Identification of MdGRF genes and the necessary role of MdGRF02 in apple root growth regulation

Sirtuins (SIRTs) are NAD+-dependent deacetylases that regulate proliferation and cell death. In the human ovary, granulosa cells express sirtuin 1 (SIRT1), which has also been detected in human tumors derived from granulosa cells, i.e., granulosa cell tumors (GCTs), and in KGN cells. KGN cells are an established cellular model for the majority of GCTs and were used to explore the role of SIRT1. The SIRT1 activator SRT2104 increased cell proliferation. By contrast, the inhibitor EX527 reduced cell numbers, without inducing apoptosis. These results were supported by the outcome of siRNA-mediated silencing studies. A tissue microarray containing 92 GCTs revealed nuclear and/or cytoplasmic SIRT1 staining in the majority of the samples, and also, SIRT2-7 were detected in most samples. The expression of SIRT1–7 was not correlated with the survival of the patients; however, SIRT3 and SIRT7 expression was significantly correlated with the proliferation marker Ki-67, implying roles in tumor cell proliferation. SIRT3 was identified by a proteomic analysis as the most abundant SIRT in KGN. The results of the siRNA-silencing experiments indicate involvement of SIRT3 in proliferation. Thus, several SIRTs are expressed by GCTs, and SIRT1 and SIRT3 are involved in the growth regulation of KGN. If transferable to GCTs, these SIRTs may represent novel drug targets.

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The Arabidopsis Root Tip (Phospho)Proteomes at Growth-Promoting versus Growth-Repressing Conditions Reveal Novel Root Growth Regulators

Cells ◽

10.3390/cells10071665 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1665

Author(s):

Natalia Nikonorova ◽

Evan Murphy ◽

Cassio Flavio Fonseca de Lima ◽

Shanshuo Zhu ◽

Brigitte van de Cotte ◽

...

Keyword(s):

Cell Wall ◽

Root Growth ◽

Growth Regulators ◽

Growth Regulation ◽

Phosphorylation Site ◽

Primary Root ◽

Root Tip ◽

Arabidopsis Root ◽

Growth Promoting ◽

The Impact

Auxin plays a dual role in growth regulation and, depending on the tissue and concentration of the hormone, it can either promote or inhibit division and expansion processes in plants. Recent studies have revealed that, beyond transcriptional reprogramming, alternative auxin-controlled mechanisms regulate root growth. Here, we explored the impact of different concentrations of the synthetic auxin NAA that establish growth-promoting and -repressing conditions on the root tip proteome and phosphoproteome, generating a unique resource. From the phosphoproteome data, we pinpointed (novel) growth regulators, such as the RALF34-THE1 module. Our results, together with previously published studies, suggest that auxin, H+-ATPases, cell wall modifications and cell wall sensing receptor-like kinases are tightly embedded in a pathway regulating cell elongation. Furthermore, our study assigned a novel role to MKK2 as a regulator of primary root growth and a (potential) regulator of auxin biosynthesis and signalling, and suggests the importance of the MKK2 Thr31 phosphorylation site for growth regulation in the Arabidopsis root tip.

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Lymphoma models for B cell activation and tolerance. X. Anti-mu-mediated growth arrest and apoptosis of murine B cell lymphomas is prevented by the stabilization of myc.

Journal of Experimental Medicine ◽

10.1084/jem.179.1.221 ◽

1994 ◽

Vol 179 (1) ◽

pp. 221-228 ◽

Cited By ~ 68

Author(s):

G Fischer ◽

S C Kent ◽

L Joseph ◽

D R Green ◽

D W Scott

Keyword(s):

Growth Inhibition ◽

B Cell ◽

Antisense Oligonucleotides ◽

Growth Regulation ◽

Cell Activation ◽

Transforming Growth Factor ◽

B Cell Activation ◽

Tgf Beta ◽

B Cell Lymphomas

Treatment of the WEHI-2131 or CH31 B cell lymphomas with anti-mu or transforming growth factor (TGF)-beta leads to growth inhibition and subsequent cell death via apoptosis. Since anti-mu stimulates a transient increase in c-myc and c-fos transcription in these lymphomas, we examined the role of these proteins in growth regulation using antisense oligonucleotides. Herein, we demonstrate that antisense oligonucleotides for c-myc prevent both anti-mu- and TGF-beta-mediated growth inhibition in the CH31 and WEHI-231 B cell lymphomas, whereas antisense c-fos has no effect. Furthermore, antisense c-myc promotes the appearance of phosphorylated retinoblastoma protein in the presence of anti-mu and prevents the progression to apoptosis as measured by propidium iodide staining. Northern and Western analyses show that c-myc message and the levels of multiple myc proteins were maintained in the presence of antisense c-myc, results indicating that myc species are critical for the continuation of proliferation and the prevention of apoptosis. These data implicate c-myc in the negative signaling pathway of both TGF-beta and anti-mu.

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Role of Psoralen Receptors in Cell Growth Regulation

Psoralen DNA Photobiology ◽

10.1201/9781351076128-6 ◽

2018 ◽

pp. 135-148 ◽

Cited By ~ 1

Author(s):

Jeffrey D. Laskin ◽

Debra L. Laskin

Keyword(s):

Cell Growth ◽

Growth Regulation ◽

Cell Growth Regulation

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Effects of mixed saline and alkaline stress on the morphology and anatomy of Pisum sativum L.: The role of peroxidase and ascorbate oxidase in growth regulation

Archives of Biological Sciences ◽

10.2298/abs1301265k ◽

2013 ◽

Vol 65 (1) ◽

pp. 265-278 ◽

Cited By ~ 8

Author(s):

Kukavica Biljana ◽

Morina Filis ◽

Janjic Nina ◽

Boroja Mirela ◽

Jovanovic Lj. ◽

...

