Dobner T, Wolf I, Mai B, Lipp M
Institut für Biochemie, Ludwig-Maximilians-Universität, München, Germany.
DNA Seq. 1991;1(6):409-13. doi: 10.3109/10425179109020799.
A genomic clone containing a novel closely linked human histone H2A/H2B gene pair has been isolated and sequenced along with extensive 5' and 3' flanking regions. Both genes are devoid of introns and code for core histone proteins. The nucleotide sequences are 84% and 87% homologous to the coding regions of a human genomic H2A and H2B gene, respectively. A comparison of the nucleotide-derived amino acid sequences shows that the histone H2A protein corresponds to the human H2A.1 subtype, whereas the H2B histone gene predicts an H2B protein sequence which is almost identical to the histone H2B.2 variant from human and bovine obtained by direct protein sequencing. The 3' flanking regions contain previously identified conserved sequence elements thought to be involved in transcription termination and processing of replication-dependent histone gene poly(A)- mRNAs. Primer extension analyses of the histone mRNAs encoded within this clone demonstrate that both genes are divergently transcribed from a 313 bp intergene promoter region. The spatial arrangement and orientation of two TATA-boxes, four CAAT-boxes, and one H2B-box within this region suggests that the linked genes share common promoter elements for transcriptional regulation.
一个包含新的紧密相连的人类组蛋白H2A/H2B基因对的基因组克隆已被分离并测序,同时还包括其广泛的5'和3'侧翼区域。这两个基因都没有内含子,编码核心组蛋白。核苷酸序列与人类基因组H2A和H2B基因的编码区分别具有84%和87%的同源性。对核苷酸推导的氨基酸序列进行比较表明,组蛋白H2A蛋白对应于人类H2A.1亚型,而H2B组蛋白基因预测的H2B蛋白序列与通过直接蛋白质测序获得的人类和牛的组蛋白H2B.2变体几乎相同。3'侧翼区域包含先前确定的保守序列元件,这些元件被认为参与依赖复制的组蛋白基因多聚腺苷酸化mRNA的转录终止和加工。对该克隆内编码的组蛋白mRNA进行引物延伸分析表明,这两个基因从一个313 bp的基因间启动子区域以不同方向转录。该区域内两个TATA盒、四个CAAT盒和一个H2B盒的空间排列和方向表明,这两个相连的基因共享用于转录调控的共同启动子元件。