The phosphocreatine shuttle of sea urchin sperm: flagellar creatine kinase resulted from a gene triplication.

AUTOR(ES)

Wothe, D D

RESUMO

TCK, the creatine kinase (ATP:creatine N-phosphotransferase) from sperm flagella of the sea urchin Strongylocentrotus purpuratus, is a Mr 145,000 axonemal protein that is employed in energy transport. Its amino acid sequence was obtained by analysis of fragments from cyanogen bromide digestion and by sequencing cDNA clones from two sea urchin testis libraries. TCK contains three complete but nonidentical creatine kinase segments joined by regions of sequence that are not creatine kinase-like and flanked by unique amino and carboxyl termini. Each creatine kinase segment is homologous to vertebrate creatine kinases of both muscle and brain types, and all three repeats contain the essential active-site cysteine. The sequence differences among repeats suggest an ancient gene triplication, around the time of the chordate-echinoderm divergence. The echinoderm, with a unique creatine kinase in sperm, arginine kinase in eggs, and both phosphagen kinases in somatic cells, may represent a preserved branch point in evolution, and TCK may be a relic of this event.

Documentos Relacionados

• Assembly of chick brain tubulin onto flagellar microtubules from Chlamydomonas and sea urchin sperm.
• Protein kinase C is present in human sperm: possible role in flagellar motility.
• STRUCTURE OF THE CHROMATIN IN SEA URCHIN SPERM*
• A monoclonal antibody against the dynein IC1 peptide of sea urchin spermatozoa inhibits the motility of sea urchin, dinoflagellate, and human flagellar axonemes.
• The nucleotide sequence of the gene encoding the sperm specific histone subtype H2B-1 from the sea urchin Strongylocentrotus purpuratus.