Evolution of Hox gene expression and function and the effect on limb specification in arthropods
- Author(s): Hsia, Cheryl Chih-Jui
- et al.
Many common sets of genes are used to generate diverse animal body plans. One set of these genes are the Hox genes, transcription factors that specify segmental identity along the anterior-posterior axis of animals in early development. Many studies have been carried out to uncover how the evolution of Hox genes and Hox gene function may have precipitated the evolution of diverse body plans. I carried out functional assays in Drosophila melanogaster embryos to explore whether changes in protein sequence may have facilitated the divergence of six-legged insects from multi-legged crustaceans. I developed fluorescent immunohistochemistry and double in situ hybridization methods in the crustacean, Artemia franciscana, to further clarify the HOX expression patterns in the trunk. From these studies, I found an example of a Hox gene capable of homeotic function, but inhibited from expression and presumably, inhibited from conferring segmental identity. This loss of segment identity function may contribute to the overall morphological body plan of Artemia to ensure the development of limbs throughout the trunk