Skip to content
Login Register

#4-cell stage

2 public questions tagged with this topic.

Stem Cell -ll

The cells of the 4-cell stage mouse embryo are:

Mammalian embryo displays highly regulative development: early blastomeres retain remarkable flexibility and equipotency. Murine four-cell embryo blastomeres remain totipotent as demonstrated by ability of isolated single cell to contribute to both trophectoderm and inner cell mass compartments and to support full-term development when aggregated with carrier cells or transplanted into foster mothers. Single-nucleus RNA sequencing shows equal expression of Oct4 and Cdx2 potentiality. Potency restriction occurs at compaction and blastocyst stage when Cdx2 and Oct4 become mutually exclusive, sep

Ref: Tarkowski, Nature 1959; Tarkowski & Wroblewska 1967: Mouse 4-cell blastomeres totipotent contribution.

View Details
C-Elegans Development-l

What happens if the P2 blastomere is removed at the 4-cell stage?

P2 blastomere provides inductive Wnt and Src signals to EMS at four-cell stage essential for endoderm. MOM-2 Wnt ligand from P2 activates MOM-5 Frizzled, WRM-1 beta-catenin asymmetry, LIT-1 Nemo kinase cascade in EMS, polarizing division into anterior MS and posterior E daughters. POP-1 TCF nuclear levels reduced posteriorly, permitting MED/END expression. If P2 is ablated surgically or genetically, extrinsic signal disappears, EMS defaults to MS-like fate, both daughters become muscle-pharynx precursors, endoderm marker ges-1 and elt-2 fail. Thus no intestine forms, demonstrating conditional

Ref: Gilbert, Developmental Biology, 12th ed., Chapter 8: P2-EMS interaction - Wnt signaling induces endoderm in C. elegans.

View Details