scholarly journals Transcription coordinates histone amounts and genome content

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kora-Lee Claude ◽  
Daniela Bureik ◽  
Dimitra Chatzitheodoridou ◽  
Petia Adarska ◽  
Abhyudai Singh ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Cell Volume ◽  
Genomic Dna ◽  
Intrinsic Property ◽  
Transcript Level ◽  
Cellular Structures ◽  
Feedback Mechanisms ◽  
Global Trend ◽  
Genome Content ◽  
Direct Feedback

AbstractBiochemical reactions typically depend on the concentrations of the molecules involved, and cell survival therefore critically depends on the concentration of proteins. To maintain constant protein concentrations during cell growth, global mRNA and protein synthesis rates are tightly linked to cell volume. While such regulation is appropriate for most proteins, certain cellular structures do not scale with cell volume. The most striking example of this is the genomic DNA, which doubles during the cell cycle and increases with ploidy, but is independent of cell volume. Here, we show that the amount of histone proteins is coupled to the DNA content, even though mRNA and protein synthesis globally increase with cell volume. As a consequence, and in contrast to the global trend, histone concentrations decrease with cell volume but increase with ploidy. We find that this distinct coordination of histone homeostasis and genome content is already achieved at the transcript level, and is an intrinsic property of histone promoters that does not require direct feedback mechanisms. Mathematical modeling and histone promoter truncations reveal a simple and generalizable mechanism to control the cell volume- and ploidy-dependence of a given gene through the balance of the initiation and elongation rates.

scholarly journals Transcription coordinates histone amounts and genome content

2020 ◽  
Author(s):  
Kora-Lee Claude ◽  
Daniela Bureik ◽  
Petia Adarska ◽  
Abhyudai Singh ◽  
Kurt M. Schmoller
Keyword(s):  
Protein Synthesis ◽  
Cell Volume ◽  
Intrinsic Property ◽  
Transcript Level ◽  
Cellular Structures ◽  
Feedback Mechanisms ◽  
Global Trend ◽  
Genome Content ◽  
Direct Feedback ◽  
Volume Decrease

AbstractBiochemical reactions typically depend on the concentrations of the molecules involved, and cell survival therefore critically depends on the concentration of proteins. To maintain constant protein concentrations during cell growth, global mRNA and protein synthesis rates are tightly linked to cell volume. While such regulation is appropriate for most proteins, certain cellular structures do not scale with cell volume. The most striking example of this is the genomic DNA, which doubles during the cell cycle and increases with ploidy, but is independent of cell volume.Here, we show that the amount of histone proteins is coupled to the DNA content, even though mRNA and protein synthesis globally increase with cell volume. As a consequence, and in contrast to the global trend, histone concentrations (i.e. amounts per volume) decrease with cell volume but increase with ploidy. We find that this distinct coordination of histone homeostasis and genome content is already achieved at the transcript level, and is an intrinsic property of histone promoters that does not require direct feedback mechanisms. Mathematical modelling and histone promoter truncations reveal a simple and generalizable mechanism to control the cell volume- and ploidy-dependence of a given gene through the balance of the initiation and elongation rates.

GmNiR-1, a soybean nitrite reductase gene that is regulated by nitrate and light

2001 ◽  
Vol 28 (10) ◽  
pp. 1031
Author(s):  
Chang-Hoon Kim ◽  
Sung-Soo Jun ◽  
Young-Nam Hong
Keyword(s):  
Nitrite Reductase ◽  
Genomic Dna ◽  
Transit Peptide ◽  
Transcript Level ◽  
Simultaneous Treatment ◽  
Reading Frame ◽  
Soybean Seedlings ◽  
Etiolated Seedlings ◽  
Nitrite Reductase Gene ◽  
The Difference

A genomic DNA clone encoding nitrite reductase (NiR; EC 1.7.7.1), GmNiR-1, was isolated from soybean [Glycine max (L.) Merr.]. It is composed of four exons and three introns carrying an open reading frame coding for a protein of 596 amino acids. The putative MW of GmNiR-1 is 67 kDa with theoretical pI of 6.95, but the measured MW is ca 64 kDa. The difference between putative and measured MW of GmNiR-1 lies in the presence of a transit peptide. Genomic DNA blot analysis suggested that soybean NiR gene family consisted of at least three genes. In 2-week-old plants grown in the nitrate-supplemented soil, GmNiR-1 was expressed in roots and leaves, but not in hypocotyls. Transcript level of GmNiR-1 in roots was not increased by light, but was increased by nitrate even in the dark. However, light and nitrate had a synergistic effect on the increased expression of GmNiR-1. A polyclonal antibody generated against the C-terminal of GmNiR-1 hybridized to a single (62 kDa), double (62 and 64 kDa), and three bands (62, 64 and 66 kDa) in roots, hypocotyls and leaves, respectively. In etiolated seedlings, NiR proteins in roots and hypocotyls were induced by simultaneous treatment with light and nitrate, but those in cotyledons were already present substantially without induction, implying the presence of at least two kinds of NiR genes (a constitutive one and an inducible one regulated by light and nitrate) in soybean seedlings.

