Mutations in eIF5B Confer Thermosensitive and Pleiotropic Phenotypes via Translation Defects in Arabidopsis thaliana.
Liyuan ZhangXin-Ye LiuKishor GaikwadXiaoxia KouFei WangXuejun TianMingming XinZhongfu NiQixin SunHuiru PengElizabeth VierlingPublished in: The Plant cell (2017)
The conserved eukaryotic translation initiation factor 5B, eIF5B, is a GTPase that acts late in translation initiation. We found that an Arabidopsis thaliana mutant sensitive to hot temperatures 3 (hot3-1), which behaves as the wild type in the absence of stress but is unable to acclimate to high temperature, carries a missense mutation in the eIF5B1 gene (At1g76810), producing a temperature sensitive protein. A more severe, T-DNA insertion allele (hot3-2) causes pleiotropic developmental phenotypes. Surprisingly, Arabidopsis has three other eIF5B genes that do not substitute for eIF5B1; two of these appear to be in the process of pseudogenization. Polysome profiling and RNA-seq analysis of hot3-1 plants show delayed recovery of polysomes after heat stress and reduced translational efficiency (TE) of a subset of stress protective proteins, demonstrating the critical role of translational control early in heat acclimation. Plants carrying the severe hot3-2 allele show decreased TE of auxin-regulated, ribosome-related, and electron transport genes, even under optimal growth conditions. The hot3-2 data suggest that disrupting specific eIF5B interactions on the ribosome can, directly or indirectly, differentially affect translation. Thus, modulating eIF5B interactions could be another mechanism of gene-specific translational control.
Keyphrases
- arabidopsis thaliana
- heat stress
- rna seq
- genome wide
- single cell
- transcription factor
- wild type
- genome wide identification
- copy number
- high temperature
- dna methylation
- early onset
- signaling pathway
- autism spectrum disorder
- stress induced
- drug induced
- big data
- cell free
- deep learning
- circulating tumor cells
- data analysis