Origin of the zebrafish endocrine and exocrine pancreas

Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois 60615, USA.
Developmental Dynamics (Impact Factor: 2.38). 06/2007; 236(6):1558-69. DOI: 10.1002/dvdy.21168
Source: PubMed


Here, we report a detailed fate map of the zebrafish pancreas at the early gastrula stage of development (6 hours postfertilization; hpf). We show that, at this stage, both pancreas and liver progenitors are symmetrically localized in two broad domains relative to the dorsal organizer. We demonstrate that the dorsal and ventral pancreatic buds can derive from common progenitor pools at 6 hpf, but often derive from independent populations. Endocrine vs. exocrine pancreas show a similar pattern of progenitors, consistent with descriptions of the dorsal bud being strictly endocrine and the ventral bud primarily exocrine. In general, we find that endocrine/dorsal bud progenitors are located more dorsally than the exocrine pancreas/ventral bud progenitors. Later in gastrulation (10 hpf), pancreas progenitors have migrated to bilateral domains at the equator of the embryo. Our fate map will assist with design and interpretation of future experiments to understand early pancreas development.

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    • "The fish pancreas does not often prove to be a ready source of tissue for electron microscopic study. The main fish pancreas is both anatomically [5] and developmentally [6] similar to the mammalian pancreas, whereas major differences are apparent in other fish species. In adult zebrafish, the main pancreas contains several principal islets surrounded by exocrine tissue. "
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    01/2015; 2015:1-6. DOI:10.1155/2015/686571
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    • "Expression of Pdx1 is very dynamic in the developing pancreas and genetic analyses using conditional and hypomorphic Pdx1 mutant alleles in mouse have already indicated that Pdx1 is important in various specification and differentiation events [38-41]. In zebrafish, fate-mapping studies indicated that a spatial separation of the future pancreatic DB versus VB progenitors is already established shortly after gastrulation (10 hpf) [42,43]. Medium levels of pdx1 expression during early somitogenesis (10 to 15 hpf) correlate with VB fate specification [44]. "
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    BMC Biology 10/2011; 9(1):75. DOI:10.1186/1741-7007-9-75 · 7.98 Impact Factor
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    • "Understanding the mechanisms that regulate pancreatic development has been facilitated by studies in model organisms, including zebrafish (Danio rerio). The exocrine component of the zebrafish pancreas arises from endodermal progenitor cells that migrate from the gut tube, requiring the transcriptional activities of pancreatic and duodenal homeobox (Pdx1) and pancreas-specific transcription factor (Ptf1a) (Yee et al., 2001; Biemar et al., 2001; Lin et al., 2004; Zecchin et al., 2004; Yee et al., 2005; Ward et al., 2007). Signaling pathways, including wingless-type mouse mammary tumor virus integration site family members (Wnt), fibroblast growth factor (Fgf) and sonic hedgehog (Shh), are implicated in the induction and patterning of exocrine pancreatic tissues (Goessling et al., 2008; Manfroid et al., 2007; Dong et al., 2007; Chung and Stainier, 2008). "
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