STCH4/REIL2 Confers Cold Stress Tolerance in Arabidopsis by Promoting rRNA Processing and CBF Protein Translation

First author: Hasi Yu; Affiliations: CAS Center of Excellence in Molecular Plant Sciences (中科院上海植物逆境生物学研究中心): Shanghai, China

Corresponding author: Jian-Kang Zhu

Plants respond to cold stress by inducing the expression of transcription factors that regulate downstream genes to confer tolerance to freezing. We screened an Arabidopsis transfer DNA (T-DNA) insertion library and identified a cold-hypersensitive mutant, which we named stch4 (sensitive to chilling 4). STCH4/REIL2 encodes a ribosomal biogenesis factor that is upregulated upon cold stress. Overexpression of STCH4 confers chilling and freezing tolerance in Arabidopsis. The stch4 mutation reduces CBF protein levels and thus delayed the induction of C-repeat-binding factor (CBF) regulon genes. Ribosomal RNA processing is reduced in stch4 mutants, especially under cold stress. STCH4 associates with multiple ribosomal proteins, and these interactions are modulated by cold stress. These results suggest that the ribosome is a regulatory node for cold stress responses and that STCH4 promotes an altered ribosomal composition and functions in low temperatures to facilitate the translation of proteins important for plant growth and survival under cold stress.

植物通过诱导某些特定转录因子的表达来响应低温胁迫，而这些转录因子下游的靶基因赋予了植物的耐冻性。作者筛选了拟南芥T-DNA插入突变体库，鉴定了一个对于低温超敏感的突变体，命名为stch4。STCH4/REIL2基因编码一个核糖体生物发生因子，该基因在低温胁迫时上调表达。过表达STCH4基因能够赋予转基因拟南芥植株较高的低温和冰冻抗性。stch4突变降低了CBF蛋白的丰度，因此也延迟了C-重复序列结合因子CBF调节基因的诱导表达。核糖体RNA加工在stch4突变体中明显减少，尤其是在低温胁迫条件下。STCH4与多个核糖体蛋白相关，这些互作受到低温胁迫的调控。本文的结果揭示了核糖体是拟南芥低温胁迫响应的一个调控支点，STCH4通过促进核糖体组成的改变，在低温条件下促进对植物生长和存活至关重要的蛋白的翻译。

通讯：朱健康（http://sourcedb.sibs.cas.cn/zw/rck/201206/t20120615_3598633.html）

个人简介：1983-1987年，北京农业大学，土壤农业化学学士；1987-1990年，加州大学河滨分校，植物学硕士；1990-1993年，普度大学，植物生理学博士；1994年，洛克菲勒大学，分子生物学博士后。

研究方向：渗透胁迫的感应和信号传导；低温胁迫的感应和信号传导；耐盐和耐氧化的机制；RNA介导的DNA甲基化；DNA去甲基化及其调控。

doi: https://doi.org/10.1016/j.celrep.2019.12.012

Journal: Cell Reports

Published date: January 07, 2020