Tolerance of dividing cells to replication stress in UVB-irradiated Arabidopsis roots:: Requirements for DNA translesion polymerases η and ζ
Tolerance of dividing cells to replication stress in UVB-irradiated Arabidopsis roots:: Requirements for DNA translesion polymerases η and ζ
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DOI：
10.1016/j.dnarep.2007.03.004
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发表时间：
2007-09-01
期刊：
影响因子：
3.8
通讯作者：
Hays, John B.
中科院分区：
文献类型：
--
作者：
Curtis, Marc J.;Hays, John B.
在多细胞生物的组织中，阻断复制的DNA损伤可以破坏驱动生长的瞬时扩增（TA）细胞和干细胞的分裂。为了研究组织生长如何在DNA损伤的情况下保持，干细胞和其他细胞类型必须能够清楚地识别。在植物中，根的生长直接取决于根分生组织中的细胞分裂。在拟南芥中，根分生组织中的细胞身份通过相对于静止中心的位置明确地定义，并且通过显微镜容易地可视化。我们评估了两种DNA translesion聚合酶AtPol-eta（Eta）和AtPol zeta（Zeta）在分裂根细胞对模型基因毒素UVB辐射的抗性中的作用。DNA中的主要紫外光产物环丁烷嘧啶二聚体（CPD）被诱导到大约0.03 CPD/kb的阈值剂量（0.28 kJ m（-2）），对野生型根的影响最小。在缺乏AtPol eta和/或AtPol zeta的根中，该剂量抑制细胞分裂和组织生长，并特异性地杀死干细胞;所有三种表型的严重程度以eta（-）< zeta（-）的顺序增加。
In tissues of multicellular organisms, DNA lesions that block replication can disrupt division of the transiently amplifying (TA) cells and stem cells that drive growth. To study how tissue growth is maintained despite DNA damage, stem cells and other cell types must be clearly identifiable. in plants, root growth depends directly on cell divisions in the root meristem. In Arabidopsis thaliana, cell identities in root meristems are unambiguously defined by position relative to the quiescent center and are readily visualized by microscopy We evaluated roles of two DNA translesion polymerases, AtPol-eta (Eta) and AtPol zeta (Zeta), in resistance of dividing root cells to a model genotoxin, UVB-radiation. The major UV photoproducts in DNA, cyclobutane pyrimidine dimers (CPDs), were induced to roughly 0.03 CPD/kb by a threshold dose (0.28 kJ m(-2)) that minimally affected wild-type roots. In roots lacking AtPol eta and/or AtPol zeta this dose inhibited cell division and tissue growth and specifically killed stem cells; severities of all three phenotypes increased in the order eta(-) < zeta(-)