Localization of Indian hedgehog and PTH/PTHrP receptor in relation to chondrocyte proliferation during mouse bone development. Dev Growth Differ

Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
Development Growth and Regeneration (Impact Factor: 2.42). 03/2005; 47(2):59-63. DOI: 10.1111/j.1440-169x.2004.00781.x
Source: PubMed


We have developed a useful approach to examine the pattern of gene expression in comparison to cell proliferation, using double in situ hybridization and immunofluorescence. Using this system, we examined the expression of Indian hedgehog (Ihh) and PTH/PTHrP receptor (PPR) mRNA in relation to chondrocyte proliferation during embryonic mouse bone development. Both genes are expressed strongly in prehypertrophic and early hypertrophic chondrocytes, and there is a strong correlation between upregulation of both Ihh and PPR expression and chondrocyte cell cycle arrest. At embryonic day (E14.5), PPR mRNA upregulation begins in the columnar chondrocytes just prior to cell cycle exit, but at later time points expression is only observed in the postproliferative region. In contrast, Ihh mRNA expression overlaps slightly with the region of columnar proliferating chondrocytes at all stages. This study provides further evidence that in the developing growth plate, cell cycle exit and upregulation of Ihh and PPR mRNA expression are coupled.

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Available from: Helen Maclean, Oct 25, 2015
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    • "The transition from proliferating into hypertrophic chondrocytes is demarcated by the onset of Ihh expression. The distance from the joint to the distal limit of the Ihh expression domain therefore defines the region of proliferating chondrocytes (MacLean and Kronenberg, 2005). We found a slight expansion of the zone of Ihh expression. "
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    Developmental Biology 02/2009; 328(1):40-53. DOI:10.1016/j.ydbio.2009.01.012 · 3.55 Impact Factor
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    • "Whether the decreased expression of the genes Nostrin (LOC329416), Bmper and Pthr1 is a direct effect of deficient FGFR signalling remains to be elucidated. However, they have been linked to developmental processes during embryogenesis (Choi et al., 2005; Moser et al., 2003; MacLean and Kronenberg, 2005). Also, the expression of Clic6 and Tcfec was down-regulated at day 1 of 1c6 EB development. "
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