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bioRxiv · 10.1101/2021.09.29.462302

Repression of the Hox gene abd-A by ELAV-mediated Transcriptional Interference

Castro Alvarez, J. J.·Revel, M.·Cleard, F.·Pauli, D.·Karch, F.·Maeda, R. K.
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Abstract

Intergenic transcription is a common feature of eukaryotic genomes and performs important and diverse cellular functions. Here, we investigate the iab-8 ncRNA from the Drosophila Bithorax Complex and show that this RNA is able to repress the transcription of genes located at its 3 end by a sequence-independent, transcriptional interference mechanism. Although this RNA is expressed in the early epidermis and CNS, we find that its repressive activity is limited to the CNS, where in wild-type embryos, it acts on the Hox gene, abd-A located immediately downstream of it. The CNS specificity is achieved through a 3 extension of the transcript, mediated by the neuronal-specific, RNA-binding protein, ELAV. Loss of ELAV activity eliminates the 3 extension and results in the ectopic activation of abd-A. Thus, a tissue-specific change in the length of a ncRNA is used to generate a precise pattern of gene expression in a higher eukaryote.

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Castro Alvarez, J. J., Revel, M., Cleard, F., Pauli, D., Karch, F., Maeda, R. K.. 2021-09-30. Repression of the Hox gene abd-A by ELAV-mediated Transcriptional Interference. https://doi.org/10.1101/2021.09.29.462302

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