TY  - JOUR
AU  - Monastirioti, Maria
AU  - Koltsaki, Ioanna
AU  - Pitsidianaki, Ioanna
AU  - Skafida, Emilia
AU  - Batsiotos, Nikolaos
AU  - Delidakis, Christos
TI  - Notch-Dependent Expression of the Drosophila Hey Gene Is Supported by a Pair of Enhancers with Overlapping Activities.
JO  - Genes
VL  - 15
IS  - 8
SN  - 2073-4425
CY  - Basel
PB  - MDPI
M1  - DKFZ-2024-01768
SP  - 1071
PY  - 2024
AB  - Drosophila Hey is a basic helix-loop-helix-orange (bHLH-O) protein with an important role in the establishment of distinct identities of postmitotic cells. We have previously identified Hey as a transcriptional target and effector of Notch signalling during the asymmetric division of neuronal progenitors, generating neurons of two types, and we have shown that Notch-dependent expression of Hey also marks a subpopulation of the newborn enteroendocrine (EE) cells in the midgut primordium of the embryo. Here, we investigate the transcriptional regulation of Hey in neuronal and intestinal tissues. We isolated two genomic regions upstream of the promoter (HeyUP) and in the second intron (HeyIN2) of the Hey gene, based on the presence of binding motifs for Su(H), the transcription factor that mediates Notch activity. We found that both regions can direct the overlapping expression patterns of reporter transgenes recapitulating endogenous Hey expression. Moreover, we showed that while HeyIN2 represents a Notch-dependent enhancer, HeyUP confers both Notch-dependent and independent transcriptional regulation. We induced mutations that removed the Su(H) binding motifs in either region and then studied the enhancer functionality in the respective Hey mutant lines. Our results provide direct evidence that although both enhancers support Notch-dependent regulation of the Hey gene, their role is redundant, as a Hey loss-of-function lethal phenotype is observed only after deletion of all their Su(H) binding motifs by CRISPR/Cas9.
KW  - Animals
KW  - Drosophila Proteins: genetics
KW  - Drosophila Proteins: metabolism
KW  - Basic Helix-Loop-Helix Transcription Factors: genetics
KW  - Basic Helix-Loop-Helix Transcription Factors: metabolism
KW  - Receptors, Notch: genetics
KW  - Receptors, Notch: metabolism
KW  - Gene Expression Regulation, Developmental
KW  - Enhancer Elements, Genetic
KW  - Drosophila melanogaster: genetics
KW  - Repressor Proteins: genetics
KW  - Repressor Proteins: metabolism
KW  - Promoter Regions, Genetic
KW  - Signal Transduction: genetics
KW  - Drosophila (Other)
KW  - Hey (Other)
KW  - Notch (Other)
KW  - Su(H) binding site (Other)
KW  - basic helix–loop–helix–orange (Other)
KW  - central nervous system (Other)
KW  - enhancer (Other)
KW  - midgut (Other)
KW  - Drosophila Proteins (NLM Chemicals)
KW  - Basic Helix-Loop-Helix Transcription Factors (NLM Chemicals)
KW  - Receptors, Notch (NLM Chemicals)
KW  - N protein, Drosophila (NLM Chemicals)
KW  - Repressor Proteins (NLM Chemicals)
KW  - Su(H) protein, Drosophila (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:39202431
C2  - pmc:PMC11353301
DO  - DOI:10.3390/genes15081071
UR  - https://inrepo02.dkfz.de/record/292522
ER  -