Periodic expression of nuclear and mitochondrial DNA replication genes during the trypanosomatid cell cycle.
Periodic expression of nuclear and mitochondrial DNA replication genes during the trypanosomatid cell cycle.
复制标题
锥虫细胞周期期间核和线粒体 DNA 复制基因的周期性表达。
作者：
S. Pasion;G. W. Brown;Lisa M. Brown;D. Ray
在锥虫中，细胞核和单个鞭毛体（或动基体）中的DNA复制几乎同时启动，表明细胞核和鞭毛体的DNA合成（S）期受到协调调节。为了研究核和线粒体DNA合成阶段之间的时间联系的基础上，DNA连接酶I，复制蛋白A，二氢叶酸还原酶和线粒体II型拓扑异构酶的51和28 kDa的亚基编码的基因的表达进行了分析，在同步培养的Crithidia fasciculata的细胞周期进程。这些DNA复制基因都是周期性表达的，在同步化培养物中，mRNA水平的峰值正好发生在DNA合成的峰值之前或峰值时。发现其中通过插入NEO耐药盒破坏编码线粒体拓扑异构酶的基因TOP2的质粒克隆（pdN-1）表达截短的TOP2 mRNA和截短的拓扑异构酶多肽。截短的mRNA也周期性地表达，与内源性TOP2 mRNA的表达协调，表明周期性表达所必需的顺式元件包含在克隆序列内。TOP2和核DNA复制基因在G1/S边界的表达表明，这些基因的调节表达可能在协调锥虫核和线粒体S期中发挥作用。
In trypanosomatids, DNA replication in the nucleus and in the single mitochondrion (or kinetoplast) initiates nearly simultaneously, suggesting that the DNA synthesis (S) phases of the nucleus and the mitochondrion are coordinately regulated. To investigate the basis for the temporal link between nuclear and mitochondrial DNA synthesis phases the expression of the genes encoding DNA ligase I, the 51 and 28 kDa subunits of replication protein A, dihydrofolate reductase and the mitochondrial type II topoisomerase were analyzed during the cell cycle progression of synchronous cultures of Crithidia fasciculata. These DNA replication genes were all expressed periodically, with peak mRNA levels occurring just prior to or at the peak of DNA synthesis in the synchronized cultures. A plasmid clone (pdN-1) in which TOP2, the gene encoding the mitochondrial topoisomerase, was disrupted by the insertion of a NEO drug-resistance cassette was found to express both a truncated TOP2 mRNA and a truncated topoisomerase polypeptide. The truncated mRNA was also expressed periodically coordinate with the expression of the endogenous TOP2 mRNA indicating that cis elements necessary for periodic expression are contained within cloned sequences. The expression of both TOP2 and nuclear DNA replication genes at the G1/S boundary suggests that regulated expression of these genes may play a role in coordinating nuclear and mitochondrial S phases in trypanosomatids.
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分离编码 Crithidia fasciculata 复制蛋白 A 的 51 千道尔顿和 28 千道尔顿亚基的基因。
影响因子：
1.5
作者：
Brown,GW;Hines,JC;Fisher,P;Ray,DS
通讯作者：
Ray,DS
Crithidia fasciculata 双功能二氢叶酸还原酶-胸苷酸合酶基因的结构、基因组组织和转录。
影响因子：
1.5
作者：
Hughes,DE;Shonekan,OA;Simpson,L
通讯作者：
Simpson,L
影响因子：
10.5
作者：
LEBOWITZ, JH;SMITH, HQ;BEVERLEY, SM
通讯作者：
BEVERLEY, SM
锥虫 Crithidia fasciculata 中 DNA 复制蛋白 A 的结构和功能的保守性。
DOI：
10.1073/pnas.89.21.10227
发表时间：
1992
影响因子：
11.1
作者：
Brown,GW;Melendy,TE;Ray,DS
通讯作者：
Ray,DS
DOI：
--
发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Kitchin,PA;Klein,VA;Fein,BI;Englund,PT
通讯作者：
Englund,PT