Jayawardene N, Riggs C D
Department of Botany, University of Toronto, Ontario, Canada.
Eur J Biochem. 1994 Jul 15;223(2):693-9. doi: 10.1111/j.1432-1033.1994.tb19042.x.
A tomato genomic clone has been identified which encodes histone H1. The deduced polypeptide is 287 amino acids in length, and exhibits the tripartite organization typical of histones H1. The central globular domain is highly similar to those regions from other H1 molecules, and the carboxyl-terminal domain contains a repeating hexapeptide motif, variants of which are conserved among H1 molecules. RNA gel blotting revealed that histone H1 mRNA is expressed at higher levels in organs which contain meristematic tissue and/or which have a high proportion of actively cycling cells. DNA gel blotting and dot-blot hybridization studies revealed that histone H1 in tomato is encoded by a small gene family. By employing the polymerase chain reaction on genomic DNA and on cDNA, it was determined that the gene is interrupted by an intron. The location and approximate length of the intron are conserved in both the tomato and Arabidopsis genes, with the intron separating the 'nose' region (encoded by exon 1) from the central globular domain (exon 2). The promoter region was found to contain several conserved sequence motifs which likely participate in the regulation of the gene.
已鉴定出一个编码组蛋白H1的番茄基因组克隆。推导的多肽长度为287个氨基酸，并呈现出组蛋白H1典型的三重结构。中央球状结构域与其他H1分子的相应区域高度相似，羧基末端结构域包含一个重复的六肽基序，其变体在H1分子中保守。RNA凝胶印迹显示，组蛋白H1 mRNA在含有分生组织和/或具有高比例活跃循环细胞的器官中表达水平较高。DNA凝胶印迹和斑点杂交研究表明，番茄中的组蛋白H1由一个小基因家族编码。通过对基因组DNA和cDNA进行聚合酶链反应，确定该基因被一个内含子打断。内含子的位置和大致长度在番茄和拟南芥基因中均保守，内含子将“鼻”区（由外显子1编码）与中央球状结构域（外显子2）分隔开。发现启动子区域包含几个可能参与基因调控的保守序列基序。
