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A low affinity cis-regulatory BMP response element restricts target gene activation to subsets of Drosophila neurons.

ABSTRACT: Retrograde BMP signaling and canonical pMad/Medea-mediated transcription regulate diverse target genes across subsets of Drosophila efferent neurons, to differentiate neuropeptidergic neurons and promote motor neuron terminal maturation. How a common BMP signal regulates diverse target genes across many neuronal subsets remains largely unresolved, although available evidence implicates subset-specific transcription factor codes rather than differences in BMP signaling. Here we examine the cis-regulatory mechanisms restricting BMP-induced FMRFa neuropeptide expression to Tv4-neurons. We find that pMad/Medea bind at an atypical, low affinity motif in the FMRFa enhancer. Converting this motif to high affinity caused ectopic enhancer activity and eliminated Tv4-neuron expression. In silico searches identified additional motif instances functional in other efferent neurons, implicating broader functions for this motif in BMP-dependent enhancer activity. Thus, differential interpretation of a common BMP signal, conferred by low affinity pMad/Medea binding motifs, can contribute to the specification of BMP target genes in efferent neuron subsets.

SUBMITTER: Berndt AJ

PROVIDER: S-EPMC7669266 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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A low affinity <i>cis</i>-regulatory BMP response element restricts target gene activation to subsets of Drosophila neurons.

Berndt Anthony Je AJ Othonos Katerina M KM Lian Tianshun T Flibotte Stephane S Miao Mo M Bhuiyan Shamsuddin A SA Cho Raymond Y RY Fong Justin S JS Hur Seo Am SA Pavlidis Paul P Allan Douglas W DW

eLife 20201030

Retrograde BMP signaling and canonical pMad/Medea-mediated transcription regulate diverse target genes across subsets of <i>Drosophila</i> efferent neurons, to differentiate neuropeptidergic neurons and promote motor neuron terminal maturation. How a common BMP signal regulates diverse target genes across many neuronal subsets remains largely unresolved, although available evidence implicates subset-specific transcription factor codes rather than differences in BMP signaling. Here we examine the ...[more]

PMID: 33124981

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A low affinity cis-regulatory BMP response element restricts target gene activation to subsets of Drosophila neurons.

Publications

A low affinity <i>cis</i>-regulatory BMP response element restricts target gene activation to subsets of Drosophila neurons.

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