Sci Adv.: auth. group Benton, co-auth.: T.Auer and GTF

Sci Adv. 2021 Aug 6;7(32):eabe3745. doi: 10.1126/sciadv.abe3745. Print 2021 Aug.

Olfactory receptor-dependent receptor repression in Drosophila

Kaan Mika 1Steeve Cruchet 1Phing Chian Chai 1Lucia L Prieto-Godino 1Thomas O Auer 1Sylvain Pradervand 1 2 3Richard Benton 4

Free article

Abstract

In olfactory systems across phyla, most sensory neurons express a single olfactory receptor gene selected from a large genomic repertoire. We describe previously unknown receptor gene-dependent mechanisms that ensure singular expression of receptors encoded by a tandem gene array [Ionotropic receptor 75c (Ir75c), Ir75b, and Ir75a, organized 5′ to 3′] in Drosophila melanogaster Transcription from upstream genes in the cluster runs through the coding region of downstream loci and inhibits their expression in cis, most likely via transcriptional interference. Moreover, Ir75c blocks accumulation of other receptor proteins in trans through a protein-dependent, posttranscriptional mechanism. These repression mechanisms operate in endogenous neurons, in conjunction with cell type-specific gene regulatory networks, to ensure unique receptor expression. Our data provide evidence for inter-olfactory receptor regulation in invertebrates and highlight unprecedented, but potentially widespread, mechanisms for ensuring exclusive expression of chemosensory receptors, and other protein families, encoded by tandemly arranged genes.