Genetic and Biochemical Studies of Ribonucleases H

核糖核酸酶H（RNase H）基因和/或其活性已被确定在所有系统的研究，迄今为止，从古细菌到人。这表明，他们可能是有限的活动所需的最低限度的生物生命之一。 多种RNase H同种型存在于原核生物和真核生物中，并且都以其降解RNA：DNA异源双链体的RNA链的能力而闻名。 这种简单的功能暗示了这些酶在DNA复制、RNA转录、染色质超微结构以及病毒和细胞逆转录过程中调节RNA：DNA双链体的形成。 多种核糖核酸酶H异构体的存在也表明，在一个系统中了解到的异构体可能与我们对其他地方异构体结构和功能的理解有关。 这里描述的研究是广泛的范围内显着的，影响保守和新的作用，核糖核酸酶H在所有生物系统。 此外，他们还利用了布氏锥虫的遗传学，该系统一直是揭示不寻常的核酸代谢事件（如RNA编辑和RNA反式剪接）的原型。

Ribonuclease H (RNase H) genes and/or their activities have been identified in all systems studied to date ranging from archaebacteria to man. This suggests that they may be one of a limited number of activities required for minimal biological life. Multiple RNase H isoforms exist in prokaryotes and eukaryotes and all known for their ability to degrade the RNA strands of RNA:DNA heteroduplexes. This simple function implicates the enzymes in regulating RNA:DNA duplex formation during DNA replication, RNA transcription, chromatin ultrastructure and viral and cellular reverse transcription. The existence of multiple RNase H isoforms also suggest that what is learned of isoforms in one system may relate to our understanding of isoform structure and function elsewhere. The studies described here are broadly significant in scope, impacting conserved and novel roles for ribonucleases H in all biological systems. Furthermore,they exploit the genetics of Trypanosoma brucei, a system that has been the prototype for unmasking unusual nucleic acid metabolic events such as RNA editing and RNA trans-splicing.