Anan'ev E V, Barskiĭ V E
Mol Biol (Mosk). 1975 Sep-Oct;9(5):752-60.
Duration of replication period and relative content of DNA and chromosomal newly-synthesized RNA were determined in nine sites of the region 1A1-3C8 in the polytene X-chromosome of D. melanogaster. Determination of DNA content by cytophotometry of Feulgen stained preparations and by autoradiography after long-term [3H]thymidine labeling gave similar results for all nine sites. The smallest portion of the chromosome in which DNA content could be measured by cytophotometry was about 2-10 bands. The mean DNA content per one band measured separately in 25 sites of the 1A1-3C8 region containing 109 bands differs in 8 times. Calculations show that different chromomeres of elementary chromosome (chromatide) contained from 8 to 65 X 10(3) bases pairs. No additional DNA replication was shown to be involved in the process of 2B region puffing. The duration of replication period was found to correlate negatively with the level of the transcription rate in nine sites of the 1A1-3C8 region of the X-chromosome (r = -0.65). The transcription rate correlates negatively with the DNA content in the largest band for each of nine sites. No significant correlation was obtained between duration of replication period and DNA content in the largest band for each of nine regions.
在黑腹果蝇多线X染色体1A1 - 3C8区域的9个位点测定了复制期的持续时间以及DNA和染色体新合成RNA的相对含量。通过对福尔根染色制剂进行细胞光度测定以及在长期[³H]胸腺嘧啶核苷标记后进行放射自显影来测定DNA含量，这两种方法对所有9个位点都给出了相似的结果。通过细胞光度测定能够测量DNA含量的最小染色体部分约为2 - 10条带。在包含109条带的1A1 - 3C8区域的25个位点分别测量的每条带的平均DNA含量相差8倍。计算表明，初级染色体（染色单体）的不同染色粒含有8到65×10³个碱基对。未发现2B区域胀泡过程涉及额外的DNA复制。发现复制期的持续时间与X染色体1A1 - 3C8区域9个位点的转录速率水平呈负相关（r = -0.65）。转录速率与9个位点中每个位点最大条带中的DNA含量呈负相关。在9个区域中每个区域的复制期持续时间与最大条带中的DNA含量之间未获得显著相关性。
