Morris R L, Keller L R, Zweidler A, Rizzo P J
Biology Department, Texas A&M University, College Station 77843.
J Protozool. 1990 Mar-Apr;37(2):117-23. doi: 10.1111/j.1550-7408.1990.tb05880.x.
Chromatin spreads made from isolated nuclei of the unicellular green alga Chlamydomonas reinhardtii show the beaded fibers typical of eukaryotic polynucleosomes. Micrococcal nuclease digestions confirmed the presence of nucleosomes with a repeat length of 189 base pairs, essentially the same as typical mammalian cells. Basic nuclear proteins extracted from isolated nuclei or chromatin with 1 M calcium chloride and 0.3 M hydrochloric acid are resolved into seven major components by electrophoresis in the presence of sodium dodecyl sulfate (SDS). These seven components were subjected to qualitative peptide mapping with V8 protease on SDS gels for comparison with the major histone components of calf thymus. Finally, the C. reinhardtii basic nuclear proteins were fractionated by reversed phase high performance liquid chromatography and their amino acid composition determined. From these studies, we conclude that C. reinhardtii has a full complement of the five histones with properties very similar to those of both higher animals and higher plants.
由单细胞绿藻莱茵衣藻分离出的细胞核制备的染色质铺展显示出真核多聚核小体典型的串珠状纤维。微球菌核酸酶消化证实存在重复长度为189个碱基对的核小体，这与典型的哺乳动物细胞基本相同。用1M氯化钙和0.3M盐酸从分离出的细胞核或染色质中提取的碱性核蛋白，在十二烷基硫酸钠（SDS）存在下通过电泳可分离为七个主要成分。对这七个成分在SDS凝胶上用V8蛋白酶进行定性肽图谱分析，以便与小牛胸腺的主要组蛋白成分进行比较。最后，通过反相高效液相色谱法对莱茵衣藻碱性核蛋白进行分级分离，并测定其氨基酸组成。从这些研究中，我们得出结论，莱茵衣藻具有完整的五种组蛋白，其性质与高等动物和高等植物的组蛋白非常相似。
