Phased Protein Synthesis at Several Circadian Times Does Not Change Protein Levels in Gonyaulax

AbstractSpinal muscular atrophy (SMA) is a neuromuscular disease characterized by loss of lower motor neurons, which leads to proximal muscle weakness and atrophy. SMA is caused by reduced survival motor neuron (SMN) protein levels due to biallelic deletions or mutations in the SMN1 gene. When SMN levels fall under a certain threshold, a plethora of cellular pathways are disturbed, including RNA processing, protein synthesis, metabolic defects, and mitochondrial function. Dysfunctional mitochondria can harm cells by decreased ATP production and increased oxidative stress due to elevated cellular levels of reactive oxygen species (ROS). Since neurons mainly produce energy via mitochondrial oxidative phosphorylation, restoring metabolic/oxidative homeostasis might rescue SMA pathology. Here, we report, based on proteome analysis, that SMA motor neurons show disturbed energy homeostasis due to dysfunction of mitochondrial complex I. This results in a lower basal ATP concentration and higher ROS production that causes an increase of protein carbonylation and impaired protein synthesis in SMA motor neurons. Counteracting these cellular impairments with pyruvate reduces elevated ROS levels, increases ATP and SMN protein levels in SMA motor neurons. Furthermore, we found that pyruvate-mediated SMN protein synthesis is mTOR-dependent. Most importantly, we showed that ROS regulates protein synthesis at the translational initiation step, which is impaired in SMA. As many neuropathies share pathological phenotypes such as dysfunctional mitochondria, excessive ROS, and impaired protein synthesis, our findings suggest new molecular interactions among these pathways. Additionally, counteracting these impairments by reducing ROS and increasing ATP might be beneficial for motor neuron survival in SMA patients.

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The Nuclear Lamina: Protein Accumulation and Disease

Biomedicines ◽

10.3390/biomedicines8070188 ◽

2020 ◽

Vol 8 (7) ◽

pp. 188

Author(s):

Carla Almendáriz-Palacios ◽

Zoe E. Gillespie ◽

Matthew Janzen ◽

Valeria Martinez ◽

Joanna M. Bridger ◽

...

Keyword(s):

Dna Repair ◽

Protein Synthesis ◽

Transcriptional Regulation ◽

Nuclear Envelope ◽

Genome Organization ◽

Nuclear Lamina ◽

Protein Accumulation ◽

Protein Levels ◽

Protein Clearance ◽

Serious Disease

Cellular health is reliant on proteostasis—the maintenance of protein levels regulated through multiple pathways modulating protein synthesis, degradation and clearance. Loss of proteostasis results in serious disease and is associated with aging. One proteinaceous structure underlying the nuclear envelope—the nuclear lamina—coordinates essential processes including DNA repair, genome organization and epigenetic and transcriptional regulation. Loss of proteostasis within the nuclear lamina results in the accumulation of proteins, disrupting these essential functions, either via direct interactions of protein aggregates within the lamina or by altering systems that maintain lamina structure. Here we discuss the links between proteostasis and disease of the nuclear lamina, as well as how manipulating specific proteostatic pathways involved in protein clearance could improve cellular health and prevent/reverse disease.

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Specific post-absorptive and post-prandial responses of protein synthesis to dietary protein levels in muscle, liver and small intestine

Reproduction Nutrition Development ◽

10.1051/rnd:19980208 ◽

1998 ◽

Vol 38 (2) ◽

pp. 188-189

Author(s):

M. A. Arnal ◽

M. C. Valluy ◽

P. Capitan ◽

G. Bayle ◽

P. Patureau Mirand

Keyword(s):

Protein Synthesis ◽

Small Intestine ◽

Dietary Protein ◽

Protein Levels

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Nitrogen balance, microbial protein synthesis and blood metabolites in fattening of male Bali cattle fed ration with different protein levels in smallholder farms

Journal of the Indonesian Tropical Animal Agriculture ◽

10.14710/jitaa.43.1.43-53 ◽

2018 ◽

Vol 43 (1) ◽

pp. 43 ◽

Cited By ~ 1

Author(s):

P. K. Tahuk ◽

S. P. S. Budhi ◽

P. Panjono ◽

E. Baliarti

Keyword(s):

