Tebeau C M, Jahn C L
Department of Cell and Molecular Biology, Northwestern University Medical School, Chicago, IL 60611, USA.
Gene. 1997 Sep 15;197(1-2):109-13. doi: 10.1016/s0378-1119(97)00248-5.
Two 1.5-kb macronuclear chromosomes bearing histone H2B genes from the ciliated protozoan Euplotes crassus were cloned and sequenced. Although the noncoding sequences on these macronuclear chromosomes are very different, the genes encode an identical 113-aa histone H2B protein that has a shortened N-terminus and a highly conserved C-terminus relative to histone H2B proteins in other organisms. Primer extension was used to determine the transcription start points. Northern analysis shows that the abundance of H2B mRNA changes relative to DNA replication periods during the sexual phase of the life cycle. Analysis of 3' RACE products indicates that the H2B genes are coexpressed.
克隆并测序了来自纤毛原生动物粗壮真核草履虫的两条携带组蛋白H2B基因的1.5 kb大核染色体。尽管这些大核染色体上的非编码序列差异很大，但这些基因编码一种相同的113个氨基酸的组蛋白H2B蛋白，相对于其他生物体中的组蛋白H2B蛋白，其N端缩短，C端高度保守。采用引物延伸法确定转录起始点。Northern分析表明，在生命周期的有性阶段，H2B mRNA的丰度相对于DNA复制期会发生变化。对3'RACE产物的分析表明，H2B基因是共表达的。
