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- Kim, Anna A., et al.
(författare)
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Independently paced Ca2+ oscillations in progenitor and differentiated cells in an ex vivo epithelial organ
- 2022
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Ingår i: Journal of Cell Science. - : The Company of Biologists. - 0021-9533 .- 1477-9137. ; 135:14
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Tidskriftsartikel (refereegranskat)abstract
- Cytosolic Ca2+ is a highly dynamic, tightly regulated and broadly conserved cellular signal. Ca2+ dynamics have been studied widely in cellular monocultures, yet organs in vivo comprise heterogeneous populations of stem and differentiated cells. Here, we examine Ca2+ dynamics in the adult Drosophila intestine, a self-renewing epithelial organ in which stem cells continuously produce daughters that differentiate into either enteroendocrine cells or enterocytes. Live imaging of whole organs ex vivo reveals that stem-cell daughters adopt strikingly distinct patterns of Ca2+ oscillations after differentiation: enteroendocrine cells exhibit single-cell Ca2+ oscillations, whereas enterocytes exhibit rhythmic, long-range Ca2+ waves. These multicellular waves do not propagate through immature progenitors (stem cells and enteroblasts), of which the oscillation frequency is approximately half that of enteroendocrine cells. Organ-scale inhibition of gap junctions eliminates Ca2+ oscillations in all cell types – even, intriguingly, in progenitor and enteroendocrine cells that are surrounded only by enterocytes. Our findings establish that cells adopt fate-specific modes of Ca2+ dynamics as they terminally differentiate and reveal that the oscillatory dynamics of different cell types in a single, coherent epithelium are paced independently.
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| 2. |
- Kim, Anna A, et al.
(författare)
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Regional Calcium Dynamics in Drosophila Adult Midgut
- 2019
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Ingår i: Mol. Biol. Cell.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Although calcium dynamics are widely studied in cell culture, little has been reported on the topic for adult organs. We find striking regional and cell-type specific differences in calcium dynamics in the three major cell types of the adult Drosophila intestine. The adult fruit fly intestine is a compelling platform for studying intercellular dynamics and interactions. This stem cell-based epithelium is a reductionist model system of the mammalian small bowel with conserved features. The multi-cellular epithelium consists of three major cell types: progenitor cells that give rise to new cells (including stem cells), enteroendocrine cells that are hormone signaling cells, and enterocytes that are large absorptive cells.We find regional and cell-type specific variations in calcium signaling dynamics within this functionally compartmentalized organ, using confocal imaging of ex vivo cultured fly intestines. Progenitor and enteroendocrine cells indicate oscillatory intracellular calcium dynamics of slower and faster frequencies respectively, and enterocytes demonstrate the presence of traveling calcium waves. Our findings may establish a novel model for studying spatio-temporal organization of cellular to organ-level calcium dynamics in a renewable adult organ.
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