Organization of highly repetitive satellite DNA of two Cucurbitaceae species (Cucumis melo and Cucumis sativus).
Organization of highly repetitive satellite DNA of two Cucurbitaceae species (Cucumis melo and Cucumis sativus).
复制标题
两种葫芦科物种（甜瓜和黄瓜）的高度重复卫星 DNA 的组织。
DOI：
10.1093/nar/10.2.631
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发表时间：
1982
影响因子：
14.9
通讯作者：
J. Stadler
中科院分区：
文献类型：
--
作者：
V. Hemleben;B. Leweke;A. Roth;J. Stadler
葫芦科（Cucumis melo，甜瓜）和黄瓜（Cucumis sativus，黄瓜）的突出卫星序列已被鉴定，在放线菌素/CsCl梯度中，卫星序列可与核糖体、细胞器和主带DNA分离，其位置不同表明GC含量不同。纯化后的甜瓜卫星经HindIII切割成380 bp的重复单元；AluI消化产生两个条带（大小约为80和220 bp）。如果将HindIII重复单元克隆到pBR325中，则显示出新的HpaII识别位点，留下150和80 bp的两条条带，表明未克隆材料中的C/CGG切割位点发生了甲基化。限制性内切模式表明在380 bp的HindIII片段中存在内部序列重复。C. sativus卫星被AluI切割成180 bp的重复单元，迄今为止没有其他限制性内切酶的识别位点。通过交叉杂交研究，发现甜瓜与红花卫星的序列同源性约为10%。在C. sativus的卫星体和核糖体DNA中检测到高的胞嘧啶甲基化程度（约30%）。幼苗发育过程中未发现甜瓜卫星的转录产物。
The prominent satellites of the Cucurbitaceae Cucumis melo (melon) and Cucumis sativus (cucumber) have been characterized, in actinomycin/CsCl gradients where the satellite sequences can be separated from ribosomal, organelle, and main band DNA the location of the satellites is different indicating a different GC content. The purified satellite of C. melo is cut by HindIII into a repeat unit of 380 bp; AluI digestion gives rise to two bands (about 80 and 220 bp in size). The HindIII repeat unit if cloned into pBR325 exhibits new recognition sites for HpaII leaving two bands with 150 and 80 bp suggesting methylation of the C/CGG cutting site in the uncloned material. The restriction pattern indicates an internal sequence repeat within the 380 bp HindIII fragment. The C. sativus satellite is cut by AluI to a repeat unit of 180 bp showing no other recognition site for the restriction enzymes tested so far. About 10% sequence homology has been determined between the C. melo and C. sativus satellites by cross hybridization studies. A high methylation degree of cytosines has been measured for both satellites and the ribosomal DNA of C. sativus (about 30%). No transcription products of the C. melo satellite were found during seedling development.