Mapping early fate determination in Lgr5+ crypt stem cells using a novel Ki67‐RFP allele. (4th August 2014)

• Record Type: Journal Article
• Authors: Basak, Onur; van de Born, Maaike; Korving, Jeroen; Beumer, Joep; van der Elst, Stefan; van Es, Johan H; Clevers, Hans
• Is Part Of: EMBO journal. Volume 33:Number 18(2014)
• Page Start: 2057
• Page End: 2068
• Publication Date: 2014-08-04
• Subjects: Molecular biology -- Periodicals; 572.805
• DOI: 10.15252/embj.201488017
• Languages: English
• ISSNs: 0261-4189

Abstract

<abstract abstract-type="main" id="embj201488017-abs-0001"> <title>Abstract</title> <p>Cycling Lgr5⁺ stem cells fuel the rapid turnover of the adult intestinal epithelium. The existence of quiescent Lgr5⁺ cells has been reported, while an alternative quiescent stem cell population is believed to reside at crypt position +4. Here, we generated a novel <italic>Ki67</italic>^{<italic>RFP</italic>} knock‐in allele that identifies dividing cells. Using <italic>Lgr5‐GFP;Ki67</italic>^{<italic>RFP</italic>} mice, we isolated crypt stem and progenitor cells with distinct Wnt signaling levels and cell cycle features and generated their molecular signature using microarrays. Stem cell potential of these populations was further characterized using the intestinal organoid culture. We found that Lgr5^high stem cells are continuously in cell cycle, while a fraction of Lgr5^low progenitors that reside predominantly at +4 position exit the cell cycle. Unlike fast dividing CBCs, Lgr5^low Ki67⁻ cells have lost their ability to initiate organoid cultures, are enriched in secretory differentiation factors, and resemble the Dll1 secretory precursors and the label‐retaining cells of Winton and colleagues. Our findings support the cycling stem cell hypothesis and highlight the cell cycle heterogeneity of early progenitors during lineage commitment.</p> </abstract>