Identifying Notch-Regulated Gene and Biological Pathways Using a Specific Notch Signaling Inhibitor IMR-1A
Faculty Mentor
Dr. Jason Ashley
Presentation Type
Oral Presentation
Start Date
5-7-2025 11:10 AM
End Date
5-7-2025 11:30 AM
Location
PUB 317
Primary Discipline of Presentation
Biology
Abstract
Bone remodeling is a dynamic process requiring a balance between bone resorption by osteoclasts and bone formation by osteoblasts to maintain skeletal integrity. Disruptions to this equilibrium can lead to conditions such as osteoporosis. Osteoclasts originate from macrophages, and their differentiation is regulated. One key regulatory pathway is the Notch signaling pathway. Gamma-secretase, an enzyme involved in the initiation of notch signaling and multiple cellular functions, regulates Notch signaling and can be inhibited by DAPT.
Previous RNA-Seq analyses have been conducted to reveal Notch target genes by inhibiting gamma secretase using DAPT. However, distinguishing genes specifically regulated by the Notch pathway is challenging due to gamma-secretase's involvement in many non-Notch-related cellular functions.
To address this, we use IMR-1A, an inhibitor that disrupts the recruitment of Mastermind-like 1 (MAML1), a protein essential for forming the Notch transcriptional activation complex. This selective inhibition prevents the expression of Notch-specific target genes required for downstream Notch signaling effects. We perform functional enrichment analysis to classify DEGs into metabolic pathways, then representative genes from each pathway are selected for RT-qPCR validation following osteoclast differentiation under IMR-1A treatment. This validation will identify Notch-dependent DEGs and reveal pathways regulated by Notch signaling.
This study aims to isolate Notch-dependent DEGs and clarify the cellular processes potentially regulated by Notch signaling. Identifying key Notch-regulated genes may reveal potential therapeutic targets for mitigating osteoporosis symptoms and inhibiting osteoclast formation.
Recommended Citation
Astudillo, L., Da Silva, T. G., Wang, Z., Han, X., Jin, K., VanWye, J., ... & Capobianco, A. J. (2016). The small molecule IMR-1 inhibits the notch transcriptional activation complex to suppress tumorigenesis. Cancer research, 76(12), 3593-3603. Yu J, Canalis E. Notch and the regulation of osteoclast differentiation and function. Bone. 2020 Sep;138:115474. doi: 10.1016/j.bone.2020.115474. Epub 2020 Jun 8. PMID: 32526405; PMCID: PMC7423683.
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Identifying Notch-Regulated Gene and Biological Pathways Using a Specific Notch Signaling Inhibitor IMR-1A
PUB 317
Bone remodeling is a dynamic process requiring a balance between bone resorption by osteoclasts and bone formation by osteoblasts to maintain skeletal integrity. Disruptions to this equilibrium can lead to conditions such as osteoporosis. Osteoclasts originate from macrophages, and their differentiation is regulated. One key regulatory pathway is the Notch signaling pathway. Gamma-secretase, an enzyme involved in the initiation of notch signaling and multiple cellular functions, regulates Notch signaling and can be inhibited by DAPT.
Previous RNA-Seq analyses have been conducted to reveal Notch target genes by inhibiting gamma secretase using DAPT. However, distinguishing genes specifically regulated by the Notch pathway is challenging due to gamma-secretase's involvement in many non-Notch-related cellular functions.
To address this, we use IMR-1A, an inhibitor that disrupts the recruitment of Mastermind-like 1 (MAML1), a protein essential for forming the Notch transcriptional activation complex. This selective inhibition prevents the expression of Notch-specific target genes required for downstream Notch signaling effects. We perform functional enrichment analysis to classify DEGs into metabolic pathways, then representative genes from each pathway are selected for RT-qPCR validation following osteoclast differentiation under IMR-1A treatment. This validation will identify Notch-dependent DEGs and reveal pathways regulated by Notch signaling.
This study aims to isolate Notch-dependent DEGs and clarify the cellular processes potentially regulated by Notch signaling. Identifying key Notch-regulated genes may reveal potential therapeutic targets for mitigating osteoporosis symptoms and inhibiting osteoclast formation.
