Downregulation of Glis3 in INS1 cells exposed to chronically elevated glucose contributes to glucotoxicity-associated β cell dysfunction

Chronically elevated levels of glucose are deleterious to pancreatic β cells and contribute to β cell dysfunction, which is characterized by decreased insulin production and a loss of β cell identity. The Krüppel-like transcription factor, Glis3 has previously been shown to positively regulate insulin transcription and mutations within the Glis3 locus have been associated with the development of several pathologies including type 2 diabetes mellitus. In this report, we show that Glis3 is significantly downregulated at the transcriptional level in INS1 832/13 cells within hours of being subjected to high glucose concentrations and that diminished expression of Glis3 is at least partly attributable to increased oxidative stress. CRISPR/Cas9-mediated knockdown of Glis3 indicated that the transcription factor was required to maintain normal levels of both insulin and MafA expression and reduced Glis3 expression was concomitant with an upregulation of β cell disallowed genes. We provide evidence that Glis3 acts similarly to a pioneer factor at the insulin promoter where it permissively remodels the chromatin to allow access to a transcriptional regulatory complex including Pdx1 and MafA. Finally, evidence is presented that Glis3 can positively regulate MafA transcription through its pancreas-specific promoter and that MafA reciprocally regulates Glis3 expression. Collectively, these results suggest that decreased Glis3 expression in β cells exposed to chronic hyperglycemia may contribute significantly to reduced insulin transcription and a loss of β cell identity.

Experience conducting a community-engaged student research project involving an underrepresented community: A reflective essay

Recruiting racially and ethnically underrepresented participants into genetics research studies has been challenging. While many institutions have taken steps to address the inequity in genetics research, genetic counseling training programs have the chance to inspire students to engage with underrepresented communities through utilizing different research methodologies. These methodologies can help students focus on research projects that increase access to genetics services and improve clinical care. Community-engaged research (CER) presents a pedagogical approach to enhance service-learning opportunities for students. Furthermore, it allows students to develop practical research skills for doing research with the community, rather than on the community. CER is a collaborative community-academic partnership that leads to mutual benefit and outcomes such as inclusion and engagement of the community in research, building trust and relationships, and increasing cultural awareness and exposure. In addition, CER can be used to address research and healthcare inequities by providing opportunities for genetics professionals and trainees to work closely with underrepresented populations. We aim to highlight the opportunities CER provides to students, mentors, and faculty within the context of graduate research in genetic counseling training from the experiences of a student and an educator. In addition, we hope to emphasize the necessity for projects like these to address the gaps in participation of underrepresented patient populations in research and identify areas that are mutually beneficial to improve health outcomes, patient care experiences, access, and service delivery. This reflective essay illustrates the completion of a CER project that was developed in collaboration with community members to address gaps in clinical genetics services in Indigenous healthcare.