Meeting Abstract

P3.25  Saturday, Jan. 5  Homeobox gene expression during zooid development in colonies of the marine bryozoan Membranipora membranacea TEMKIN, M H*; MISERCOLA, B A; St. Lawrence Univ, Canton, NY; St. Lawrence Univ, Canton, NY mtemkin@stlawu.edu

During animal development, regions of the body along the anteroposterior axis are specified through the biochemical milieu established by transcription factors that are coded for by the homeobox genes. The characterization of homeobox genes from a variety of species has lead to the identification of a highly conserved region of about 60 amino acids that represents the homeodomain. The homeodomain of these proteins allows the transcription factors to bind to the DNA. The homeobox genes involved in anteroposterior body patterning have been well characterized in model organisms, such as Drosophilia, mouse, and chicken. However, our knowledge of homoebox genes in many other organisms, including the bryozoans, is very limited. Bryozoans are a large group of colonial invertebrates that live in marine and freshwater habitats and collect food particles with a retractable crown of ciliated tentacles. As each new member of a bryozoan colony forms by asexual budding, it develops structures along its own proximal-distal axis. An essential first step in understanding how each member of a bryozoan colony develops its own body pattern is the characterization of homeobox gene expression during the differentiation of asexually budded individuals. Here we present data on the protein coding sequences of three homeobox genes expressed during the development of individuals in colonies of the marine bryozoan Membranipora membranacea which contain homeodomains with similarites to Lox 5/Hox B7, GBX 2, and Hox A4.