S R Kimball


Affiliation: Pennsylvania State University
Country: USA


  1. Kimball S, Lang C. Mechanisms Underlying Muscle Protein Imbalance Induced by Alcohol. Annu Rev Nutr. 2018;38:197-217 pubmed publisher
    ..Further studies are necessary to define the relative contributions of these bidirectional changes in protein synthesis and autophagy in the etiology of alcoholic myopathy in skeletal muscle and the heart. ..
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    Kimball S, Orellana R, O Connor P, Suryawan A, Bush J, Nguyen H, et al. Endotoxin induces differential regulation of mTOR-dependent signaling in skeletal muscle and liver of neonatal pigs. Am J Physiol Endocrinol Metab. 2003;285:E637-44 pubmed
    ..This finding suggests that the initiator methionyl-tRNA-rather than the mRNA-binding step in translation initiation may play a more critical role in maintaining protein synthesis rates in the neonate during sepsis. ..
  3. Ravi S, Schilder R, Kimball S. Role of precursor mRNA splicing in nutrient-induced alterations in gene expression and metabolism. J Nutr. 2015;145:841-6 pubmed publisher
    ..The goal of this review is to highlight selected recent advances in our understanding of the regulation of pre-mRNA splicing by nutrients and modulation of nutrient metabolism that result from changes in pre-mRNA splicing. ..
  4. Kelleher A, Pereira S, Jefferson L, Kimball S. REDD2 expression in rat skeletal muscle correlates with nutrient-induced activation of mTORC1: responses to aging, immobilization, and remobilization. Am J Physiol Endocrinol Metab. 2015;308:E122-9 pubmed publisher
    ..In conclusion, changes in mTORC1 signaling associated with aging, immobilization, and remobilization were inversely proportional to alterations in REDD2 mRNA expression. ..
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    Kimball S. Regulation of global and specific mRNA translation by amino acids. J Nutr. 2002;132:883-6 pubmed
    ..Thus, deprivation of essential amino acids not only directly and rapidly represses global mRNA translation, but also potentially results in a reduction in the capacity to synthesize protein. ..
  6. Kimball S, Jefferson L. Control of translation initiation through integration of signals generated by hormones, nutrients, and exercise. J Biol Chem. 2010;285:29027-32 pubmed publisher
    ..Together, modulation of these two regulatory steps in translation initiation accounts in large part for changes in protein synthesis in skeletal muscle produced by the integration of inputs from hormones, nutrients, and exercise. ..
  7. Gordon B, Steiner J, Lang C, Jefferson L, Kimball S. Reduced REDD1 expression contributes to activation of mTORC1 following electrically induced muscle contraction. Am J Physiol Endocrinol Metab. 2014;307:E703-11 pubmed publisher
    ..Overall, the data demonstrate that REDD1 expression contributes to the modulation of mTORC1 signaling following feeding- and contraction-induced activation of the pathway. ..
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    Kimball S, Shantz L, Horetsky R, Jefferson L. Leucine regulates translation of specific mRNAs in L6 myoblasts through mTOR-mediated changes in availability of eIF4E and phosphorylation of ribosomal protein S6. J Biol Chem. 1999;274:11647-52 pubmed
    ..Thus, leucine acting through an mTOR-dependent pathway stimulates the translation of specific mRNAs both by increasing the availability of eIF4E and by stimulating phosphorylation of S6. ..
  9. Kimball S, Gordon B, Moyer J, Dennis M, Jefferson L. Leucine induced dephosphorylation of Sestrin2 promotes mTORC1 activation. Cell Signal. 2016;28:896-906 pubmed publisher
    ..Overall, the results support a model in which leucine selectively promotes dephosphorylation of Sestrin2, causing it to dissociate from and thereby activate GATOR2, leading to activation of mTORC1. ..

