PT  - JOURNAL ARTICLE
AU  - Mizuki Kurashina
AU  - Jane Wang
AU  - Kathy Kyungeun Lee
AU  - Arpun Johal
AU  - Kota Mizumoto
TI  - Sustained expression of <em>unc-4/Hox</em> and <em>unc-37/Groucho</em> in postmitotic neurons specifies the spatial organization of the cholinergic synapses in <em>C. elegans</em>
AID  - 10.1101/2020.12.22.423995
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.12.22.423995
4099  - http://biorxiv.org/content/early/2020/12/22/2020.12.22.423995.short
4100  - http://biorxiv.org/content/early/2020/12/22/2020.12.22.423995.full
AB  - Neuronal cell fate determinants establish the identities of neurons by controlling gene expression to regulate neuronal morphology and synaptic connectivity. However, it is not understood if neuronal cell fate determinants have postmitotic functions in synapse pattern formation. Here we identify a novel role for UNC-4 homeobox protein and its corepressor UNC-37/Groucho, in tiled synaptic patterning of the cholinergic motor neurons in Caenorhabditis elegans. We show that unc-4 is not required during neurogenesis but is required in the postmitotic neurons for proper synapse patterning. In contrast, unc-37 is required in both developing and postmitotic neurons. The synaptic tiling defects of unc-4 mutants are suppressed by bar-1/β-catenin mutation, which positively regulates the expression of ceh-12/Hb9. Ectopic ceh-12 expression partly underlies the synaptic tiling defects of unc-4 and unc-37 mutants. Our results reveal a novel postmitotic role of neuronal cell fate determinants in synapse pattern formation through inhibiting the canonical Wnt signaling pathway.Competing Interest StatementThe authors have declared no competing interest.