title: The SINA E3 ligase OsDIS1 negatively regulates drought response in rice.
abstract: Ubiquitin-regulated protein degradation is a critical regulatory mechanism that controls a wide range of biological processes in plants. Here, we report that OsDIS1 (for Oryza sativa drought-induced SINA protein 1), a C3HC4 RING finger E3 ligase, is involved in drought-stress signal transduction in rice (O. sativa). The expression of OsDIS1 was up-regulated by drought treatment. In vitro ubiquitination assays showed that OsDIS1 possessed E3 ubiquitin ligase activity and that the conserved region of the RING finger was required for the activity. Transient expression assays in Nicotiana benthamiana leaves and rice protoplasts indicated that OsDIS1 was localized predominantly in the nucleus. Overexpression of OsDIS1 reduced drought tolerance in transgenic rice plants, while RNA interference silencing of OsDIS1 enhanced drought tolerance. Microarray analysis revealed that a large number of drought-responsive genes were induced or suppressed in the OsDIS1 overexpression plants under normal and drought conditions. Yeast two-hybrid screening showed that OsDIS1 interacted with OsNek6 (for O. sativa NIMA-related kinase 6), a tubulin complex-related serine/threonine protein kinase. Coexpression assays in N. benthamiana leaves indicated that OsNek6 was degraded by OsDIS1 via the 26S proteasome-dependent pathway and that this degradation was abolished by the OsDIS1(H71Y) mutation, which is essential for its E3 ligase activity. Together, these results demonstrate that OsDIS1 plays a negative role in drought stress tolerance through transcriptional regulation of diverse stress-related genes and possibly through posttranslational regulation of OsNek6 in rice.
authors: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha Hunan 410128, China.
authors: Yuese
authors: Y
authors: Ning
authors: Chachawan
authors: C
authors: Jantasuriyarat
authors: Qingzhen
authors: Q
authors: Zhao
authors: Huawei
authors: H
authors: Zhang
authors: Songbiao
authors: S
authors: Chen
authors: Jinling
authors: J
authors: Liu
authors: Lijing
authors: L
authors: Liu
authors: Sanyuan
authors: S
authors: Tang
authors: Chan Ho
authors: CH
authors: Park
authors: Xuejun
authors: X
authors: Wang
authors: Xionglun
authors: X
authors: Liu
authors: Liangying
authors: L
authors: Dai
authors: Qi
authors: Q
authors: Xie
authors: Guo-Liang
authors: GL
authors: Wang
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers; D055864:Droughts; D017343:Genes, Plant; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D034622:RNA Interference; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D044767:Ubiquitin-Protein Ligases