Regulated transcription of the histone H2B genes of Trypanosoma brucei
Regulated transcription of the histone H2B genes of Trypanosoma brucei
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DOI：
10.1046/j.1432-1327.1999.00592.x
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发表时间：
1999-09-01
期刊：
影响因子：
--
通讯作者：
Pays, E
中科院分区：
文献类型：
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作者：
García-Salcedo, JA;Gijón, P;Pays, E
在布氏锥虫中，编码组蛋白 H2B 的基因被组织成每个单倍体基因组约 10-15 个串联拷贝的簇。 H2B转录本经过转拼和聚腺苷酸化处理，编码111个残基、分子量为12.5 kDa的多肽。 H2B mRNA 在寄生虫生命周期中表达差异，并且在分裂的原循环和血流细长形式中的存在水平高于在非分裂的血流粗短形式中。对从短节形式同步分化为前环形式期间 H2B mRNA 水平的分析表明，这些转录物的丰度通过细胞周期进行调节，在 S 期达到最高水平。在培养物中向原环形式添加羟基脲可特异性地将 H2B mRNA 水平降低约两倍，这一效应与其 3' 非翻译区无关。蛋白质合成的抑制阻止了这种减少。
In Trypanosoma brucei, the genes encoding histone H2B are organized in a cluster of about 10-15 tandemly linked copies per haploid genome. The H2B transcripts are processed by trans-splicing and polyadenylation, and encode a polypeptide of 111 residues with a molecular mass of 12.5 kDa. H2B mRNAs are differentially expressed during the parasite life-cycle and are present at higher levels in dividing procyclic and bloodstream slender forms than in the nondividing bloodstream stumpy forms. Analysis of H2B mRNA levels during the synchronous differentiation from stumpy to procyclics forms revealed that the abundance of these transcripts is regulated through the cell-cycle, reaching maximum levels during S-phase. Addition of hydroxyurea to procyclic forms in culture specifically decreased H2B mRNA levels by about twofold, an effect not linked to its 3' untranslated region. Inhibition of protein synthesis prevented this decrease.