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Non-neural surface ectodermal rosette formation and F-actin dynamics drive mammalian neural tube closure.

ABSTRACT: The mechanisms underlying mammalian neural tube closure remain poorly understood. We report a unique cellular process involving multicellular rosette formation, convergent cellular protrusions, and F-actin cable network of the non-neural surface ectodermal cells encircling the closure site of the posterior neuropore, which are demonstrated by scanning electron microscopy and genetic fate mapping analyses during mouse spinal neurulation. These unique cellular structures are severely disrupted in the surface ectodermal transcription factor Grhl3 mutants that exhibit fully penetrant spina bifida. We propose a novel model of mammalian neural tube closure driven by surface ectodermal dynamics, which is computationally visualized.

SUBMITTER: Zhou CJ

PROVIDER: S-EPMC7210071 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Non-neural surface ectodermal rosette formation and F-actin dynamics drive mammalian neural tube closure.

Zhou Chengji J CJ Ji Yu Y Reynolds Kurt K McMahon Moira M Garland Michael A MA Zhang Shuwen S Sun Bo B Gu Ran R Islam Mohammad M Liu Yue Y Zhao Tianyu T Hsu Grace G Iwasa Janet J

Biochemical and biophysical research communications 20200402 3

The mechanisms underlying mammalian neural tube closure remain poorly understood. We report a unique cellular process involving multicellular rosette formation, convergent cellular protrusions, and F-actin cable network of the non-neural surface ectodermal cells encircling the closure site of the posterior neuropore, which are demonstrated by scanning electron microscopy and genetic fate mapping analyses during mouse spinal neurulation. These unique cellular structures are severely disrupted in ...[more]

PMID: 32248972

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