scholarly journals Altered heat-lability of a fraction of glutathione reductase in aging human lens

1973 ◽  
Vol 134 (4) ◽  
pp. 995-1000 ◽  
Author(s):  
John J. Harding
Keyword(s):  
Protein Synthesis ◽  
Glutathione Reductase ◽  
Phosphoglycerate Kinase ◽  
Intrinsic Property ◽  
Human Lens ◽  
The Core ◽  
Labile Fraction ◽  
Heat Labile ◽  
Glucose 6 Phosphate Dehydrogenase

An unusually heat-labile fraction of glutathione reductase appears in human lens at about an age of 32 years. No such change was found in glucose 6-phosphate dehydrogenase nor in 3-phosphoglycerate kinase. The change is an intrinsic property of glutathione reductase. A greater proportion of the altered glutathione reductase was found in the core, the older part, of the lens. No evidence of a second band of activity was obtained after electrophoresis. Possible interpretations of the results, including errors of protein synthesis, production of a new isoenzyme and post-synthetic changes, are discussed.

Effects of Chloramphenicol on Growth, Size Distribution, Chlorophyll Synthesis and Ultrastructure of Euglena Gracilis

1969 ◽  
Vol 4 (3) ◽  
pp. 627-644
Author(s):  
Y. BEN-SHAUL ◽  
Y. MARKUS
Keyword(s):  
Protein Synthesis ◽  
Cell Division ◽  
Cell Volume ◽  
Chlorophyll Synthesis ◽  
Secondary Effect ◽  
Mean Cell Volume ◽  
Initial Rise ◽  
Dividing Cells ◽  
Light Inhibition ◽  
The Mean

Multiplication of Euglena cells treated by 0.5-1.0 mg/ml chloramphenicol was not disturbed for the first 36 h and inhibition appeared only at later stages. The mean cell volume of treated dividing cells was decreased, although the initial rise in cell volume, which normally occurred during the first 12 h of incubation, was not prevented. The antibiotic also lowered the chlorophyll content of green dividing cells. In dard-grown cells transferred to light, inhibition of chlorophyll synthesis was immediate but not complete, and was followed by a decreased rate of plastid elongation and thylakoid formation. Our findings suggest that chloramphenicol does not cause the loss of existing pigment and that impaired chlorophyll synthesis is a secondary effect of inhibition of protein synthesis. The results also indicate that the greening process is more sensitive than cell division to the antibiotic.

scholarly journals Oxidative stress contributes to the enhanced expression of Gqα/PLCβ1 proteins and hypertrophy of VSMC from SHR: role of growth factor receptor transactivation

2016 ◽  
Vol 310 (5) ◽  
pp. H608-H618 ◽  
Author(s):  
Mohammed Emehdi Atef ◽  
Madhu B. Anand-Srivastava
Keyword(s):  
Oxidative Stress ◽  
Protein Synthesis ◽  
Growth Factor ◽  
Cell Volume ◽  
Growth Factor Receptor ◽  
Mapk Signaling ◽  
Confocal Imaging ◽  
Leucine Incorporation ◽  
Enhanced Expression

We showed previously that vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHRs) exhibit overexpression of Gqα/PLCβ1 proteins, which contribute to increased protein synthesis through the activation of MAP kinase signaling. Because oxidative stress has been shown to be increased in hypertension, the present study was undertaken to examine the role of oxidative stress and underlying mechanisms in enhanced expression of Gqα/PLCβ1 proteins and VSMC hypertrophy. Protein expression was determined by Western blotting, whereas protein synthesis and cell volume, markers for VSMC hypertrophy, were determined by [3H]-leucine incorporation and three-dimensional confocal imaging, respectively. The increased expression of Gqα/PLCβ1 proteins, increased protein synthesis, and augmented cell volume exhibited by VSMCs from SHRs were significantly attenuated by antioxidants N-acetyl-cysteine (NAC), a scavenger of superoxide anion, DPI, an inhibitor of NAD(P)H oxidase. In addition, PP2, AG1024, AG1478, and AG1295, inhibitors of c-Src, insulin-like growth factor receptor (IGFR), epidermal growth factor receptor (EGFR), and platelet-derived growth factor receptor (PDGFR), respectively, also attenuated the enhanced expression of Gqα/PLCβ1 proteins and enhanced protein synthesis in VSMCs from SHRs toward control levels. Furthermore, the levels of IGF-1R and EGFR proteins and not of PDGFR were also enhanced in VSMCs from SHRs, which were attenuated significantly by NAC, DPI, and PP2. In addition, NAC, DPI, and PP2 also attenuated the enhanced phosphorylation of IGF-1R, PDGFR, EGFR, c-Src, and EKR1/2 in VSMCs from SHRs. These data suggest that enhanced oxidative stress in VSMCs from SHRs activates c-Src, which through the transactivation of growth factor receptors and MAPK signaling contributes to enhanced expression of Gqα/PLCβ1 proteins and resultant VSMC hypertrophy.

