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Abstract BackgroundThe vertebrate enteric nervous system (ENS) consists of a series of interconnected ganglia within the gastrointestinal (GI) tract, formed during development following migration of enteric neural crest cells (ENCCs) into the primitive gut tube. Much work has been done to unravel the complex nature of extrinsic and intrinsic factors that regulate processes that direct migration, proliferation, and differentiation of ENCCs. However, ENS development is a complex process, and we still have much to learn regarding the signaling factors that regulate ENCC development. ResultsHere in zebrafish, through transcriptomic, in situ transcript expression, immunohistochemical analysis, and chemical attenuation, we identified a time‐dependent role for bone morphogenetic protein (BMP) in the maintenance of Phox2bb+enteric progenitor numbers and/or time of differentiation of the progenitor pool. In support of our in silico transcriptomic analysis, we identified expression of a novel ENS ligand‐encoding transcript,bmp5, within developmental regions of ENCCs. Through generation of a novel mutantbmp5wmr2andbmp5crispants, we identified a functional role for BMP5 in proper GI tract colonization, wherebyphox2bb+enteric progenitor numbers were reduced. ConclusionAltogether, this work identified time‐dependent roles for BMP signaling and a novel extrinsic factor, BMP5, that is necessary for vertebrate ENS formation.
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Crk adaptor proteins are necessary for the development of the zebrafish retina
Abstract BackgroundThe development of the central nervous system (CNS) requires critical cell signaling molecules to coordinate cell proliferation and migration in order to structure the adult tissue. Chicken tumor virus #10 Regulator of Kinase (CRK) and CRK‐like (CRKL) are adaptor proteins with pre‐metazoan ancestry and are known to be required for patterning laminated structures downstream of Reelin (RELN), such as the cerebral cortex, cerebellum, and hippocampus. CRK and CRKL also play crucial roles in a variety of other growth factor and extracellular matrix signaling cascades. The neuronal retina is another highly laminated structure within the CNS that is dependent on migration for proper development, but the cell signaling mechanisms behind neuronal positioning in the retina are only partly understood. ResultsWe find thatcrkandcrklhave largely overlapping expression within the developing zebrafish nervous system. We find that their disruption results in smaller eye size and loss of retinal lamination. ConclusionsOur data indicate that Crk adaptors are critical for proper development of the zebrafish neural retina in acrk/crkldose‐dependent manner.
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- Award ID(s):
- 1656510
- PAR ID:
- 10362359
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Developmental Dynamics
- Volume:
- 251
- Issue:
- 2
- ISSN:
- 1058-8388
- Format(s):
- Medium: X Size: p. 362-376
- Size(s):
- p. 362-376
- Sponsoring Org:
- National Science Foundation
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