Overexpression of DYRK1A, a Down Syndrome Candidate gene, Impairs Primordial Germ Cells Maintenance and Migration in zebrafish

Yanyan Liu,He Wang,Huaqin Sun,Mingfeng Liu,Ziyuan Lin

doi:10.1038/s41598-017-15730-w

Yanyan Liu, He Wang + Show 3 more

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https://doi.org/10.1038/s41598-017-15730-w

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Journal: Scientific Reports	Publication Date: Nov 10, 2017
Citations: 10	License type: open-access

Affiliation: Sichuan University, University of Hong Kong

Abstract

DYRK1A, located on chromosome 21, is a major candidate gene of Down syndrome (DS, trisomy21), and its overexpression is associated with abnormal phenotype of Down syndrome patients. The defects of gonads and germ cells in Down Syndrome suggest that overexpression of DYRK1A has potential effect on primordial germ cells (PGCs) development. Human and zebrafish DYRK1A protein sequence possess 75.6% similarity and same function domains, suggesting the evolutional conservation. Here, we used zebrafish model to detect the definite role of excessive expression of DYRK1A in PGCs development during embryogenesis. We injected DYRK1A mRNA into embryos and detected the PGCs marker gene vasa and nanos1. Results showed depletion in numbers and disordering migration of PGCs in human or zebrafish DYRK1A overexpressed zebrafish embryos. Quantitative proteome analysis indicated that embryonic proteins were significantly altered in DYRK1A overexpressed embryos. Of note, ca15b and piwil1, two identified critical factors for PGCs development, showed ectopic expression induced by overexpressed DYRK1A. In brief, we demonstrate that overexpression of DYRK1A, a candidate gene of Down’s syndrome, impairs PGCs development during early embryogenesis by altering key factors in embryos. Importantly, our work may provide a conceivable mechanism for the gonads and germ cells defects of Down syndrome patients.

Highlights

DYRK1A gene in human maps to the Down syndrome critical region q22.2 of chromosome 218–12
Expression of DYRK1A mRNA during zebrafish embryogenesis was examined by whole mount in situ hybridization (WISH), and two nonoverlapping probes for DYRK1A, localizing at positions 440–1189 bp and 1701–2419 bp (Fig. 2a), were used to demonstrate specificity and obtain identical spatially restricted expression patterns[26]
Expression of DYRK1A protein during zebrafish embryogenesis was examined by using whole-mount immunohistochemistry (WIHC)

Summary

Introduction

DYRK1A gene in human maps to the Down syndrome critical region q22.2 of chromosome 218–12. Zebrafish PGCs are segregated from the somatic lineage, and start a characteristic performance of migration toward the genital ridges shortly thereafter[20,21]. This migration process is completed within the first developmental day, and can be detected at high resolution using simple microscopy, due to the optical transparency of zebrafish embryos. Following their specification during early embryonic stages, PGCs polarize and acquire motility As they migrate, PGCs are presented with attractive and repulsive guidance cues provided by somatic cells along the migration path[23], which exist complicated developmental and cellular mechanisms. Some key factors play critical role for this migration process, such as Piwil[1] and Ca15b23–25

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