Waterborg J H
Division of Cell Biology and Biophysics, School of Basic Life Sciences, University of Missouri-Kansas City 64110-2499.
Plant Mol Biol. 1992 Jan;18(2):181-7. doi: 10.1007/BF00034947.
Histone H3 proteins were purified to near homogeneity from callus cultures of dicotyledonous plants alfalfa, soybean, Arabidopsis, carrot and tobacco to determine the number of histone H3 variants. In every species two histone H3 variants were identified by gradient gel electrophoresis and reversed-phase chromatography. They were named H3.1 and H3.2 in order of increasing mobility in acid-urea-Triton gels. Co-electrophoresis of histone H3.2 proteins of all species in this gel system and HPLC co-chromatography suggest that all histone H3.2 variants have a primary protein sequence identical to alfalfa H3.2. Two distinct H3.1 variant forms were identified, represented by alfalfa and Arabidopsis H3.1 proteins which differ only at residue 90. Soybean H3.1 resembles H3.1 of alfalfa. Carrot and tobacco H3.1 appear identical to the Arabidopsis H3.1 histone variant. All H3 proteins were acetylated to multiple levels and in each plant the histone H3.2 forms were more highly acetylated. An inverse relationship was observed between plant genome size and the relative abundance of histone variant H3.2 and also with the level of acetylation of both histone H3 variants. This correlation matches the general tendency that in plants with smaller genomes a larger fraction of the genome is transcriptionally active.
从双子叶植物苜蓿、大豆、拟南芥、胡萝卜和烟草的愈伤组织培养物中纯化组蛋白H3至近乎同质，以确定组蛋白H3变体的数量。在每个物种中，通过梯度凝胶电泳和反相色谱法鉴定出两种组蛋白H3变体。它们在酸性尿素 - Triton凝胶中按照迁移率增加的顺序被命名为H3.1和H3.2。在该凝胶系统中对所有物种的组蛋白H3.2蛋白进行共电泳以及HPLC共色谱分析表明，所有组蛋白H3.2变体的一级蛋白序列与苜蓿H3.2相同。鉴定出两种不同的H3.1变体形式，以苜蓿和拟南芥H3.1蛋白为代表，它们仅在第90位残基处不同。大豆H3.1与苜蓿的H3.1相似。胡萝卜和烟草的H3.1似乎与拟南芥的H3.1组蛋白变体相同。所有H3蛋白都被乙酰化到多个水平，并且在每种植物中，组蛋白H3.2形式的乙酰化程度更高。观察到植物基因组大小与组蛋白变体H3.2的相对丰度以及两种组蛋白H3变体的乙酰化水平之间呈负相关。这种相关性与一般趋势相符，即在基因组较小的植物中，基因组中更大比例的区域具有转录活性。
