ABSTRACT
An increasing body of evidence points to significant spatio-temporal differences in early placental development between mouse and human, but a detailed comparison of placentae in these two species is missing. We set out to compare placentae from both species across gestation, with a focus on trophoblast progenitor markers. We found that CDX2 and ELF5, but not EOMES, are expressed in early post-implantation trophoblast subpopulations in both species. Genome-wide expression profiling of mouse and human placentae revealed clusters of genes with distinct co-expression patterns across gestation. Overall, there was a closer fit between patterns observed in the placentae when the inter-species comparison was restricted to human placentae through gestational week 16 (thus, excluding full-term samples), suggesting that the developmental timeline in mouse runs parallel to the first half of human placental development. In addition, we identified VGLL1 as a human-specific marker of proliferative cytotrophoblast, where it is co-expressed with the transcription factor TEAD4. As TEAD4 is involved in trophectoderm specification in the mouse, we posit a regulatory role for VGLL1 in early events during human placental development.
Footnotes
Author contributions
Conceptualization: F.S., L.C.L., M.M.P.; Methodology: F.S., D.P., A.W., M.M.-Z.; Validation: F.S., D.P., O.F., A.W.; Formal analysis: F.S., M.K., C.T., L.C.L.; Investigation: F.S., D.P., A.W.; Resources: F.S., D.P., K.A.N.R., K.K.N., C.-W.C., M.M.-Z., D.R.N.; Writing - original draft: F.S.; Writing - review & editing: M.K., A.W., C.-W.C., L.C.L., M.M.P.; Visualization: F.S., M.M.P.; Supervision: D.R.N., L.C.L., M.M.P.; Funding acquisition: M.M.P.
Funding
This work was supported by the National Institute of Child Health and Human Development (R01-NIH HD07110 to M.M.P.). M.M.P. and L.C.L. were also supported by a grant from the California Institute for Regenerative Medicine (RN3-06396 to M.M.P.). Deposited in PMC for release after 12 months.
