Developmental Expression of PDGF, TGF-α, and TGF-β Genes in Preimplantation Mouse Embryos

TLDR

Growth and differentiation in mammalian embryos may be regulated by embryonic or maternal growth factors. Single‑cell mRNA profiling was used to examine simultaneous expression of growth‑factor transcripts in preimplantation mouse embryos. PDGF‑A, TGF‑α, and TGF‑β1 transcripts and proteins were detected in blastocysts, with PDGF‑A and TGF‑α present maternally and TGF‑β1 appearing post‑fertilization, indicating these factors likely contribute to early embryo growth and differentiation.

Abstract

Control of growth and differentiation during mammalian embryogenesis may be regulated by growth factors from embryonic or maternal sources. With the use of single-cell messenger RNA phenotyping, the simultaneous expression of growth factor transcripts in single or small numbers of preimplantation mouse embryos was examined. Transcripts for platelet-derived growth factor A chain (PDGF-A), transforming growth factor (TGF)-α, and TGF-β1, but not for four other growth factors, were found in whole blastocysts. TGF-α, TGF-β1, and PDGF antigens were detected in blastocysts by immunocytochemistry. Both PDGF-A and TGF-α were detected as maternal transcripts in the unfertilized ovulated oocyte, and again in blastocysts. TGF-β1 transcripts appeared only after fertilization. The expression of a subset of growth factors in mouse blastocysts suggests a role for these factors in the growth and differentiation of early mammalian embryos.