Pineal progenitors originate from a non-neural territory limited by FGF signalling

TY - JOUR

T1 - Pineal progenitors originate from a non-neural territory limited by FGF signalling

AU - Staudt, Nicole

AU - Giger, Florence Antoinette Chantal

AU - Fielding, Triona

AU - Hutt, James Alan

AU - Foucher, Isabelle Brigette Anne

AU - Snowden, Victoria

AU - Hellich, Agathe

AU - Kiecker, Clemens Martin

AU - Houart, Corinne

PY - 2019/11/21

Y1 - 2019/11/21

N2 - The embryonic development of the pineal organ, a neuroendocrine gland on top of the diencephalon, remains enigmatic. Classic fate mapping studies suggested that pineal progenitors originate from the lateral border of the anterior neural plate. We show here, using gene expression and fate mapping/lineage tracing in zebrafish, that pineal progenitors originate, at least in part, from the non-neural ectoderm. Gene expression in chick indicates that this non-neural origin of pineal progenitors is conserved in amniotes. Genetic repression of placodal, but not neural crest, cell fate results in pineal hypoplasia in zebrafish, while mis-expression of transcription factors known to specify placodal identity during gastrulation promotes the formation of ectopic pineal progenitors. We also demonstrate that Fibroblast Growth Factors (FGFs) position the pineal progenitor domain within the non-neural border by repressing pineal fate and that the Otx transcription factors promote pinealogenesis by inhibiting this FGF activity. The non-neural origin of the pineal organ reveals an underlying similarity in the formation of the pineal and pituitary glands and suggests that all CNS neuroendocrine organs may require a non-neural contribution to form neurosecretory cells.

AB - The embryonic development of the pineal organ, a neuroendocrine gland on top of the diencephalon, remains enigmatic. Classic fate mapping studies suggested that pineal progenitors originate from the lateral border of the anterior neural plate. We show here, using gene expression and fate mapping/lineage tracing in zebrafish, that pineal progenitors originate, at least in part, from the non-neural ectoderm. Gene expression in chick indicates that this non-neural origin of pineal progenitors is conserved in amniotes. Genetic repression of placodal, but not neural crest, cell fate results in pineal hypoplasia in zebrafish, while mis-expression of transcription factors known to specify placodal identity during gastrulation promotes the formation of ectopic pineal progenitors. We also demonstrate that Fibroblast Growth Factors (FGFs) position the pineal progenitor domain within the non-neural border by repressing pineal fate and that the Otx transcription factors promote pinealogenesis by inhibiting this FGF activity. The non-neural origin of the pineal organ reveals an underlying similarity in the formation of the pineal and pituitary glands and suggests that all CNS neuroendocrine organs may require a non-neural contribution to form neurosecretory cells.

KW - Circumventricular organs

KW - Neurulation

KW - Neural plate border

KW - Otx

KW - FGF

KW - Placode

KW - Pineal

KW - ENDOCRINE

KW - ZEBRAFISH

KW - CHICK

UR - http://www.scopus.com/inward/record.url?scp=85075493525&partnerID=8YFLogxK

U2 - 10.1242/dev.171405

DO - 10.1242/dev.171405

M3 - Article

SN - 0950-1991

VL - 146

JO - Development

JF - Development

IS - 22

M1 - dev171405

ER -