Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Brianna L. Scotland - University of the Virgin Islands
Co-Author(s): Robert S. Jones, University at Buffalo, Buffalo, New York; Marilyn E. Morris, University at Buffalo, Buffalo, New York
Monocarboxylate Transporter 6 (Mct6; Slc16a5) is a member of the SLC16 gene comprised of 14 isoforms. None of the characteristics of the proton dependent Mcts 1-4 overlap with Mct6, making it unique. Mct6 activity is dependent on pH and membrane potential. All substrates currently identified for Mct6 are drugs (i.e. bumetanide, nateglinide, and probenecid). However, no endogenous substrates or function of Mct6 are known, making it an “orphan” transporter. Mcts are essential in metabolic processes such as glycolysis, pH regulation, and fatty acid absorption. Further characterization of Mct6 may lead to a new drug target or drug delivery mechanism that may be utilized in the clinic. The aims of this study were to verify the absence of Mct6 gene expression in a knockout (KO) mouse model using qRT-PCR and to characterize the Mct6 gene expression profile in normal wildtype (WT) mice. Our hypothesis was Mct6 is majorly expressed in tissues involved in drug absorption and elimination (such as the kidney, liver, and intestine) and is not expressed in any tissue in the homozygous knockout mouse model (Mct6 KO). Several tissues were harvested from (N = 4) Mct6 KO and WT mice. These tissues included the liver, kidney, colon, duodenum, jejunum, ileum, lung, and brain. Total RNA was isolated and purified from each tissue using a commercially available kit. The RNA was then reverse-transcribed to cDNA, which was utilized in the qRT-PCR analyses. The analyses confirmed that Mct6 is expressed in major tissues such as the liver, kidney, colon, ileum, and jejunum. KO tissues resulted in ≥ 90% reduction in Mct6 expression. Mct6 gene expression was undetectable in both the KO and WT lung, brain, and duodenum tissues. Mct6 may play an essential role in drug absorption and elimination as a result of its expression profile. All of the Mct6 KO mice had relatively no gene expression, thus confirming its suitability as an in vivo model to study this transporter. Despite the presence of mRNA expression in major tissues, this may or may not correlate to protein expression possibly due to post-transcriptional regulation. Further studies are necessary looking into protein expression and activity prior to confirming Mct6’s role in vivo in particular mammalian tissues.Not Submitted
Funder Acknowledgement(s): NIH grant DA-023223 MARC grant #5T34GM008422
Faculty Advisor: Dr. Marilyn Morris, firstname.lastname@example.org
Role: I was heavily involved in the many processes such s tissue homogenization, mRNA isolation, and purification, and converting RNA to cDNA. I also conducted flash gels on my samples. Data from qRT-PCR analyses allowed to analyze and interpret my result which, with assistance, allowed me to develop several graphs and form a conclusion with literature support.