Angiogenin-Cleaved tRNA Halves Interact with Cytochrome c, Protecting Cells from Apoptosis during Osmotic Stress

ABSTRACT Adaptation to changes in extracellular tonicity is essential for cell survival. However, severe or chronic hyperosmotic stress induces apoptosis, which involves cytochrome c (Cyt c) release from mitochondria and subsequent apoptosome formation. Here, we show that angiogenin-induced accumulation of tRNA halves (or tiRNAs) is accompanied by increased survival in hyperosmotically stressed mouse embryonic fibroblasts. Treatment of cells with angiogenin inhibits stress-induced formation of the apoptosome and increases the interaction of small RNAs with released Cyt c in a ribonucleoprotein (Cyt c-RNP) complex. Next-generation sequencing of RNA isolated from the Cyt c-RNP complex reveals that 20 tiRNAs are highly enriched in the Cyt c-RNP complex. Preferred components of this complex are 5′ and 3′ tiRNAs of specific isodecoders within a family of isoacceptors. We also demonstrate that Cyt c binds tiRNAs in vitro, and the pool of Cyt c-interacting RNAs binds tighter than individual tiRNAs. Finally, we show that angiogenin treatment of primary cortical neurons exposed to hyperosmotic stress also decreases apoptosis. Our findings reveal a connection between angiogenin-generated tiRNAs and cell survival in response to hyperosmotic stress and suggest a novel cellular complex involving Cyt c and tiRNAs that inhibits apoptosome formation and activity.

[1]  Q. Garrett,et al.  Decrease in hyperosmotic stress–induced corneal epithelial cell apoptosis by L-carnitine , 2013, Molecular vision.

[2]  J. Yong,et al.  tRNA binds to cytochrome c and inhibits caspase activation. , 2010, Molecular cell.

[3]  D. Green,et al.  Mitochondria and cell death: outer membrane permeabilization and beyond , 2010, Nature Reviews Molecular Cell Biology.

[4]  A. Komar,et al.  A Novel Feedback Loop Regulates the Response to Endoplasmic Reticulum Stress via the Cooperation of Cytoplasmic Splicing and mRNA Translation , 2012, Molecular and Cellular Biology.

[5]  Dean P. Jones,et al.  Prevention of Apoptosis by Bcl-2: Release of Cytochrome c from Mitochondria Blocked , 1997, Science.

[6]  Xiongwei Zhu,et al.  eIF2α Phosphorylation Tips the Balance to Apoptosis during Osmotic Stress* , 2010, The Journal of Biological Chemistry.

[7]  J F Riordan,et al.  Crystal structure of human angiogenin reveals the structural basis for its functional divergence from ribonuclease. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[8]  K. Collins,et al.  Starvation-induced Cleavage of the tRNA Anticodon Loop in Tetrahymena thermophila* , 2005, Journal of Biological Chemistry.

[9]  T. Kuwana,et al.  The ‘harmless’ release of cytochrome c , 2000, Cell Death and Differentiation.

[10]  Philippe Marin,et al.  Motoneurons Secrete Angiogenin to Induce RNA Cleavage in Astroglia , 2012, The Journal of Neuroscience.

[11]  N. B. Sepuri,et al.  Perturbation of apoptosis upon binding of tRNA to the heme domain of cytochrome c , 2013, Apoptosis.

[12]  Xiaodong Wang,et al.  Cytochrome c Promotes Caspase-9 Activation by Inducing Nucleotide Binding to Apaf-1* , 2000, The Journal of Biological Chemistry.

[13]  S. Cory,et al.  Apoptosomes: engines for caspase activation. , 2002, Current opinion in cell biology.

[14]  Steven P Gygi,et al.  Angiogenin-induced tRNA fragments inhibit translation initiation. , 2011, Molecular cell.

[15]  A. Stonestrom,et al.  Apoptotic regulation and tRNA , 2010, Protein & Cell.

[16]  K. Ikeda,et al.  Molecular and cellular mechanism of glutamate receptors in relation to amyotrophic lateral sclerosis. , 2002, Current drug targets. CNS and neurological disorders.

[17]  S. Ludtke,et al.  The holo-apoptosome: activation of procaspase-9 and interactions with caspase-3. , 2011, Structure.

[18]  Interaction of cytochrome c with tRNA and other polynucleotides , 2012, Molecular Biology Reports.

[19]  G. Hu,et al.  Angiogenin inhibits nuclear translocation of apoptosis inducing factor in a Bcl‐2‐dependent manner , 2012, Journal of cellular physiology.

[20]  Pavel Ivanov,et al.  Angiogenin-induced tRNA-derived Stress-induced RNAs Promote Stress-induced Stress Granule Assembly* , 2010, The Journal of Biological Chemistry.

[21]  M. Kurokawa,et al.  Inhibition of Apoptosome Formation by Suppression of Hsp90β Phosphorylation in Tyrosine Kinase-Induced Leukemias , 2008, Molecular and Cellular Biology.

