(full paper is archived in the Miller Library)
Title: Expression of exogenous DNA in squid giant fiber lobe neurons
Student Author(s): Cho, Albert W.
Faculty Advisor(s): Gilly, William
Location: Final Papers Biology 175H
Date: June 1992
Abstract: Although most previous research has not been successful in getting mature, differentiated neurons to express exogenous DNA, this has reportedly been done in a variety of neuron types in Aplysia californica using a RSV promoter/enhancer sequence. This study attempted to express the lacZ gene from Escherichia coli in the giant fiber lobe (GFL) neurons of squid using this promoter/enhancer. No expression of the B-galactosidase enzyme was detected in GFL cells or the Aplysia neurons when the cells were injected with the plasmid, but B-galactosidase activity was assayed in neuroblastoma cells. A probable reason for non-expression of the plasmid in the Aplysia may be ineffective injection techniques. the non-expression in the GFL cells may be due to either the injection process or the inability of the cell to be induced by the RSV promoter. However, one additional factor involved in expression of exogenous DNA was found. In looking at another study done on GFL cells, it was found that heat shock increassed expression of Na channels. The exact mechanism that is affected to produce this effect from endogenous genes is unknown, but the effect heat shock may have on exogenous DNA expression cannot be ignored. And given the differences between the Aplysia and the squid systems, more studies on the effect of heat shock on these systems must be done before any definite conclusions can be drawn.