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bioRxiv · 10.1101/2020.06.04.134767

The conserved ASCL1/MASH-1 ortholog HLH-3 specifies sex-specific ventral cord motor neuron fate in C. elegans

Perez, L. M.·Alfonso, A.
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Abstract

Neural specification can be regulated by one or many transcription factors. Here we identify a novel role for one conserved proneural factor, the bHLH protein HLH-3, implicated in the specification of sex-specific ventral cord motor neurons in C. elegans. In the process of characterizing the role of hlh-3 in neural specification, we document that differentiation of the ventral cord type C neurons, VCs, within their motor neuron class, is dynamic in time and space. Expression of VC class-specific and subclass-specific identity genes is distinct through development and dependent on where they are along the A-P axis (and their position in proximity to the vulva). Our characterization of the expression of VC class and VC subclass-specific differentiation markers in the absence of hlh-3 function reveals that VC fate specification, differentiation, and morphology requires hlh-3 function. Finally, we conclude that hlh-3 cell-autonomously specifies VC cell fate.

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Perez, L. M., Alfonso, A.. 2020-06-05. The conserved ASCL1/MASH-1 ortholog HLH-3 specifies sex-specific ventral cord motor neuron fate in C. elegans. https://doi.org/10.1101/2020.06.04.134767

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