Certain behaviors are considered complex traits that are influenced by the expression of multiple pleiotropic genes. Looking at Drosophilia melanogaster, we are able to look at the effects of the hypomorphic disruption of the early developmental gene Semaphorin-5c. During the Benzaldehyde avoidance assay, flies were put into a vial and the odor was introduced on a cotton swab. The number of flies that were present in the vial further away from the odor were recorder every five seconds for one minute. This was only the first method. The following methods included a quantitative complementation test, phenotypic reversion through P-element excision, Transgenic rescue, whole-mount immunohistochemistry, the antibody that was obtained, microscopy, morphometric analysis, transcriptional profiles, and Epistasis. The results were as followed. A P-element insertion near the Sema-5c gene concluded in aberrant olfactory behavior. P[GT1]-element disruption of Sema-5c resulted in the presence of the smell-impaired phenotype. Neuroanatomical consequences of disruption of the Sema-5c gene. Sema-5c gene also altered genome wide expression levels. All of these results conclude that the hypomorphic mutation of an early development gene has a consequence of genome wide transcriptional problems and alterations in the brain structure which results in the impairment of adult behavior.
Heather Davis
41347173
Reference
Rollmann, Stephanie M., Yamamoto, Akihiko. 2007. The Early Developmental Gene Semaphorin 5c Contributes to Olfactory Behavior in Adult Drosophila. http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1894621
