Elucidating Gli3 and Hand2 interactions in the developing mandible
In: Student Reports, Summer 2023, The Jackson Laboratory
Steve Murray, Ph.D.
Gli3 and Hand2 have previously been shown to engage in a synergistic relationship during craniofacial development; specifically, they are required for proper patterning of the mandible. However, it is not clear how the genomic context influences Gli3 and Hand2 interactions. We applied genomic and transcriptomic approaches to further understand the molecular basis governing Gli3 and Hand2 activity in the mandible using epitope tagged mouse models. Phenotype enrichment analysis in shared and unique Gli3-Hand2 ChIP-seq peak datasets suggested that Gli3 and Hand2 interact with each other during craniofacial development. Further, bioinformatic analysis of RNA-seq data highlighted genes bound by Gli3 and Hand2 are linked to severe craniofacial abnormalities and identified top differentially expressed genes in Gli2/Gli3 and Hand2 conditional knockouts. Motif enrichment allowed us to confirm most frequently occurring E-box variants and Gli binding sites within bound regions. To determine if Hand2 and Gli3 directly interact in vivo, we applied Proximity Ligation Assay; however, there were numerous unspecified signals that prevented us from distinguishing between background and real signals. As future directions, further optimization of the protocol and additional quantification using imaging software may help to resolve this technical issue.
Hossain, Aria, "Elucidating Gli3 and Hand2 interactions in the developing mandible" (2023). Summer and Academic Year Student Reports. 2752.