scholarly journals Long-lived crowded-litter mice have an age-dependent increase in protein synthesis to DNA synthesis ratio and mTORC1 substrate phosphorylation

2014 ◽  
Vol 307 (9) ◽  
pp. E813-E821 ◽  
Author(s):  
Joshua C. Drake ◽  
Danielle R. Bruns ◽  
Frederick F. Peelor ◽  
Laurie M. Biela ◽  
Richard A. Miller ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Dna Synthesis ◽  
Litter Size ◽  
Cellular Structures ◽  
Mtorc1 Signaling ◽  
Age Dependent ◽  
Model Protein ◽  
Substrate Phosphorylation ◽  
Mtor Complex 1 ◽  
New Protein

Increasing mouse litter size [crowded litter (CL)] presumably imposes a transient nutrient stress during suckling and extends lifespan through unknown mechanisms. Chronic calorically restricted and rapamycin-treated mice have decreased DNA synthesis and mTOR complex 1 (mTORC1) signaling but maintained protein synthesis, suggesting maintenance of existing cellular structures. We hypothesized that CL would exhibit similar synthetic and signaling responses to other long-lived models and, by comparing synthesis of new protein to new DNA, that insight may be gained into the potential preservation of existing cellular structures in the CL model. Protein and DNA synthesis was assessed in gastroc complex, heart, and liver of 4- and 7-mo CL mice. We also examined mTORC1 signaling in 3- and 7-mo aged animals. Compared with controls, 4-mo CL had greater DNA synthesis in gastroc complex with no differences in protein synthesis or mTORC1 substrate phosphorylation across tissues. Seven-month CL had less DNA synthesis than controls in heart and greater protein synthesis and mTORC1 substrate phosphorylation across tissues. The increased new protein-to-new DNA synthesis ratio suggests that new proteins are synthesized more so in existing cells at 7 mo, differing from 4 mo, in CL vs. controls. We propose that, in CL, protein synthesis shifts from being directed toward new cells (4 mo) to maintenance of existing cellular structures (7 mo), independently of decreased mTORC1.

scholarly journals Identification of a brain-specific protein kinase Cζ pseudogene (ΨPKCζ) transcript

1995 ◽  
Vol 310 (3) ◽  
pp. 835-843 ◽  
Author(s):  
J E Andrea ◽  
M P Walsh
Keyword(s):  
Protein Synthesis ◽  
Protein Kinase ◽  
Blot Analysis ◽  
Genomic Dna ◽  
Stop Codon ◽  
Pcr Analysis ◽  
Translation System ◽  
Western Blots ◽  
Rnase Protection ◽  
Pkc Zeta

Protein kinase C (PKC), a widely-distributed enzyme implicated in the regulation of many physiological processes, consists of a family of at least twelve isoenzymes which differ in tissue distribution, subcellular localization, regulatory properties, etc. In addition to this heterogeneity at the protein level, we identify here for the first time a PKC zeta pseudogene (psi PKC zeta) transcript, specifically expressed in the brain, which is identical with PKC zeta except for sequence divergence within the first variable domain (V1). The authenticity of this unique V1 sequence (V1′) in mRNA was confirmed by RNase protection and reverse transcriptase PCR (RT-PCR) analysis. When translated in-frame with PKC zeta, a stop codon is located 28 amino acids towards the N-terminus of the divergence point and the intervening sequence lacks an expected initiating methionine. psi PKC zeta is non-functional in terms of protein synthesis since Western blotting with an antibody directed against the C-terminus of PKC zeta failed to reveal a protein smaller than PKC zeta, and synthetic psi PKC zeta RNA failed to support protein synthesis in a translation system in vitro. PCR amplification of rat genomic DNA demonstrated lack of an intron at the junction between V1′ and the first constant domain (the V1′-C1 border), and genomic DNA Southern blot analysis using PKC zeta and psi PKC zeta-specific probes indicated that they have different loci. psi PKC zeta, therefore, is not derived from the PKC zeta gene by alternative splicing, but rather is the product of a distinct gene. In Northern blot analysis, brain PKC zeta mRNA was identified as a low-abundance 3.1 kb transcript, while the abundant 2.5 and 4.7 kb mRNAs previously reported to encode PKC zeta are, in fact, psi PKC zeta transcripts. Analysis of rat brain, heart, lung, liver, kidney and skeletal muscle revealed psi PKC zeta mRNA only in brain. PKC zeta transcripts were most abundant in lung and kidney (2.7 and 4.7 kb mRNAs), correlating with the tissue profile of PKC zeta immunoreactivity in Western blots. Probes complementary to the common V5 and C1 domains detected both PKC zeta and psi PKC zeta transcripts. Interestingly, the C1 probe also detected an abundant novel 1.75 kb mRNA in brain and heart, suggesting the existence of an additional PKC zeta-related species. This work, therefore, also emphasizes the importance of careful choice of oligonucleotide and cDNA probes to study PKC zeta mRNA.

Sign in / Sign up

Export Citation Format

Share Document