ATPases / Q000737:chemistry / Q000235:genetics; D017434:Protein Structure, Tertiary; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000737:chemistry / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D047270:Strongylocentrotus purpuratus / Q000196:embryology / Q000201:enzymology* / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D053499:Plasma Membrane Calcium-Transporting ATPases; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D000252:Calcium-Transporting ATPases