Abstract.
The evolutionary relationship of muscle and nonmuscle actin isoforms in deuterostomia was studied by the isolation and characterization of two actin genes from the cephalochordate Branchiostoma lanceolatum and two from the hemichordate Saccoglossus kowalevskii The Branchiostoma genes specify a muscle and a nonmuscle actin type, respectively. Together with earlier results on muscle actins from vertebrates and urochordates, a N-terminal sequence signature is defined for chordate muscle actins. These diagnostic amino acid residues separate the chordates from the echinoderms and other metazoa. Although the two Saccoglossus actins characterized so far lack the diagnostic residues, in line with the presumptive phylogenetic position of hemichordates outside the chordates, a definitive conclusion can only be expected once the full complement of actin genes of Saccoglossus is established. Comparison of the intron patterns of the various deuterostomic actin genes shows that intron 330-3, which is present in all vertebrate genes, is conspicuously absent from nonvertebrate genes. The possible origin of this intron is discussed.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Author information
Authors and Affiliations
Additional information
Received: 4 July 1997 / Accepted: 29 August 1997
Rights and permissions
About this article
Cite this article
Bovenschulte, M., Weber, K. Deuterostomic Actin Genes and the Definition of the Chordates: cDNA Cloning and Gene Organization for Cephalochordates and Hemichordates. J Mol Evol 45, 653–660 (1997). https://doi.org/10.1007/PL00006269
Issue Date:
DOI: https://doi.org/10.1007/PL00006269