1
|
Kim KQ, Nanjaraj Urs AN, Lasehinde V, Greenlaw AC, Hudson BH, Zaher HS. eIF4F complex dynamics are important for the activation of the integrated stress response. Mol Cell 2024; 84:2135-2151.e7. [PMID: 38848692 PMCID: PMC11189614 DOI: 10.1016/j.molcel.2024.04.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 12/08/2023] [Accepted: 04/19/2024] [Indexed: 06/09/2024]
Abstract
In response to stress, eukaryotes activate the integrated stress response (ISR) via phosphorylation of eIF2α to promote the translation of pro-survival effector genes, such as GCN4 in yeast. Complementing the ISR is the target of rapamycin (TOR) pathway, which regulates eIF4E function. Here, we probe translational control in the absence of eIF4E in Saccharomyces cerevisiae. Intriguingly, we find that loss of eIF4E leads to de-repression of GCN4 translation. In addition, we find that de-repression of GCN4 translation is accompanied by neither eIF2α phosphorylation nor reduction in initiator ternary complex (TC). Our data suggest that when eIF4E levels are depleted, GCN4 translation is de-repressed via a unique mechanism that may involve faster scanning by the small ribosome subunit due to increased local concentration of eIF4A. Overall, our findings suggest that relative levels of eIF4F components are key to ribosome dynamics and may play important roles in translational control of gene expression.
Collapse
Affiliation(s)
- Kyusik Q Kim
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | | | - Victor Lasehinde
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Alison C Greenlaw
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Benjamin H Hudson
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Hani S Zaher
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA.
| |
Collapse
|
2
|
Bagheri A, Astafev A, Al-Hashimy T, Jiang P. Tracing Translational Footprint by Ribo-Seq: Principle, Workflow, and Applications to Understand the Mechanism of Human Diseases. Cells 2022; 11:cells11192966. [PMID: 36230928 PMCID: PMC9562884 DOI: 10.3390/cells11192966] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/02/2022] [Accepted: 09/19/2022] [Indexed: 11/30/2022] Open
Abstract
RNA-seq has been widely used as a high-throughput method to characterize transcript dynamic changes in a broad context, such as development and diseases. However, whether RNA-seq-estimated transcriptional dynamics can be translated into protein level changes is largely unknown. Ribo-seq (Ribosome profiling) is an emerging technology that allows for the investigation of the translational footprint via profiling ribosome-bounded mRNA fragments. Ribo-seq coupled with RNA-seq will allow us to understand the transcriptional and translational control of the fundamental biological process and human diseases. This review focuses on discussing the principle, workflow, and applications of Ribo-seq to study human diseases.
Collapse
Affiliation(s)
- Atefeh Bagheri
- Department of Biological, Geological and Environmental Sciences (BGES), Cleveland State University, Cleveland, OH 44115, USA
- Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, Cleveland, OH 44115, USA
| | - Artem Astafev
- Department of Biological, Geological and Environmental Sciences (BGES), Cleveland State University, Cleveland, OH 44115, USA
- Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, Cleveland, OH 44115, USA
| | - Tara Al-Hashimy
- Department of Biological, Geological and Environmental Sciences (BGES), Cleveland State University, Cleveland, OH 44115, USA
| | - Peng Jiang
- Department of Biological, Geological and Environmental Sciences (BGES), Cleveland State University, Cleveland, OH 44115, USA
- Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, Cleveland, OH 44115, USA
- Center for Applied Data Analysis and Modeling (ADAM), Cleveland State University, Cleveland, OH 44115, USA
- Center for RNA Science and Therapeutics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
- Correspondence: ; Tel.: +1-(216)-687-3917
| |
Collapse
|
3
|
Song B, Jiang M, Gao L. RiboNT: A Noise-Tolerant Predictor of Open Reading Frames from Ribosome-Protected Footprints. Life (Basel) 2021; 11:life11070701. [PMID: 34357073 PMCID: PMC8307163 DOI: 10.3390/life11070701] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 01/27/2023] Open
Abstract
Ribo-seq, also known as ribosome profiling, refers to the sequencing of ribosome-protected mRNA fragments (RPFs). This technique has greatly advanced our understanding of translation and facilitated the identification of novel open reading frames (ORFs) within untranslated regions or non-coding sequences as well as the identification of non-canonical start codons. However, the widespread application of Ribo-seq has been hindered because obtaining periodic RPFs requires a highly optimized protocol, which may be difficult to achieve, particularly in non-model organisms. Furthermore, the periodic RPFs are too short (28 nt) for accurate mapping to polyploid genomes, but longer RPFs are usually produced with a compromise in periodicity. Here we present RiboNT, a noise-tolerant ORF predictor that can utilize RPFs with poor periodicity. It evaluates RPF periodicity and automatically weighs the support from RPFs and codon usage before combining their contributions to identify translated ORFs. The results demonstrate the utility of RiboNT for identifying both long and small ORFs using RPFs with either good or poor periodicity. We implemented the pipeline on a dataset of RPFs with poor periodicity derived from membrane-bound polysomes of Arabidopsis thaliana seedlings and identified several small ORFs (sORFs) evolutionarily conserved in diverse plant species. RiboNT should greatly broaden the application of Ribo-seq by minimizing the requirement of RPF quality and allowing the use of longer RPFs, which is critical for organisms with complex genomes because these RPFs can be more accurately mapped to the position from which they were derived.
Collapse
Affiliation(s)
- Bo Song
- Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China;
- Correspondence: (B.S.); (L.G.)
| | - Mengyun Jiang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China;
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China
- Shenzhen Research Institute of Henan University, Shenzhen 518000, China
| | - Lei Gao
- Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
- Correspondence: (B.S.); (L.G.)
| |
Collapse
|