Protein Synthesis ◽

Blood Glucose ◽

Nitrogen Balance ◽

Blood Metabolites ◽

Microbial Protein ◽

Smallholder Farms ◽

Microbial Protein Synthesis ◽

Protein Levels ◽

Before And After ◽

Bali Cattle

Research was aimed to determine nitrogen balance, microbial protein synthesis, and blood metabolites of male Bali cattle fattening fed ration with different protein level in smallholder farms North Central Timor, Province of East Timor Tenggara, Indonesia. The cattle used were 18 heads aged 2 to 2.5 years with initial body weight of 229.86±12.46 kg. The cattle were randomly divided into three treatment groups. The T0 group was given feed the same as traditional fattening cattle practices by farmers,T1 group fed ration containing 12% crude protein (CP) and 72% total digestible nutrients (TDN), andT2 group fedration containing 15% CP and 72%TDN. Cattle were fed individually for 90 days and drinkingwater ad libitum. The data were analyzedby analysis of variance.Results of research indicated the nitrogen balance, and blood urea nitrogen between T1 and T2 were relatively similar, but those were higher (P<0.05) than T0 . In contrast, microbial proteins synthesis, and blood glucose at 0, 4, and 6 hours before and after feeding were relatively similar between the groups. Blood glucose of T2 at 2 hours after intake were higher (P <0.05) than T0, but was not different with T1 . It can be concluded, that the fattening maleBali cattle fed ration containing 12% CP and 72% TDNimprovedthe nitrogen balance and blood metabolites, butit was no positive effect on the microbial proteins and N synthesis.

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Acute Phase Protein Levels and Thymus, Spleen and Plasma Protein Synthesis Rates Differ in Adult and Old Rats

Journal of Nutrition ◽

10.1093/jn/133.1.215 ◽

2003 ◽

Vol 133 (1) ◽

pp. 215-219 ◽

Cited By ~ 25

Author(s):

Isabelle Papet ◽

Dominique Dardevet ◽

Claire Sornet ◽

Fabienne Béchereau ◽

Jacques Prugnaud ◽

...

Keyword(s):

Protein Synthesis ◽

Acute Phase ◽

Plasma Protein ◽

Acute Phase Protein ◽

Protein Levels ◽

Phase Protein ◽

Old Rats

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In vitro Na+, K+-ATPase (EC 3.6.1.3)-dependent respiration and protein synthesis in skeletal muscle of pigs fed at three dietary protein levels

British Journal Of Nutrition ◽

10.1079/bjn19890135 ◽

1989 ◽

Vol 61 (3) ◽

pp. 453-465 ◽

Cited By ~ 14

Author(s):

O. Adeola ◽

L. G. Young ◽

B. W. Mcbride ◽

R. O. Ball

Keyword(s):

Protein Synthesis ◽

Dietary Protein ◽

Protein Concentration ◽

Live Weight ◽

Synthesis Rate ◽

Sartorius Muscle ◽

Close Link ◽

Protein Levels ◽

Daily Gain

1. Eighteen pigs were offered diets containing 130, 170 or 210 g protein/kg with three barrows and three gilts per diet from 20 to 60 kg live weight. Oxygen consumption, Na1, K1-ATPase (EC 3·6·1· 3)-dependent and -independent respiration and protein synthesis were measured in vitro in intercostal and sartorius muscle preparations from these pigs.2. Increasing dietary protein concentration increased (P < 0·01) daily gain and dissectible muscle in carcass.3. O2 consumption and Na+, K+-ATPase-dependent respiration of the intercostal and sartorius muscles increased linearly (P < 0·01) with increase in dietary protein concentration. The requirement for the support of the transport of Na+ and K+ across the cell membrane in these muscles, on average, accounted for 22–25% of the O2 consumption.4. Synthesis rate (mg/g per d) of protein in the sartorius muscle increased (P < 0·05) from 3·05 to 5·07 and increased (P < 0·1) from 2·57 to 4.06 in the intercostal muscle as dietary protein increased from 130 to 210 g/kg diet.5. Regression of Na+, K+-ATPase-dependent respiration against protein synthesis in each of intercostal and sartorius muscles showed a linear relation, an attestation of a close link between productive processes and auxiliary energy expenditure.

