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PCP and Wnt pathway components act in parallel during zebrafish mechanosensory hair cell orientation.

ABSTRACT: Planar cell polarity (PCP) plays crucial roles in developmental processes such as gastrulation, neural tube closure and hearing. Wnt pathway mutants are often classified as PCP mutants due to similarities between their phenotypes. Here, we show that in the zebrafish lateral line, disruptions of the PCP and Wnt pathways have differential effects on hair cell orientations. While mutations in the PCP genes vangl2 and scrib cause random orientations of hair cells, mutations in wnt11f1, gpc4 and fzd7a/b induce hair cells to adopt a concentric pattern. This concentric pattern is not caused by defects in PCP but is due to misaligned support cells. The molecular basis of the support cell defect is unknown but we demonstrate that the PCP and Wnt pathways work in parallel to establish proper hair cell orientation. Consequently, hair cell orientation defects are not solely explained by defects in PCP signaling, and some hair cell phenotypes warrant re-evaluation.

SUBMITTER: Navajas Acedo J

PROVIDER: S-EPMC6728366 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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PCP and Wnt pathway components act in parallel during zebrafish mechanosensory hair cell orientation.

Navajas Acedo Joaquin J Voas Matthew G MG Alexander Richard R Woolley Thomas T Unruh Jay R JR Li Hua H Moens Cecilia C Piotrowski Tatjana T

Nature communications 20190905 1

Planar cell polarity (PCP) plays crucial roles in developmental processes such as gastrulation, neural tube closure and hearing. Wnt pathway mutants are often classified as PCP mutants due to similarities between their phenotypes. Here, we show that in the zebrafish lateral line, disruptions of the PCP and Wnt pathways have differential effects on hair cell orientations. While mutations in the PCP genes vangl2 and scrib cause random orientations of hair cells, mutations in wnt11f1, gpc4 and fzd7 ...[more]

PMID: 31488837

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PCP and Wnt pathway components act in parallel during zebrafish mechanosensory hair cell orientation.

Publications

PCP and Wnt pathway components act in parallel during zebrafish mechanosensory hair cell orientation.

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