Gene Networks Database


Strongylocentrotus purpuratus Genes in Development: Proteases


SuBMP


Function

SuBMP codes for a protein which belongs to the family of huBMP-1 related proteins.
SuBMP may be involved in events leading to biomineralization (spiculogenesis) (Hwang et al., 1994)

Protein

SuBMP protein contains a signal peptide at its N-termini, followed by an activation region, protease (P) domain, a C1r/C1s domain, an imperfect repeat of C1r/C1s domain and an EGF-like domain. The P domain, containing 193 amino acids near the N-terminal region, exhibits 36 % sequence identity with that of the astacin metalloprotease. In this domain suBMP contains the active site consensus sequence typical of metalloendoproteases, namely, HEXXH. The C1r/C1s domain of SuBMP, containing 100 amino acids near the C-terminal region, exhibits 27 % sequence identity with domain I of human C1r and C1s serine proteases in the complement cascade. This domain also shares sequence homology with the C-terminal region of the calcium-dependent serine protease precursor. The IR domain, containing 120 amino acids, is an imperfect repeat of the C1r/C1s domain. The E domain contains a segment of 45 amino acids that shares 42 % sequence identity with human epidermal growth factor (EGF) precursor. This region contains 6 cysteine residues spaced between other conserved residues in the sequence DXCX7CX3CXNX4YXCXCX4EX7C. This spacing of cysteine residues is the same as that found in human EGF precursor, except that in EGF the segment between the first two cysteine residues contains 6 instead of 7 residues (Hwang et al., 1994).
Several, if not all, of the four potential N-linked glycosylation sites in suBMP are glycosylated (Hwang et al., 1994).
SWISS_PROT: P98069

Subcellular location

The immunoelectron microscopy revealed that suBMP was present in the cytoplasm and on the surface of ectodermal, endodermal (gut) and primary mesenchyme (PM) cells. Clusters of SuBMP-antibody complex were also seen on the surface of the cells and within the blastocoel. In this extracellular compartment SuBMP was detected on the surface of filopodia of the PM cells, as well as on elements of the extracellular matrix (Hwang et al., 1994).

Expression Pattern

Although SuBMP mRNA was detectable at a low level in the unfertilized egg, maximal expression of mRNA was observed at hatched blastula stage, with only a modest decrease in level at later stages of development. In situ hybridization studies revealed that suBMP mRNA is found in both ectodermal and PM cells in hatched blastula-stage embryos. Maximal expression of suBMP was observed at hatched blastula stage. A slight decrease in level was observed from mesenchyme blastula to the 72 hour pluteus stage embryo.
A trace level of the protein was found in the unfertilized egg, but not again detected until the blastula stage. The highest level was observed at the mesenchyme blastula stage; a slight decrease in SuBMP was observed at later stages. Apparently, translation of the low level of SuBMP mRNA in the unfertilized egg is repressed because the ratio of expressed protein to mRNA is very low at this stage. (Hwang et al., 1994).

mRNA level

Temporal accumulation

Method: Northern blot analysis
Reference: Hwang et al., 1994

Stage
Egg
Prehatching blastula
Hatched blastula
Mesenchyme blastula
Gastrula
Prism
Pluteus
Level
+
+
+
+
+
+
+

Protein level

Temporal accumulation

Method: Western blot analysis
Reference: Hwang et al., 1994

Stage
Egg
3 hr
6 hr
10 hr
21 hr
24 hr
26 hr
44 hr
57 hr
72 hr
Level
+
-
-
- +
+
+
+
+
+
+


Sequences

GenBank:

Regulatory Regions

Regions

Regulatory Connections

Upstream Genes

SuBMP

Downstream Genes


Evolutionary Homologues


Links

Urchin Web

Bibliography


[Previous]UrchiNet[Up] Search the GeNet
This page is designed byKate G. Savostyanova
Copyright © 1997 GeNet Team