Robledo, J. et al. (2019) International Worm Meeting "Identification of transcriptional regulators impacted by a glucose-supplemented diet in C. elegans."

Leguizamo, Isai, Robledo, J., Padilla, Pamela, Azad, Rajeev

[International Worm Meeting, 2019]

Patients with type 2 diabetes display metabolic abnormalities including, hyperglycemia, increase in free fatty acids, and insulin resistance. These metabolic abnormalities induce severe and ultimately detrimental human health issues such as cardiovascular disease and neuropathy. Changes in gene expression is an underlying factor that contributes to the physiological changes associated with diabetes. However, little is understood about how factors such as hyperglycemia or a sugar-supplemented diet impacts gene expression. We use the genetic model Caenorhabditis elegans to study the impact a glucose-supplemented diet has on various biological processes including physiology and gene expression. Previously, we showed that a glucose-supplemented diet increases lipid composition, and significantly alters the transcriptome profile (RNA-sequencing studies). From our transcriptomic analysis, we identified 140 gene expression regulators altered in response to a glucose-supplemented diet. We determined the acs-2 gene, which encodes an acyl-CoA synthetase, is a glucose-responsive gene; this was shown by RNA-sequencing analysis, the acs-2::GFPreporter strain, and quantitative RT-PCR. Here, we developed a targeted RNA interference (RNAi) screen to identify the transcriptional regulators that respond to a glucose diet using the acs-2::GFPreporter strain. We used RNAi to knock-down transcriptional regulators, many of which are known to be differentially expressed by a glucose diet, to identify those that modulate acs-2 expression in a glucose-supplemented diet dependent manner. In total, we assayed 140 transcriptional regulators. Results from this RNAi screen will be presented. Together, these studies add to our understanding of the physiological, transcriptional, and molecular changes that occur in response to a glucose supplemented diet.

Robledo, Jose et al. (2021) International Worm Meeting "Identification of transcriptional regulators impacted by a glucose-supplemented diet in C. elegans"

Burks, David, Robledo, Jose, Padilla, Pamela, Song, Luhua, Azad, Rajeev, Leguizamo, Isai

[International Worm Meeting, 2021]

A high glycemic diet (i.e. high sugar diet) is among the main factors contributing to severe and detrimental human health issues such as type 2 diabetes, cardiovascular diseases, and metabolic abnormalities. Underlying mechanisms involved in gene expression regulation and metabolism as a result of a high sugar diet continue to remain poorly understood. In our study, we use the genetic model system Caenorhabditis elegans to further investigate the impact a glucose-supplemented diet has on gene expression changes/regulation. Previously, we showed that a glucose-supplemented diet increases lipid composition, sensitivity to stress responses, and significantly alters the transcriptome profile (RNA-sequencing studies). We observed differential gene expression chromosomal maps and identified various clusters majorly found in Chromosome IV/V. Given that a link exists between chromosomal clustering and transcriptional regulation we further sought to identify gene regulators. The transcriptomic analysis revealed 140 gene expression regulators among the 2,370 differentially regulated genes as a result of a glucose-supplemented diet. Furthermore, we identified the acs-2 gene is a glucose-responsive gene, as shown by RNA-sequencing analysis, the acs-2::GFP reporter strain, and quantitative RT-PCR. Here, we developed a targeted RNA interference (RNAi) screen to identify the transcriptional regulators that respond to a glucose diet and impact the expression of acs-2::GFP. From our screen, we identified 20 regulators that significantly impact the expression of acs-2 transcript in a glucose diet dependent manner; 18 regulators increase and 2 regulators decrease acs-2::GFP expression. We also identified 13 gene regulators that increase acs-2::GFP expression in standard RNAi diet. Several of the regulators identified also show homology to human gene regulators suggesting conserved gene expression regulators between C. elegans and Humans. Together, these studies add to our understanding of the transcriptional and molecular changes that occur in response to a glucose-supplemented diet.