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Neuroprotective Action of Cycloheximide Involves Induction of Bcl-2 and Antioxidant Pathways

The Journal of Cell Biology ◽

10.1083/jcb.136.5.1137 ◽

1997 ◽

Vol 136 (5) ◽

pp. 1137-1149 ◽

Cited By ~ 91

Author(s):

Katsutoshi Furukawa ◽

Steven Estus ◽

Weiming Fu ◽

Robert J. Mark ◽

Mark P. Mattson

Keyword(s):

Superoxide Dismutase ◽

Protein Synthesis ◽

Antioxidant Enzymes ◽

Neurotrophic Factors ◽

Death Process ◽

Antisense Oligodeoxynucleotide ◽

Protein Synthesis Inhibitor ◽

Gene Products ◽

Protein Levels ◽

Neuroprotective Action

The ability of the protein synthesis inhibitor cycloheximide (CHX) to prevent neuronal death in different paradigms has been interpreted to indicate that the cell death process requires synthesis of “killer” proteins. On the other hand, data indicate that neurotrophic factors protect neurons in the same death paradigms by inducing expression of neuroprotective gene products. We now provide evidence that in embryonic rat hippocampal cell cultures, CHX protects neurons against oxidative insults by a mechanism involving induction of neuroprotective gene products including the antiapoptotic gene bcl-2 and antioxidant enzymes. Neuronal survival after exposure to glutamate, FeSO4, and amyloid β-peptide was increased in cultures pretreated with CHX at concentrations of 50–500 nM; higher and lower concentrations were ineffective. Neuroprotective concentrations of CHX caused only a moderate (20–40%) reduction in overall protein synthesis, and induced an increase in c-fos, c-jun, and bcl-2 mRNAs and protein levels as determined by reverse transcription–PCR analysis and immunocytochemistry, respectively. At neuroprotective CHX concentrations, levels of c-fos heteronuclear RNA increased in parallel with c-fos mRNA, indicating that CHX acts by inducing transcription. Neuroprotective concentrations of CHX suppressed accumulation of H2O2 induced by FeSO4, suggesting activation of antioxidant pathways. Treatment of cultures with an antisense oligodeoxynucleotide directed against bcl-2 mRNA decreased Bcl-2 protein levels and significantly reduced the neuroprotective action of CHX, suggesting that induction of Bcl-2 expression was mechanistically involved in the neuroprotective actions of CHX. In addition, activity levels of the antioxidant enzymes Cu/ Zn-superoxide dismutase, Mn-superoxide dismutase, and catalase were significantly increased in cultures exposed to neuroprotective levels of CHX. Our data suggest that low concentrations of CHX can promote neuron survival by inducing increased levels of gene products that function in antioxidant pathways, a neuroprotective mechanism similar to that used by neurotrophic factors.

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Gain-of-function genetic screen of the kinome reveals BRSK2 as an inhibitor of the NRF2 transcription factor

10.1101/832279 ◽

2019 ◽

Cited By ~ 1

Author(s):

Tigist Y Tamir ◽

Brittany M Bowman ◽

Megan J Agajanian ◽

Dennis Goldfarb ◽

Travis P Schrank ◽

...

Keyword(s):

Transcription Factor ◽

Protein Synthesis ◽

Human Cancer ◽

Genetic Screen ◽

Mtor Signaling ◽

Negative Regulator ◽

Dependent Manner ◽

Gain Of Function ◽

Protein Levels ◽

Nrf2 Protein

AbstractNFE2L2/NRF2 is a transcription factor and master regulator of cellular antioxidant response. Aberrantly high NRF2-dependent transcription is recurrent in human cancer, and conversely NRF2 protein levels as well as activity is diminished with age and in neurodegenerative disorders. Though NRF2 activating drugs are clinically beneficial, NRF2 inhibitors do not yet exist. Here we used a gain-of-function genetic screen of the kinome to identify new druggable regulators of NRF2 signaling. We found that the understudied protein kinase Brain Specific Kinase 2 (BRSK2) and the related BRSK1 kinases suppress NRF2-dependent transcription and NRF2 protein levels in an activity-dependent manner. Integrated phosphoproteomics and RNAseq studies revealed that BRSK2 drives AMPK activation and suppresses mTOR signaling. As a result, BRSK2 kinase activation suppressed ribosome-RNA complexes, global protein synthesis, and NRF2 protein levels. Collectively, our data establish the catalytically active BRSK2 kinase as a negative regulator of NRF2 via the AMPK/mTOR signaling. This signaling axis may prove useful for therapeutically targeting NRF2 in human diseases.Summary StatementBRSK2 suppresses NRF2 signaling by inhibiting protein synthesis through mTOR downregulation.