Keyword(s):

Pisum Sativum ◽

Growth Regulation ◽

Ascorbate Oxidase ◽

Alkaline Stress ◽

Pisum Sativum L

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Correlation of serum adiponectin and leptin concentrations with anthropometric parameters in newborns

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh1210595p ◽

2012 ◽

Vol 140 (9-10) ◽

pp. 595-599 ◽

Cited By ~ 13

Author(s):

Snezana Palcevska-Kocevska ◽

Natasa Aluloska ◽

Marija Krstevska ◽

Elena Shukarova-Angelovska ◽

Ljiljana Kojik ◽

...

Keyword(s):

Birth Weight ◽

Growth Regulation ◽

Physiological Role ◽

Mutual Relationship ◽

Anthropometric Parameters ◽

Serum Leptin ◽

Significant Difference ◽

Neonatal Growth ◽

Singleton Pregnancies

Introduction. It has been shown that some adipocytokines and their mutual relationship can be indicators of fetal and neonatal growth. Physiological role of leptin and adiponectin in fetal and neonatal growth is not well established. Objectives. The aim of this study was to assess the correlation of the anthropometrics parameters and serum concentration of leptin and adiponectin levels in healthy newborns. Methods. A cohort of 110 neonates, born after uncomplicated singleton pregnancies at term, were classified as AGA (n=60), SGA (n=30) and LGA (n=20) according to the Lubchenco curves. Anthropometric parameters of the neonates: birth weight (BW), birth length (BL), body weight/body length ratio (BW/ BL), Body Mass Index (BMI) and Ponderal Index (PI) were recorded after birth. Results. Mean serum leptin and adiponectin levels in both sexes were not significantly different (male: 1.85?0.75; 29.51?22.89 and female: 2.06?0.99; 31.60?23.51 ng/mL). There was a significant difference between leptin levels in AGA and LGA newborns (1.93?0.84 vs. 3.12?1.50 ng/mL) (p<0.05), and in adiponectin levels between AGA and LGA compared to SGA newborns (32.8?23.29 and 43.40?31.24 vs. 12.67?2.43 ng/mL, respectivel; p<0.05; p<0.05). Leptin and adiponectin levels were positively correlated with BW (r=0.63 and r=0.41), BL (r=0.63, r=0.42), BW/BL (r=0.61, r=0.41), BMI (r=0.54, r=0.35), and PI (r=0.47, r=0.29, (p<0.01). Conclusion. Significantly higher adiponectin levels were found in AGA neonates compared to SGA neonates. Leptin and adiponectine levels were positively correlated with birth weight. These findings suggest that these adipocytokines may be involved in fetal growth regulation.

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Functional Domains of c-myc Promoter Binding Protein 1 Involved in Transcriptional Repression and Cell Growth Regulation

Molecular and Cellular Biology ◽

10.1128/mcb.19.4.2880 ◽

1999 ◽

Vol 19 (4) ◽

pp. 2880-2886 ◽

Cited By ~ 31

Author(s):

Asish K. Ghosh ◽

Robert Steele ◽

Ratna B. Ray

Keyword(s):

Amino Acids ◽

Cell Growth ◽

Dna Binding ◽

Transcriptional Repression ◽

Growth Regulation ◽

Transcriptional Repressor ◽

Binding Domain ◽

Dna Binding Domain ◽

Repressor Activity

ABSTRACT We initially identified c-myc promoter binding protein 1 (MBP-1), which negatively regulates c-myc promoter activity, from a human cervical carcinoma cell expression library. Subsequent studies on the biological role of MBP-1 demonstrated induction of cell death in fibroblasts and loss of anchorage-independent growth, reduced invasive ability, and tumorigenicity of human breast carcinoma cells. To investigate the potential role of MBP-1 as a transcriptional regulator, a chimeric protein containing MBP-1 fused to the DNA binding domain of the yeast transactivator factor GAL4 was constructed. This fusion protein exhibited repressor activity on the herpes simplex virus thymidine kinase promoter via upstream GAL4 DNA binding sites. Structure-function analysis of mutant MBP-1 in the context of the GAL4 DNA binding domain revealed that MBP-1 transcriptional repressor domains are located in the N terminus (amino acids 1 to 47) and C terminus (amino acids 232 to 338), whereas the activation domain lies in the middle (amino acids 140 to 244). The N-terminal domain exhibited stronger transcriptional repressor activity than the C-terminal region. When the N-terminal repressor domain was transferred to a potent activator, transcription was strongly inhibited. Both of the repressor domains contained hydrophobic regions and had an LXVXL motif in common. Site-directed mutagenesis in the repressor domains indicated that the leucine residues in the LXVXL motif are required for transcriptional repression. Mutation of the leucine residues in the common motif of MBP-1 also abrogated the repressor activity on the c-mycpromoter. In addition, the leucine mutant forms of MBP-1 failed to suppress cell growth in fibroblasts like wild-type MBP-1. Taken together, our results indicate that MBP-1 is a complex cellular factor containing multiple transcriptional regulatory domains that play an important role in cell growth regulation.

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