My Research Interest

All cells have internal biochemical mechanisms to deal with stress factors that may disrupt homeostasis. Many Inverberates are constantly exposed to a variety of stressors in different degrees. It is thus not hard to imagine that their biochemical weaponry is quite extensive to deal with these disruptions in order to protect their cellular machinery.

Stressors are events that disrupt the internal, extracellular environment and as such affect the surrounding cells, creating homeostatic imbalances. Humans tend to avoid many of such environmental stressors by their behavioral responses. Aquatic invertebrates live in an external enviroment whose composition can fluctauate drastically depending on the governing ecological influences. Considering that their escape mechanism is often slow to sluggish, the exposure to stressors can become very chronic. The typical stressors an aquatic invertebrate experiences are oxygen deprivation, pollution and changes in salt content or osmolarity of the medium.

Xenobiotics, suchs as heavy metals and pesticides ( and other enviromental challenges such as hypoxia, changes in salinity or osmolarity) are known to cause alterations in gene expression , resulting in repression or induction of protein production . The project will examine the responses of a few model invertebrates to such environmental stimuli by means of their cellular expression of mRNA.

Invertebrates provide unique research opportunities since there are literally thousands of available species. Although their physiology has been researched extensively, for many such species, the molecular aspects of the phsyiology and biochemistry remains largely unexplored. The disadvantage is that knowledge of the cDNA ( the reverse mRNA) sequences of the proteins to be investigated is unknown as well. The first part of the research is hence to isolate their mRNA, generate cDNA’s  and sequence the putative cDNA’s of interest. Once we obtain their sequence information, specific primers can be constructed to investigate their cellular expression during environmental stress. This requires not only lab research, but a bio-informatics computer approach to data mine the gene banks, find similar proteins and look for conserved sequences in order to generate the correct initial primers needed for PCR amplification of the desired mRNA’s.

Dr. C. Doumen - 2010