SM37, a skeletogenic gene of the sea urchin embryo linked to the SM50 gene

Abstract

The genomic DNA region that contains the SM50 gene also included a second gene that appeared to encode another skeletogenic matrix protein. The two genes were linked at a distance of about 12 kb. Based on the molecular weight of the implied protein the gene was termed SM37. The SM37 protein included a long tandem sequence of short glycine-rich repeats that was similar to the glycine-rich repeats included in the SM50 protein and several other skeletal matrix proteins, although the sequence of SM37 repeat was distinct. The overall structure of the SM37 protein was similar to SM50 as well. However, SM37 was only about 30% identical in amino acid sequence to SM50, and coding region probes behaved as a single copy sequence under standard conditions. The SM37 gene included the same cis-regulatory elements as the SM50 gene, although in a different order with respect to transcription. This gene was regulated coordinately with SM50 during development, and like SM50 was expressed exclusively in skeletogenic mesenchyme lineages.

Identification and developmental expression of new biomineralization proteins in the sea urchin Strongylocentrotus purpuratus

“…At the late gastrula stage, it was apparent that the level of expression of SpSM29 mRNA varied in different regions of the PMC syncytium. Signal was generally much stronger in the ventrolateral clusters of PMCs than in the dorsal chain, as has been described for SpSM37 and SpSM50 (Lee et al 1999). Signal intensity declined at later stages and we were unable to determine the spatial pattern of SpSM29 expression within the PMC syncytium at the pluteus stage.…”

“…Based on twodimensional gel electrophoretic studies it has been estimated that as many as 40-50 different proteins are associated with the spicule (Killian and Wilt 1996). In the sea urchin, four spicule matrix proteins have been cloned -PM27, SM30, SM37, and SM50 (Benson et al 1987;George et al 1991;Harkey et al 1995;Katoh-Fukui et al 1991;Lee et al 1999). PM27, SM37, and SM50 are predicted to be basic proteins with similar structures.…”

What Genes and Genomes Tell us about Calcium Carbonate Biomineralization

“…Lee et al [28] isolated a cDNA and its cognate genomic sequence that encodes another putative spicule matrix protein designated SM37. They used a genomic clone that included the first exon of SM50 and more than 12 kb of upstream region to screen a cDNA library.…”

Biologia celular da esqueletogênese e processos de mineralização em Holothuroidea (Echinodermata)

“…SM50 e PM27 não são glicolisadas e são abundantes na superfície do ossículo subjacente à célula da membrana (Harkey et al, 1995;Urry et al, 2000;Kitajima et al, 1996;Wilt, 2002). SM37 (Lee et al, 1999) tem uma seqüência de aminoácidos similar à de SM50, se aproximando muito de seu genoma (Wilt, 2002). SM50, SM37, PM27 provavelmente representam uma subfamília de proteínas da matriz de ossículos, baseadas na seqüência primária, com expressão da regulação e localização dentro da espícula (Wilt, 1999;Illies et al, 2002).…”

“…A composição protéica da matriz tem sido estudada em trabalhos baseados em eletroforese bidimensional, se estimando que existam de 40 a 50 diferentes proteínas associadas com os ossículos de equinodermos (Killian e Wilt, 1996). Em ouriços do mar, quatro proteínas de matriz presentes na espícula já foram clonadas -PM27, SM30, SM37 e SM50 (Benson et al, 1987;George et al, 1991;Harkey et al, 1995;Katoh-Fukui et al, 1991;Lee et al, 1999). Sendo que PM27, SM37 e SM50 apresentam estruturas similares e são consideradas como proteínas fundamentais da matriz (Benson et al, 1987).…”