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Nestin upregulation characterizes vascular remodeling secondary to hypertension in the rat

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00804.2014 ◽

2015 ◽

Vol 308 (10) ◽

pp. H1265-H1274 ◽

Cited By ~ 8

Author(s):

Kim Tardif ◽

Vanessa Hertig ◽

Natacha Duquette ◽

Louis Villeneuve ◽

Ismail El-Hamamsy ◽

...

Keyword(s):

Protein Synthesis ◽

Smooth Muscle ◽

Carotid Artery ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Protein Levels ◽

Vessel Remodeling ◽

Peptide Growth Factor

Proliferation and hypertrophy of vascular smooth muscle cells represent hallmark features of vessel remodeling secondary to hypertension. The intermediate filament protein nestin was recently identified in vascular smooth muscle cells and in other cell types directly participated in proliferation. The present study tested the hypothesis that vessel remodeling secondary to hypertension was characterized by nestin upregulation in vascular smooth muscle cells. Two weeks after suprarenal abdominal aorta constriction of adult male Sprague-Dawley rats, elevated mean arterial pressure increased the media area and thickness of the carotid artery and aorta and concomitantly upregulated nestin protein levels. In the normal adult rat carotid artery, nestin immunoreactivity was observed in a subpopulation of vascular smooth muscle cells, and the density significantly increased following suprarenal abdominal aorta constriction. Filamentous nestin was detected in cultured rat carotid artery- and aorta-derived vascular smooth muscle cells and an analogous paradigm observed in human aorta-derived vascular smooth muscle cells. ANG II and EGF treatment of vascular smooth muscle cells stimulated DNA and protein synthesis and increased nestin protein levels. Lentiviral short-hairpin RNA-mediated nestin depletion of carotid artery-derived vascular smooth muscle cells inhibited peptide growth factor-stimulated DNA synthesis, whereas protein synthesis remained intact. These data have demonstrated that vessel remodeling secondary to hypertension was characterized in part by nestin upregulation in vascular smooth muscle cells. The selective role of nestin in peptide growth factor-stimulated DNA synthesis has revealed that the proliferative and hypertrophic responses of vascular smooth muscle cells were mediated by divergent signaling events.

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Apoptosis Triggered by Myc-Induced Suppression of Bcl-XL or Bcl-2 Is Bypassed during Lymphomagenesis

Molecular and Cellular Biology ◽

10.1128/mcb.21.15.5063-5070.2001 ◽

2001 ◽

Vol 21 (15) ◽

pp. 5063-5070 ◽

Cited By ~ 135

Author(s):

Christine M. Eischen ◽

David Woo ◽

Martine F. Roussel ◽

John L. Cleveland

Keyword(s):

Protein Synthesis ◽

Transgenic Mice ◽

Tumor Cells ◽

De Novo ◽

Apoptotic Pathway ◽

Antiapoptotic Protein ◽

Protein Levels ◽

Apoptotic Pathways ◽

Induced Apoptosis ◽

De Novo Protein Synthesis

ABSTRACT Enforced Bcl-2 expression inhibits Myc-induced apoptosis and cooperates with Myc in transformation. Here we report that the synergy between Bcl-2 and Myc in transforming hematopoietic cells in fact reflects a Myc-induced pathway that selectively suppresses the expression of the Bcl-XL or Bcl-2 antiapoptotic protein. Myc activation suppresses Bcl-XL RNA and protein levels in cultures of primary myeloid and lymphoid progenitors, and Bcl-XL and Bcl-2 expression is inhibited by Myc in precancerous B cells from Eμ-myc transgenic mice. The suppression of bcl-X RNA levels by Myc requires de novo protein synthesis, indicating that repression is indirect. Importantly, the suppression of Bcl-2 or Bcl-XL by Myc is corrupted during Myc-induced tumorigenesis, as Bcl-2 and/or Bcl-XLlevels are markedly elevated in over one-half of all lymphomas arising in Eμ-myc transgenic mice. Bcl-2 and/or Bcl-XL overexpression did not correlate with loss of ARF or p53 function in tumor cells, indicating that these two apoptotic pathways are inactivated independently. Therefore, the suppression of Bcl-XL or Bcl-2 expression represents a physiological Myc-induced apoptotic pathway that is frequently bypassed during lymphomagenesis.

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