Ward W S, Partin A W, Coffey D S
Department of Urology, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Chromosoma. 1989 Sep;98(3):153-9. doi: 10.1007/BF00329678.
The highly condensed and tightly packaged DNA of hamster spermatozoa was found to be organized into topologically constrained DNA loop domains attached at their bases to a nuclear matrix. The loop domains of the sperm nuclei differed from somatic cell loop domains from the same animal in two aspects. Sperm loop domains were 60% smaller than somatic cell loop domains, with an average DNA length of 46 +/- 7 kb in sperm as compared with 76 +/- 11 kb in brain. Secondly, unlike virtually all somatic cell DNA known which is negatively supercoiled, sperm DNA was devoid of detectable supercoiling. The presence of the loop domain structure in the highly condensed DNA of mammalian spermatozoa suggests that this motif is a fundamental aspect of eukaryotic DNA organization.
仓鼠精子中高度浓缩且紧密包装的DNA被发现组织成拓扑结构受限的DNA环结构域，这些环结构域的基部附着于核基质。精子细胞核的环结构域在两个方面与同一动物的体细胞环结构域不同。精子环结构域比体细胞环结构域小60%，精子中DNA平均长度为46±7kb，而脑中为76±11kb。其次，与几乎所有已知的呈负超螺旋的体细胞DNA不同，精子DNA没有可检测到的超螺旋。哺乳动物精子高度浓缩的DNA中存在环结构域结构，这表明该基序是真核生物DNA组织的一个基本方面。
