Strongylocentrotus purpuratus Genes in Development:
Metallothionein genes
SpMTA
Function
The SpMTA is a metallothionein (MT) gene of the sea urchin.
(Harlow et al., 1989).
Protein
Metallothioneins are small, cysteine-rich proteins
comprised largely of heavy metal-binding domains (Nemer et al., 1991).
SWISS_PROT: P04734
Subcellular location
Expression Pattern
More than 95 % of the inherited maternal MT RNA and >90 %
of the MT mRNA synthesized by Strongylocentrotus
purpuratus embryos is MTA.
The virtual absence of endogenous MTA mRNA accumulation
and transcription of MT genes in embryos cultured in
chelator indicates that MT gene expression in this system
depends largely, if not entirely, on the involvement
of heavy-metal ions (Harlow et al., 1989).
Transcripts of the SpMTA metallothionein (MT) gene begin to accumulate at
the 10-12 h blastula stage.
The MTA mRNA rises from ~2 * 10^4 transcripts/egg
to ~2 * 10^5 transcripts/20-h blastula.
MTA mRNA
is restricted to the aboral ectoderm and this same localization
holds for embryos induced with
heavy metal ions (Nemer et al., 1991).
mRNA level
Temporal accumulation
Method: northern blot analysis
Reference: Nemer et al., 1991
Hours post fertilization
0
4
8
12
16
20
24
Level (transcripts per embryo X 10^-5)
0,3
0,3
0,3
0,35
0,7
1,7
2,3
Spatial localization
Method: in situ hybridization
Reference: Nemer et al., 1991