Steinemann M
Chromosoma. 1978 Mar 31;66(2):127-39. doi: 10.1007/BF00295135.
The DNAs of five Chironomus species, C. plumosus, C. nuditarsis, C. thummi thummi, C. melanotus, and Camptochironomus pallidivittatus, were investigated in analytical neutral isopycnic CsCl density gradients. DNA was isolated both from larval brains ("diploid-DNA") and salivary glands ("polytene-DNA"). The buoyant densities of mainband DNAs were 1.692 g/cm3, with the exception of C. melanotus whose mainband had a density of 1.693 g/cm3. The densities correspond to a calculated GC content of 33% and 34% respectively. Only in C. melanotus was the DNA clearly resolved into mainband DNA and two distinct satellite shoulders: Satellite I, with a buoyant density of 1.684 g/cm3 (25% GC, calculated) and satellite II of 1.679 g/cm3 (19% GC, calculated). The two satellites comprise 15% of the total DNA in the "diploid-DNA"' and they also occur in the "polytene-DNA", where they make up 11%. The results are discussed in the general context of under- and overreplication in polyploid and polytene cells.
在分析性中性等密度氯化铯密度梯度中研究了五种摇蚊的DNA，即丰满摇蚊、裸足摇蚊、图氏摇蚊指名亚种、黑腹摇蚊和苍白带摇蚊。DNA分别从幼虫脑（“二倍体DNA”）和唾液腺（“多线DNA”）中分离出来。除黑腹摇蚊的主带密度为1.693 g/cm³外，主带DNA的浮力密度均为1.692 g/cm³。这些密度分别对应于计算得出的33%和34%的GC含量。只有在黑腹摇蚊中，DNA才清晰地分为主带DNA和两个明显的卫星峰：卫星I，浮力密度为1.684 g/cm³（计算得出的GC含量为25%），卫星II的浮力密度为1.679 g/cm³（计算得出的GC含量为19%）。这两个卫星峰在“二倍体DNA”中占总DNA的15%，它们也存在于“多线DNA”中，占11%。在多倍体细胞和多线细胞中复制不足和过度复制的一般背景下讨论了这些结果。
