Bridging the GAP(DH): measuring baseline levels of MOR-1K gene expression in mouse neuroblastoma cells (2016)

Undergraduate: Marc Gutierrez

Faculty Advisor: Andrea Nackley
Department: Chemistry

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Opioid-induced hyperalgesia (OIH) is a clinical pain condition in which opioid analgesics like morphine increase a patient¿¿¿s pain sensitivity. The results from previous genetic association, in vitro, and behavioral studies support the notion that MOR-1K, a functional genetic variant of the mu-opioid receptor, contributes to OIH in genetically susceptible individuals. My overall research project is focused on determining the effect of a single nucleotide variation in the mouse MOR-1K gene on the expression of the mRNA for this receptor. To do this, the baseline MOR-1K mRNA expression levels in mouse neuroblastoma cells had to be determined both in the presence and absence of morphine. Identical groups of these cells were treated with either 10 ¿¿M morphine or fresh cell media for 5 min, 10 min, and 20 min intervals. The reference group received no treatment. mRNA samples from these cells were then harvested and converted to purified cDNA. Real-time PCR was used to determine the levels of MOR-1K expression in each one of the sample groups relative to the expression of GAPDH, a positive control gene known to be expressed in these cells. Preliminary results show that relative MOR-1K expression levels decrease with increased morphine exposure. Upon further analysis, however, the absolute expression of MOR-1K actually increased, but GAPDH expression increased even more. My current research is focused on testing other positive control genes to replace GAPDH.