Sutcliffe J G, Milner R J, Bloom F E, Lerner R A
Proc Natl Acad Sci U S A. 1982 Aug;79(16):4942-6. doi: 10.1073/pnas.79.16.4942.
Several randomly selected cDNA clones made from rat brain polyA+RNA have unusual properties. Although the cDNA inserts are 500-1,250 base pairs long, they hybridize to a 160-nucleotide RNA species that is present in brain but not in liver or kidney. Nucleotide sequence studies of two of the clones and hybridization studies show that a common 82-nucleotide sequence is responsible for the hybridization. The same sequence is located in the second intron of a rat growth hormone gene. These studies suggest that signals called "ID sequences" may be carried in the introns of genes and prescribe their tissue-specific expression.
从大鼠脑多聚腺苷酸（polyA）+RNA制备的几个随机选择的互补DNA（cDNA）克隆具有不同寻常的特性。虽然cDNA插入片段长度为500 - 1250个碱基对，但它们与一种160个核苷酸的RNA分子杂交，这种RNA分子存在于脑中，而不存在于肝脏或肾脏中。对其中两个克隆的核苷酸序列研究和杂交研究表明，一个共同的82个核苷酸的序列负责这种杂交。相同的序列位于大鼠生长激素基因的第二个内含子中。这些研究表明，称为“ID序列”的信号可能存在于基因的内含子中，并决定其组织特异性表达。
