Int. J. Dev. Biol. 52: 383 - 388 (2008)
doi: 10.1387/ijdb.072448fr
© UBC Press

Calpain 2 expression pattern and sub-cellular localization during mouse embryogenesis

Fabrice Raynaud1, Anne Marcilhac1, Karim Chebli2, Yves Benyamin1 and Mireille Rossel3,*

1Laboratory Cellular Motility EPHE CNRS UMR 5539, University Montpellier, 2IGMM, UMR 5535, IFR122 and 3Laboratory Quantitative Cellular Biology EPHE, Montpellier 34095 INSERM U881 cc103, Montpellier 34095, University Montpellier, France

ABSTRACT Regulation of migration and proliferation by calpain has been shown in various cell types; however, no data are available concerning calpain 2 (capn2) localization in embryonic tissues. Here, we report the expression pattern of capn2 during mouse embryonic development. Expression of the capn2 gene is observed throughout embryonic development. From ES cells and the 8-cell stage to late neurulation stages, CAPN2 is expressed in the cytoplasm and nuclear compartments, with a clear co-localisation with chromatin. Whole-mount in situ hybridization analysis from E8.5 to 14.5 stages indicates high levels of capn2 expression in the nervous system, heart and mesodermal tissues. Up-regulation is maintained during later developmental stages in proliferating cells and in precursor cells involved in muscle (myoblasts) or bone formation (chondrocytes). At later developmental stages, elevated mRNA levels coincided with CAPN2 nuclear localization in these cell types, while differentiated cells maintained cytoplasmic expression. This detailed analysis reveals dynamic expression: nuclear localization was associated either with active cell mitosis in embryonic stem cells and early developmental stages or with precursor cells later during organogenesis. Thus, these data indicate that CAPN2 may represent a key factor in development from the first cell division.

Keywords:

calpain2, mouse embryogenesis, subcellular localisation

*Corresponding author e-mail: mrossel@univ-montp2.fr