Olivia Aguirre
Pronouns: she/her
Research Mentor(s): Sebastian Vishnopolska
Research Mentor School/College/Department: Department of Human Genetics / Medicine
Program:
Authors: Olivia Aguirre, Sebastian Vishnopolska
Session: Session 7: 4:40 pm – 5:30 pm
Poster: 62
Abstract
ARID1A (AT-rich interaction domain 1A) is a tumor suppressor gene that encodes a member of the chromatin remodeler complex SWI/SNF. Truncating mutations in this gene were linked to a predisposition to colon and endometrial cancers. Previous studies have linked ARID1A with the mismatch repair system (MMR) function, which is a group of proteins (MLH1, MSH2, MSH6 and PMS2) that corrects nucleotide mismatch errors in the DNA. Heterozygous mutations in the MMR genes cause a hereditary cancer predisposition syndrome called Lynch syndrome. Our lab previously demonstrated that MMR deficient cells are resistant to nucleotide analog 6TG (6-thioguanine), which causes nucleotide mismatches during DNA replication. MMR proficient cells detect the mismatches produced by 6TG and induce apoptosis, while MMR deficient cells survive the treatment. We hypothesize that ARID1A deficient cells also have a resistance to 6TG. To execute this, our first objective will be to develop an ARID1A deficient cell line model. We began by using CRISPR-Cas9 technology to target and truncate exons 2 and 18 of the ARID1A endogenous locus of HAP1 cells. Then, we isolated individual cells to get clonal populations of knock-out (KO) cells. To confirm proper KO DNA was extracted, we amplified the targeted loci by PCR and sequenced it to identify presence or absence of indels. Later, ARID1A-KO confirmed HAP1 cells were tested for resistance/susceptibility to 6TG. Following these steps we aim to obtain a standard cell line for testing future ARID1A mutations that will allow for a deeper understanding on ARID1A connection to both MMR and cancer predisposition.
