Chen E Y, Zollo M, Mazzarella R, Ciccodicola A, Chen C N, Zuo L, Heiner C, Burough F, Repetto M, Schlessinger D, D'Urso M
Advanced Center for Genetic Technology, Applied Biosystems Division of Perkin Elmer Corp, Foster City, CA 94404, USA.
Hum Mol Genet. 1996 May;5(5):659-68. doi: 10.1093/hmg/5.5.659.
DNA comprising 219 447 bp was sequenced in nine cosmids and verified at > 99.9% precision. Of the standard repetitive elements, 187 Alus make up 20.6% of the sequence, but there were only 27 MERs (2.9%) and 17 L1 fragments (1.6%). This may be characteristic of such high GC (57%) regions. The sequence also includes an 11.3 kb tract duplicated with 99.2% identity at a distance of 38 kb. The region is 80-90% transcribed and 12.5% translated. Thirteen known genes and their exon-intron borders are all accurately predicted at least in part by GRAIL programs, as are six additional genes. From centromere to telomere, the orientation of transcription varies among the first eight genes, then runs centromeric to telomeric for the next five, and is in the opposite sense for the last six. Eighteen of the 19 genes are associated with CpG islands. Two islands are exact copies in the 11.3 kb repeat units, and could thus give rise to double dosage levels of an X-linked gene. Another island is associated with two genes transcribed in opposite directions. From the sequence data, three genes and their exon structure are inferred. One of them, previously associated with HEX2, is shown to be a different gene unrelated to hexokinases; a second gene, previously known by an EST, is plexin, from its 65.5% identity with the Xenopus analog; and a third is a subunit of a vacuolar H-ATPase, and is named VATPS1.
对包含219447个碱基对的DNA在9个黏粒中进行了测序，并以大于99.9%的精度进行了验证。在标准重复元件中，187个Alu元件占序列的20.6%，但只有27个MER（2.9%）和17个L1片段（1.6%）。这可能是此类高GC（57%）区域的特征。该序列还包括一个11.3kb的片段，在38kb的距离处有99.2%的同一性重复。该区域80 - 90%被转录，12.5%被翻译。GRAIL程序至少部分准确预测了13个已知基因及其外显子 - 内含子边界，另外6个基因也是如此。从着丝粒到端粒，前八个基因的转录方向各不相同，接下来五个基因的转录方向是从着丝粒到端粒，最后六个基因的转录方向则相反。19个基因中的18个与CpG岛相关。两个岛在11.3kb的重复单元中是精确拷贝，因此可能导致X连锁基因的双倍剂量水平。另一个岛与两个转录方向相反的基因相关。从序列数据中推断出三个基因及其外显子结构。其中一个先前与HEX2相关，结果表明它是一个与己糖激酶无关的不同基因；第二个基因，先前由一个EST所知，是丛状蛋白，因其与非洲爪蟾类似物有65.5%的同一性；第三个是液泡H - ATPase的一个亚基，命名为VATPS1。
