Phenotype Image Detail

Image

Caption

Ctcf^tm1.1Gfili/Ctcf^tm1.1Gfili embryos fail to develop beyond the E3.5 stage and undergo apoptosis. (A) Ex vivo outgrowth of E3.5 embryos. Blastocysts (E3.5) were isolated from heterozygous (Ctcf +/-) intercrosses and cultured ex vivo for the indicated number of days. At the end of the culture period the embryos were harvested and PCR genotyping and RT-PCR performed. The cultured wild-type (WT) and heterozygous embryos outgrew to form an inner cell mass (ICM) and trophoectoderm (TE) while little proliferation was noted in the cultured homozygous (Ctcf -/-) mutant embryos (40X). (B) E3.5 blastocyst stage embryos isolated from the indicated crosses were subjected to DAPI staining and anti-CTCF immunochemistry (40X). All (16/16) embryos analyzed from the heterozygous intercrosses were positive for CTCF protein expression, displaying staining patterns similar to the two representative embryos shown here. The expected Mendelian ratio of genotypes in such crosses indicates that the chance that none of these 16 embryos were homozygous is less than 0.05 (i.e. (3/4)¹⁶=/~0.01). (C) Day two outgrowths of E3.5 embryos of the indicated genotype. Blastocysts (E3.5) were cultured ex vivo for two days and then subjected to DAPI staining, anti-CTCF immunohistochemistry and TUNEL assay (40X). WT and heterozygous embryos outgrew and expressed CTCF, while cultured homozygous embryos failed to outgrow and exhibited loss of CTCF protein expression and increased apoptosis. The observations displayed here involve one WT and two mutant homozygous embryos cultured ex vivo and are representative of over 60 embryos that were analyzed from heterozygous intercrosses.

Copyright

This image is from Moore JM, PLoS One 2012;7(4):e34915, and is displayed under the terms of the Creative Commons Attribution 4.0 International License. J:211097

Associated Alleles

Symbol	Name
Ctcf^tm1.1Gfili	CCCTC-binding factor; targeted mutation 1.1, Galina Filippova

Associated Genotypes

Allelic Composition	Genetic Background
Ctcf^tm1.1Gfili/Ctcf^tm1.1Gfili	involves: 129S4/SvJaeSor * C57BL/6