More Information


  1. Kimball S, Ravi S, Gordon B, Dennis M, Jefferson L. Amino Acid-Induced Activation of mTORC1 in Rat Liver Is Attenuated by Short-Term Consumption of a High-Fat Diet. J Nutr. 2015;145:2496-502 pubmed publisher
  2. Gordon B, Williamson D, Lang C, Jefferson L, Kimball S. Nutrient-induced stimulation of protein synthesis in mouse skeletal muscle is limited by the mTORC1 repressor REDD1. J Nutr. 2015;145:708-13 pubmed publisher
  3. Dennis M, Coleman C, Berg A, Jefferson L, Kimball S. REDD1 enhances protein phosphatase 2A-mediated dephosphorylation of Akt to repress mTORC1 signaling. Sci Signal. 2014;7:ra68 pubmed publisher
    ..Overall, the results demonstrate that REDD1 acts not only as a repressor of mTORC1 but also as a constant modulator of the phosphorylation of Akt in response to growth factors and nutrients. ..
  4. Martin T, Dennis M, Gordon B, Kimball S, Jefferson L. mTORC1 and JNK coordinate phosphorylation of the p70S6K1 autoinhibitory domain in skeletal muscle following functional overloading. Am J Physiol Endocrinol Metab. 2014;306:E1397-405 pubmed publisher
    ..Overall, the results provide evidence that the mTORC1 and JNK signaling pathways coordinate the site-specific phosphorylation of p70S6K1. They also identify a novel role for mTORC1 and mTORC2 in the inhibition of JNK. ..
  5. Kimball S, Jefferson L. Induction of REDD1 gene expression in the liver in response to endoplasmic reticulum stress is mediated through a PERK, eIF2? phosphorylation, ATF4-dependent cascade. Biochem Biophys Res Commun. 2012;427:485-9 pubmed publisher
    ..Moreover, the induction of REDD1 gene expression was shown to require the protein kinase PERK and enhanced phosphorylation of its substrate, the ?-subunit of eukaryotic initiation factor 2. ..
  6. Kimball S, Do A, Kutzler L, Cavener D, Jefferson L. Rapid turnover of the mTOR complex 1 (mTORC1) repressor REDD1 and activation of mTORC1 signaling following inhibition of protein synthesis. J Biol Chem. 2008;283:3465-75 pubmed
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    Kimball S, Siegfried B, Jefferson L. Glucagon represses signaling through the mammalian target of rapamycin in rat liver by activating AMP-activated protein kinase. J Biol Chem. 2004;279:54103-9 pubmed
    ..Amino acids also enhance AMPK phosphorylation, although to a lesser extent than glucagon and amino acids combined. ..
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    Kimball S, Fabian J, Pavitt G, Hinnebusch A, Jefferson L. Regulation of guanine nucleotide exchange through phosphorylation of eukaryotic initiation factor eIF2alpha. Role of the alpha- and delta-subunits of eiF2b. J Biol Chem. 1998;273:12841-5 pubmed
    ..The results provide the first direct biochemical evidence that the alpha- and delta-subunits of eIF2B are involved in mediating the effect of substrate phosphorylation. ..
  9. Kimball S, Abbas A, Jefferson L. Melatonin represses oxidative stress-induced activation of the MAP kinase and mTOR signaling pathways in H4IIE hepatoma cells through inhibition of Ras. J Pineal Res. 2008;44:379-86 pubmed publisher
    ..Overall, the results suggest that melatonin acts to prevent many of the H(2)O(2)-induced alterations in the MAPK and mTOR signaling pathways through inhibition of Ras, at least in H4IIE hepatoma cells. ..
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    Kimball S, Horetsky R, Ron D, Jefferson L, Harding H. Mammalian stress granules represent sites of accumulation of stalled translation initiation complexes. Am J Physiol Cell Physiol. 2003;284:C273-84 pubmed
    ..Finally, we also show that stress granules contain many, if not all, of the components of the 48S preinitiation complex, but not 60S ribosomal subunits, suggesting that they represent stalled translation initiation complexes. ..
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    Kimball S, Jefferson L, Nguyen H, Suryawan A, Bush J, Davis T. Feeding stimulates protein synthesis in muscle and liver of neonatal pigs through an mTOR-dependent process. Am J Physiol Endocrinol Metab. 2000;279:E1080-7 pubmed
    ..However, in skeletal muscle, these two processes may account for only part of the stimulation of protein synthesis, and thus additional steps may be involved in the response...