Gene Networks Database

Spec3

Function

Protein

Subcellular location

Expression Pattern

mRNA level

Stage	Egg	Cleavage	Hatching blastula	Mesenchyme blastula	Gastrula	Prism	Pluteus
Level	Low level	Accumulate rapidly	Increase 50-fold	Decline abruptly	Remain constant	Increase	Increase again

The Spec3 mRNA, 2.0 kb in length, is present at low levels in unfertilized eggs but accumulates rapidly during cleavage, increasing 50-fold by hatching blastula stage. Message levels then decline abruptly, remain constant during mesenchyme blastula and gastrula stages, and increase again during prism and pluteus stages.
Deciliation and regeneration of cilia in gastrula-stage embryos results in a four- to fivefold increase in Spec3 mRNA levels, implying that the Spec3 gene product is associated with ciliogenesis (Eldon et al., 1987).

Stage	Early blastula	Late blastula	Gastrula	Pluteus
Tissue	All blastomeres	Ectoderm (animal hemisphere)	Ectoderm	Ciliary band, other ectoderm cells

In situ hybridization shows that although Spec3 message accumulates in all blastomeres at early blastula stages, it later becomes restricted to ectoderm. By late blastula stage, hybridization is strongest in the animal hemisphere.
At gastrula, signals are variable over ectoderm, and by pluteus, grains are concentrated in the ciliary band, though present in other ectodermal cells as well (Eldon et al., 1987).

Sequences

Regulatory Regions

Regulatory Connections

Upstream Genes

Spec3

Downstream Genes

Evolutionary Homologues

• Spec1 Strongylocentrotus purpuratus
• Spec2c Strongylocentrotus purpuratus
• Spec2d Strongylocentrotus purpuratus
• Spec2a Strongylocentrotus purpuratus
• LpS1 Lytechinus pictus
• Spec family genes of other sea urchins

Links

• Urchin Web