Presentation Type
Poster
Discipline Track
Other
Molecular Biology
Abstract Type
Research/Clinical
Abstract
Homeoproteins are transcription factors that bind to DNA through a highly conserved binding domain known as the homeodomain (HD), which recognizes short regions rich in A-T. This DNA binding triggers the modulation of multiple target genes responsible for identity in various structures along the A-P axis of D. melanogaster. However, the high similarity of homeodomains and their affinity for widely distributed sites in the genome poses the "Hox paradox," which seeks to explain how homeoproteins acquire functional specificity so precisely. Previous evidence shows that homeoproteins like Antennapedia (Antp) form dimers with cofactors and other transcription factors to modulate their activity and also can form trimeric complexes with TBP/TFIIEβ/Exd.
For this reason, we have conducted transactivation analyses to determine the effect of Antp-TBP-TFIIEβ and Antp-TBP-Exd complexes on Antp's transcriptional activity. The experimental strategy involved transfecting HEK-293 cells with different combinations of plasmids producing Antp, TBP, TFIIEβ, and Exd, along with two reporter plasmids: a luciferase reporter with 5 binding sites for Antp and the sequence of a D. melanogaster basal promoter, and a β-galactosidase reporter. Our results reveal that the trimeric interaction of Antp-TBP-TFIIEβ induces a highly significant increase of 173% in Antp transcriptional activity. On the other hand, Antp-TBP-Exd trimer shows opposite results by decreasing Antp transcriptional activity until 61%. These findings suggest that the trimeric complexes Antp-TBP/TFIIEβ/Exd play a role in modulating Antp's transcriptional activity, raising new questions about the in vivo effects of these complexes on Antp interactome and target genes.
Academic/Professional Position
Graduate Student
Recommended Citation
Hernández-Bautista, Norma C.; Altamirano-Torres, Claudia A.; Montalvo Mendez, Ruben; Jiménez-Mejía, Gustavo; and Reséndez-Pérez, Diana, "Trimeric Antp-TBP complexes with TFIIEβ and Exd modulated the transcriptional activity of Antp" (2024). Research Symposium. 66.
https://scholarworks.utrgv.edu/somrs/2024/posters/66
Included in
Trimeric Antp-TBP complexes with TFIIEβ and Exd modulated the transcriptional activity of Antp
Homeoproteins are transcription factors that bind to DNA through a highly conserved binding domain known as the homeodomain (HD), which recognizes short regions rich in A-T. This DNA binding triggers the modulation of multiple target genes responsible for identity in various structures along the A-P axis of D. melanogaster. However, the high similarity of homeodomains and their affinity for widely distributed sites in the genome poses the "Hox paradox," which seeks to explain how homeoproteins acquire functional specificity so precisely. Previous evidence shows that homeoproteins like Antennapedia (Antp) form dimers with cofactors and other transcription factors to modulate their activity and also can form trimeric complexes with TBP/TFIIEβ/Exd.
For this reason, we have conducted transactivation analyses to determine the effect of Antp-TBP-TFIIEβ and Antp-TBP-Exd complexes on Antp's transcriptional activity. The experimental strategy involved transfecting HEK-293 cells with different combinations of plasmids producing Antp, TBP, TFIIEβ, and Exd, along with two reporter plasmids: a luciferase reporter with 5 binding sites for Antp and the sequence of a D. melanogaster basal promoter, and a β-galactosidase reporter. Our results reveal that the trimeric interaction of Antp-TBP-TFIIEβ induces a highly significant increase of 173% in Antp transcriptional activity. On the other hand, Antp-TBP-Exd trimer shows opposite results by decreasing Antp transcriptional activity until 61%. These findings suggest that the trimeric complexes Antp-TBP/TFIIEβ/Exd play a role in modulating Antp's transcriptional activity, raising new questions about the in vivo effects of these complexes on Antp interactome and target genes.