| First Author | Wörsdörfer P | Year | 2017 |
| Journal | Stem Cells | Volume | 35 |
| Issue | 4 | Pages | 859-871 |
| PubMed ID | 27870307 | Mgi Jnum | J:260066 |
| Mgi Id | MGI:6093067 | Doi | 10.1002/stem.2545 |
| Citation | Worsdorfer P, et al. (2017) Abrogation of Gap Junctional Communication in ES Cells Results in a Disruption of Primitive Endoderm Formation in Embryoid Bodies. Stem Cells 35(4):859-871 |
| abstractText | Gap junctional intercellular communication (GJIC) has been suggested to be involved in early embryonic development but the actual functional role remained elusive. Connexin (Cx) 43 and Cx45 are co-expressed in embryonic stem (ES) cells, form gap junctions and are considered to exhibit adhesive function and/or to contribute to the establishment of defined communication compartments. Here, we describe the generation of Cx43/Cx45-double deficient mouse ES cells to achieve almost complete breakdown of GJIC. Cre-loxP induced deletion of both, Cx43 and Cx45, results in a block of differentiation in embryoid bodies (EBs) without affecting pluripotency marker expression and proliferation in ES cells. We demonstrate that GJIC-incompetent ES cells fail to form primitive endoderm in EB cultures, representing the inductive key step of further differentiation events. Lentiviral overexpression of either Cx43 or Cx45 in Cx43/45 mutants rescued the observed phenotype, confirming the specificity and indicating a partially redundant function of both connexins. Upon differentiation GJIC-incompetent ES cells exhibit a strikingly altered subcellular localization pattern of the transcription factor NFATc3. Control EBs exhibit significantly more activated NFATc3 in cellular nuclei than mutant EBs suggesting that Cx-mediated communication is needed for synchronized NFAT activation to induce orchestrated primitive endoderm formation. Moreover, pharmacological inhibition of NFATc3 activation by Cyclosporin A, a well-described inhibitor of calcineurin, phenocopies the loss of GJIC in control cells. Stem Cells 2017;35:859-871. |
