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Unique homeobox codes delineate all the neuron classes of C. elegans.

ABSTRACT: It is not known at present whether neuronal cell-type diversity-defined by cell-type-specific anatomical, biophysical, functional and molecular signatures-can be reduced to relatively simple molecular descriptors of neuronal identity¹. Here we show, through examination of the expression of all of the conserved homeodomain proteins encoded by the Caenorhabditis elegans genome², that the complete set of 118 neuron classes of C. elegans can be described individually by unique combinations of the expression of homeodomain proteins, thereby providing-to our knowledge-the simplest currently known descriptor of neuronal diversity. Computational and genetic loss-of-function analyses corroborate the notion that homeodomain proteins not only provide unique descriptors of neuron type, but also have a critical role in specifying neuronal identity. We speculate that the pervasive use of homeobox genes in defining unique neuronal identities reflects the evolutionary history of neuronal cell-type specification.

SUBMITTER: Reilly MB

PROVIDER: S-EPMC7587405 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Unique homeobox codes delineate all the neuron classes of C. elegans.

Reilly Molly B MB Cros Cyril C Varol Erdem E Yemini Eviatar E Hobert Oliver O

Nature 20200819 7822

It is not known at present whether neuronal cell-type diversity-defined by cell-type-specific anatomical, biophysical, functional and molecular signatures-can be reduced to relatively simple molecular descriptors of neuronal identity<sup>1</sup>. Here we show, through examination of the expression of all of the conserved homeodomain proteins encoded by the Caenorhabditis elegans genome<sup>2</sup>, that the complete set of 118 neuron classes of C. elegans can be described individually by unique ...[more]

PMID: 32814896

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