Discipline: Biological Sciences
Subcategory: Biochemistry (not Cell and Molecular Biology and Genetics)
Room: Exhibit Hall
James - Pontifical Catholic University of Puerto Rico
The Aryl Hydrocarbon Receptor (AHR) is a ligand-activated transcription factor which is responsible for sensing planar aromatic hydrocarbons, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in our environment. In the absence of ligand, AHR is in the cytosol and when exposed to TCDD, it moves to the nucleus where it regulates the expression of a large battery of genes which many of these encode detoxifying enzymes but some influence mitochondrial-associated proteins. Previous RNAseq data suggest that loss of AHR impacts the expression of genes that encode subunits of the mitochondrial calcium uniporter (MCU), most notable the Micu2 subunit. Interestingly, loss of the Translocator Protein (TSPO), an outer mitochondrial membrane protein, also impacts Micu2 expression. We hypothesized that crosstalk between AHR and TSPO regulates Micu2 expression and mitochondrial calcium loading. To test our hypothesis, we used wild type (WT), AHR-/-, and TSPO-/- mouse lung epithelial cells (MLE-12). These cells lines were treated with PK11195, (a TSPO ligand), TCDD, and both concurrently or their respective vehicles solvents (i.e. ethanol and DMSO). Following a 6-hour exposure, RNA was isolated and analyzed for the expression of genes that encode MCU subunits encoding genes. Results showed loss of TSPO and AHR caused a decrease in Micu2 expression. In contrast, treatment with TCDD or PK11195 did not alter Micu2 expression. These results suggest that there could be possible crosstalk between AHR and TSPO, playing a crucial role in regulating the expression of genes that encode MCU complex subunits, such as Micu2 critical to mitochondrial calcium homeostasis.
Funder Acknowledgement(s): NIH Grant: 5R25ES025060-08
Faculty Advisor: Dr. LaPres, email@example.com
Role: I worked in the Dr. John LaPres laboratory in which I was in charge of different laboratory techniques such as CRISPR/Cas9 knockout, MLE-12 cell culture, counting, and treatments, RNA extraction and isolation, determination of RNA concentration, cDNA synthesis, and real-time qPCR in order to research the possible effects that AHR and TSPO could have in the MICU2 subunit expression which is a part of the mitochondrial calcium uniporter complex protein that regulates the mitochondrial calcium uptake which can affect calcium homeostasis increasing mitochondrial dysfunction and thus metabolic disorders.