Possible signals from the A and O polar blastomeres to the lateral ectoderm

Inductive interactions:
Possible signals from the A and O polar blastomeres to the lateral ectoderm

INDUCER:	Polar oral and aboral blastomeres
TARGET:	Lateral blastomeres
STAGE:	Mid-late cleavage
INDUCTION OUTCOME:	Specification of animal blastomeres across the O/A axis
PROOFS:
SPECIES:	Strongylocentrotus purpuratus
COMMENTS:	At mid-late cleavage individual blastomeres in the lateral regions dive rise to both oral and aboral clones. This is not true for the polar blastomeres, which generate either all oral or all aboral clones. Thus, specification across the O/A axes may be progressive, this raises the possibility that additional signals emanate from the polar oral and aboral blastomeres
REFERENCE:	Cameron et al., 1987, Cameron et al., 1993