Throughout development cells make the decision to proliferate, arrest or die. Control of this process is essential for normal development, with unrestrained cell proliferation and cell death underling the origin and progression of disease. The cell-cycle is tightly regulated by a number of factors including the cyclin-dependent kinase inhibitor 1A (Cdkn1a), termed p21 (or Cip1 or WAF1). p21 acts as a negative regulator of cell-cycle progression by binding and inhibiting complexes formed between the cyclin-dependent kinases and their catalytic partners the cyclins. In this report we identify the temporal spatial expression profile of p21 in the developing mid-term mouse embryo using a p21-LacZ reporter mouse line. Expression of p21 was restricted to specific regions with a correspondence to both areas of terminal differentiation and active remodelling. A complex temporal and spatial relationship between p21 expression and regions of apoptosis was evident. A protective role with regard to apoptosis for p21 is proposed.
Apoptosis Cell-cycle Interdigit zone OPT LacZ p21
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We are grateful to the animal care staff for their assistance in this project. This work was funded by the BBSRC through a CASE award with CXR Biosciences LTD to DV and ISPG support to CBAW.
Supplementary Fig. 1 LacZ staining in p21-LacZ and non transgenic 14.5 dpc embryos. LacZ staining was carried out on 14.5 dpc embryos of p21-LacZ and non transgenic CBA/C57BL/6 genetic background. Staining was detected in various regions of the p21-LacZ embryo while no staining was detected in the non transgenic embryo, n = 3 (TIFF 539 kb)
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