Related Experiment Video
Updated: Aug 9, 2026

Embryo Microinjection and Electroporation in the Chordate Ciona intestinalis
Published on: October 16, 2016
A wide-range phylogenetic analysis of Zic proteins: implications for correlations between protein structure
Jun Aruga1, Akiko Kamiya, Hirokazu Takahashi
1Laboratory for Comparative Neurogenesis, RIKEN Brain Science Institute, Wako 351-0198, Japan. jaruga@brain.riken.jp
Abstract:
We compared Zic homologues from a wide range of animals. Striking conservation was found in the zinc finger domains, in which an exon-intron boundary has been kept in all bilateralians but not cnidarians, suggesting that all of the bilateralian Zic genes are derived from a single gene in a bilateralian ancestor. There were additional conserved amino acid sequences, ZOC and ZF-NC. Combined analysis of the zinc finger, ZOC, and ZF-NC revealed the presence of two classes of Zic, based on the degree of protein structure conservation. The "conserved" class includes Zic proteins from the Arthropoda, Mollusca, Annelida, Echinodermata, and Chordata (vertebrates and cephalochordates), whereas the "diverged" class contains those from the Platyhelminthes, Cnidaria, Nematoda, and Chordata (urochordates). The result indicates that the ancestral bilateralian Zic protein had already acquired an entire set of conserved domains, but that this was lost and diverged in the platyhelminthes, nematodes, and urochordates.
Related Concept Videos
Evolutionary Relationships through Genome Comparisons
Conservation of Protein Domains Over Different Proteins
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
Structural Protein Function
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...
Structural Protein Function
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...
Microbial Phylogeny
Conservation of Protein Domains
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...

