Over one-half billion years of head conservation? Expression of an ems class gene in Hydractinia symbiolongicarpus (Cnidaria: Hydrozoa).

ABSTRACT: We report the isolation of an empty spiracles class homeodomain-containing gene, Cn-ems, from the hydrozoan Hydractinia symbiolongicarpus, the first gene of this class characterized in a lower metazoan. Cn-ems was found to be expressed in the head of gastrozooids, specifically in endodermal epithelial cells of the taeniolae of the hypostome. Cn-ems is not expressed in gonozooids, which lack taeniolae. Experimental conversion of the posterior region of the planula larva into head structures up-regulates expression of the gene. These findings establish that the association of ems-class genes with head structures preceded the evolution of bilateral symmetry.

SUBMITTER: Mokady O 

PROVIDER: S-EPMC19894 | biostudies-literature | 1998 Mar

REPOSITORIES: biostudies-literature