Vol'fson V G, Vorob'ev V I
Mol Biol (Mosk). 1979 Jan-Feb;13(1):47-59.
The degree of divergence of short and long repetitive DNA sequences and single copy DNA of five Echinodermata species (sea urchins, starfish, sea-cucumber) was studied by the method of molecular hybridization. Different fractions of 3H-DNA of the sea urchin Strongylocentrotus intermedius were hybridized with the DNA of other species. Thermal stability of the hybridized DNA molecules was determined. The results obtained suggest that short repetitive sequences were most conservative during the evolution of Echinodermata. Single copy DNA fractions of closely related sea urchin species (S. intermedius and S. nudus) have more homologous sequences than long repetitive DNA fractions of the same species. The DNA of evolutionary distant species (sea urchin and starfish) have more homologous long repetitive sequences than the single copy ones. All DNA fractions of S. intermedius have sequences hybridized with the DNA of all other species studied: short repetitive sequences--55%, long repetitive sequences--20%, single copy sequences--12%.
采用分子杂交方法研究了5种棘皮动物（海胆、海星、海参）短重复DNA序列、长重复DNA序列和单拷贝DNA的分歧程度。用中间球海胆3H-DNA的不同组分与其他物种的DNA进行杂交。测定杂交DNA分子的热稳定性。所得结果表明，短重复序列在棘皮动物进化过程中最为保守。亲缘关系较近的海胆物种（中间球海胆和光棘球海胆）的单拷贝DNA组分比同一物种的长重复DNA组分具有更多的同源序列。进化距离较远的物种（海胆和海星）的DNA长重复序列比单拷贝序列具有更多的同源性。中间球海胆的所有DNA组分都有与所研究的所有其他物种的DNA杂交的序列：短重复序列——55%，长重复序列——20%，单拷贝序列——12%。
