How comb jellies stay coordinated

Grape-sized gelatinous creatures called comb jellies move through the oceans using eight rows of long cilia. How the paddle-like cilia all beat in unison has long befuddled scientists, but now a University of Tsukuba–led team has discovered a protein that facilitates this coordination.

The researchers removed the comb plates that run along each row of cilia and extracted a protein they named CTENO64. Blocking expression of this protein led to the formation of misaligned cilia that beat out of sync with one other, causing abnormal locomotion of the comb jellies.

Searching through gene databases, the researchers could not find any variants of the CTEN064 protein in the genomes of any animals besides comb jellies. The findings thus provide an exquisite example of the ‘hidden biology’ still to be explored in comb jellies and other exotic creatures with unique evolutionary features.