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The Drosophila actin nucleator DAAM is essential for left-right asymmetry.

ABSTRACT: Left-Right (LR) asymmetry is essential for organ positioning, shape and function. Myosin 1D (Myo1D) has emerged as an evolutionary conserved chirality determinant in both Drosophila and vertebrates. However, the molecular interplay between Myo1D and the actin cytoskeleton underlying symmetry breaking remains poorly understood. To address this question, we performed a dual genetic screen to identify new cytoskeletal factors involved in LR asymmetry. We identified the conserved actin nucleator DAAM as an essential factor required for both dextral and sinistral development. In the absence of DAAM, organs lose their LR asymmetry, while its overexpression enhances Myo1D-induced de novo LR asymmetry. These results show that DAAM is a limiting, LR-specific actin nucleator connecting up Myo1D with a dedicated F-actin network important for symmetry breaking.

SUBMITTER: Chougule A

PROVIDER: S-EPMC7200016 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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The Drosophila actin nucleator DAAM is essential for left-right asymmetry.

Chougule Anil A Lapraz François F Földi István I Cerezo Delphine D Mihály József J Noselli Stéphane S

PLoS genetics 20200423 4

Left-Right (LR) asymmetry is essential for organ positioning, shape and function. Myosin 1D (Myo1D) has emerged as an evolutionary conserved chirality determinant in both Drosophila and vertebrates. However, the molecular interplay between Myo1D and the actin cytoskeleton underlying symmetry breaking remains poorly understood. To address this question, we performed a dual genetic screen to identify new cytoskeletal factors involved in LR asymmetry. We identified the conserved actin nucleator DAA ...[more]

PMID: 32324733

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