[22]  Patricia P. Chan,et al.  GtRNAdb: a database of transfer RNA genes detected in genomic sequence , 2008, Nucleic Acids Res..

[23]  R. Parker,et al.  The RNase Rny1p cleaves tRNAs and promotes cell death during oxidative stress in Saccharomyces cerevisiae , 2009, The Journal of cell biology.

[24]  Xiaodong Wang,et al.  Mitochondrial activation of apoptosis , 2004, Cell.

[25]  D. Newton,et al.  Molecular determinants of apoptosis induced by the cytotoxic ribonuclease onconase: evidence for cytotoxic mechanisms different from inhibition of protein synthesis. , 2000, Cancer research.

[26]  S. Eschenburg,et al.  A molecular view on signal transduction by the apoptosome. , 2012, Cellular signalling.

[27]  R. Parker,et al.  Stressing Out over tRNA Cleavage , 2009, Cell.

[28]  T. Mak,et al.  Apaf1 Is Required for Mitochondrial Pathways of Apoptosis and Brain Development , 1998, Cell.

[29]  G. Mclendon,et al.  Cytochrome c binding to Apaf-1: the effects of dATP and ionic strength. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[30]  V. de Crécy-Lagard,et al.  Biosynthesis and function of posttranscriptional modifications of transfer RNAs. , 2012, Annual review of genetics.

[31]  Tao Pan,et al.  Genome-wide analysis of N1-methyl-adenosine modification in human tRNAs. , 2010, RNA.

[32]  G. Lip,et al.  Angiogenin: a review of the pathophysiology and potential clinical applications , 2006, Journal of thrombosis and haemostasis : JTH.

[33]  O. Hardiman,et al.  Control of Motoneuron Survival by Angiogenin , 2008, The Journal of Neuroscience.

[34]  M. R. Sheen,et al.  How tonicity regulates genes: story of TonEBP transcriptional activator , 2006, Acta physiologica.

[35]  T. Pan,et al.  Genome-wide Identification and Quantitative Analysis of Cleaved tRNA Fragments Induced by Cellular Stress* , 2012, The Journal of Biological Chemistry.

[36]  A. Hopper,et al.  tRNA biology charges to the front. , 2010, Genes & development.

[37]  S. B. Bratton,et al.  Recruitment, activation and retention of caspases‐9 and ‐3 by Apaf‐1 apoptosome and associated XIAP complexes , 2001, The EMBO journal.

[38]  J. Prehn,et al.  Molecular Mechanisms in Amyotrophic Lateral Sclerosis: The Role of Angiogenin, a Secreted RNase , 2012, Front. Neurosci..

[39]  V. de Laurenzi,et al.  Role of Apoptosis in disease , 2012, Aging.

[40]  David R McIlwain,et al.  Caspase functions in cell death and disease. , 2013, Cold Spring Harbor perspectives in biology.

[41]  J. Bujnicki,et al.  MODOMICS: a database of RNA modification pathways—2013 update , 2012, Nucleic Acids Res..

[42]  S. Srinivasula,et al.  Negative regulation of cytochrome c‐mediated oligomerization of Apaf‐1 and activation of procaspase‐9 by heat shock protein 90 , 2000, The EMBO journal.

[43]  G. Hu,et al.  Emerging role of angiogenin in stress response and cell survival under adverse conditions , 2012, Journal of cellular physiology.

[44]  T. Pan,et al.  A Role for tRNA Modifications in Genome Structure and Codon Usage , 2012, Cell.

[45]  B. Chandran,et al.  Angiogenin functionally interacts with p53 and regulates p53 mediated apoptosis and cell survival , 2011, Oncogene.

[46]  T. Pan,et al.  Reversible and Rapid Transfer-RNA Deactivation as a Mechanism of Translational Repression in Stress , 2013, PLoS genetics.

[47]  M. Burg,et al.  Cellular response to hyperosmotic stresses. , 2007, Physiological reviews.

[48]  G. Hu,et al.  Angiogenin prevents serum withdrawal‐induced apoptosis of P19 embryonal carcinoma cells , 2010, The FEBS journal.

[49]  R Y Tsien,et al.  Cytochrome c is released in a single step during apoptosis , 2005, Cell Death and Differentiation.

[50]  Yi Tie,et al.  Stress induces tRNA cleavage by angiogenin in mammalian cells , 2009, FEBS letters.

[51]  Pamela J Green,et al.  tRNA cleavage is a conserved response to oxidative stress in eukaryotes. , 2008, RNA.

[52]  S. Yamasaki,et al.  Angiogenin cleaves tRNA and promotes stress-induced translational repression , 2009, The Journal of cell biology.

[53]  K. Acharya,et al.  Structural and molecular insights into the mechanism of action of human angiogenin-ALS variants in neurons , 2012, Nature Communications.

[54]  X. Liu,et al.  An APAF-1·Cytochrome c Multimeric Complex Is a Functional Apoptosome That Activates Procaspase-9* , 1999, The Journal of Biological Chemistry.

[55]  A. Rowan.  Guide for the Care and Use of Laboratory Animals , 1979 .