Read, Write, Adapt: Challenges and Opportunities during Kinetoplastid Genome Replication.
Read, Write, Adapt: Challenges and Opportunities during Kinetoplastid Genome Replication.
复制标题
DOI：
10.1016/j.tig.2020.09.002
复制
发表时间：
2021-01
影响因子：
11.4
通讯作者：
McCulloch, Richard
中科院分区：
文献类型：
--
作者：
Damasceno, Jeziel D.;Marques, Catarina A.;Black, Jennifer;Briggs, Emma;McCulloch, Richard
所有生物体的基因组在其生长和发育过程中被读取，在细胞分裂期间产生新的拷贝，并编码由基因组内容决定的细胞活动。然而，基因组不是不变的信息存储库，而是有目的地以微小和主要的方式改变，适应细胞行为并推动进化。动质体是真核微生物，其显示出广泛的这种读写基因组活动，在许多情况下影响其生物学的关键方面，例如宿主适应。在这里，我们讨论了在两个研究良好的动质体寄生虫，布氏锥虫和利什曼原虫的读写基因组变化的范围，集中在最近的工作表明，这种适应性基因组变异与寄生虫用于复制其非常规基因组的新策略。多顺反子转录控制并塑造动质体基因组，不可避免地导致与DNA复制的冲突。通过利用由此产生的DNA损伤进行适应，动质体具有动态读写基因组变异的巨大潜力。DNA复制的主要起点局限于布氏锥虫和利什曼原虫基因组中的多顺反子转录单位的边界，从而限制DNA损伤。亚端粒可能缺乏这种排列，产生读写热点。于T.在布鲁氏菌中，高度转录的亚端粒变体表面糖蛋白（VSG）表达位点的早期复制可能确保该位点内的复制-转录冲突以触发DNA重组，这是抗原变异的关键事件。利什曼原虫基因组显示出广泛的非整倍性和拷贝数变异。值得注意的是，DNA复制需要重组因子并依赖于亚端粒的S期后复制。分区DNA复制程序的演变支持动质体基因组生物学的重要方面，说明巩固的基因组维护策略，以促进基因组的可塑性。
The genomes of all organisms are read throughout their growth and development, generating new copies during cell division and encoding the cellular activities dictated by the genome’s content. However, genomes are not invariant information stores but are purposefully altered in minor and major ways, adapting cellular behaviour and driving evolution. Kinetoplastids are eukaryotic microbes that display a wide range of such read–write genome activities, in many cases affecting critical aspects of their biology, such as host adaptation. Here we discuss the range of read–write genome changes found in two well-studied kinetoplastid parasites, Trypanosoma brucei and Leishmania, focusing on recent work that suggests such adaptive genome variation is linked to novel strategies the parasites use to replicate their unconventional genomes. Polycistronic transcription dominates and shapes kinetoplastid genomes, inevitably leading to clashes with DNA replication. By harnessing the resultant DNA damage for adaptation, kinetoplastids have huge potential for dynamic read–write genome variation. Major origins of DNA replication are confined to the boundaries of polycistronic transcription units in the Trypanosoma brucei and Leishmania genomes, putatively limiting DNA damage. Subtelomeres may lack this arrangement, generating read–write hotspots. In T. brucei, early replication of the highly transcribed subtelomeric variant surface glycoprotein (VSG) expression site may ensure replication-transcription clashes within this site to trigger DNA recombination, an event critical for antigenic variation. Leishmania genomes show extensive aneuploidy and copy number variation. Notably, DNA replication requires recombination factors and relies on post-S phase replication of subtelomeres. Evolution of compartmentalised DNA replication programmes underpin important aspects of genome biology in kinetoplastids, illustrating the consolidation of genome maintenance strategies to promote genome plasticity.
登录
查看更多内容
影响因子：
2.6
作者：
Cestari I;Stuart K
通讯作者：
Stuart K
DOI：
10.1038/nrmicro2145
发表时间：
2009-07
期刊：
Nature reviews. Microbiology
影响因子：
--
作者：
通讯作者：
--
影响因子：
64.5
作者：
Akiyoshi B;Gull K
通讯作者：
Gull K
影响因子：
4.5
作者：
Damasceno, Jeziel D.;Reis-Cunha, Joao;McCulloch, Richard
通讯作者：
McCulloch, Richard
影响因子：
3.6
作者：
Damasceno JD;Obonaga R;Santos EV;Scott A;McCulloch R;Tosi LR
通讯作者：
Tosi LR