Changes associated with aging and replicative senescence in the regulation of transcription factor nuclear factor-κB

Both the aging of animals and the senescence of cultured cells involve an altered pattern of gene expression, suggesting changes in transcription factor regulation. We studied age-related changes in transcription factors nuclear factor (NF)-κB, activator protein factor-1 (AP-1) and Sp-1 by using electrophoretic mobility shift binding assays; we also analysed changes in the protein components of NF-κB complex with Western blot assays. Nuclear and cytoplasmic extracts were prepared from heart, liver, kidney and brain of young adult and old NMRI mice and Wistar rats as well as from presenescent, senescent and simian virus 40-immortalized human WI-38 fibroblasts. Aging of both mice and rats induced a strong and consistent increase in the nuclear binding activity of NF-κB factor in all tissues studied, whereas those of AP-1 and Sp-1 decreased, e.g. in liver. Protein levels of p50, p52 and p65 components of the NF-κB complex did not show any age-associated changes in the cytoplasmic fraction but in the nuclear fraction the level of p52 strongly increased in heart and liver during aging. The protein levels of inhibitory IκB-α and Bcl-3 components were not affected by aging in any of the tissues studied. Replicative cellular senescence of human WI-38 fibroblasts induced a strong decrease in nuclear NF-κB, AP-1 and Sp-1 binding activities. Protein levels of p50 and p52 components of NF-κB complex were decreased in the nuclear fraction of senescent WI-38 fibroblasts but in the cytoplasm of senescent fibroblasts the level of p65 protein was increased. Cellular senescence also slightly decreased the protein levels of IκB-α and Bcl-3. Transfection assays with NF-κB-enhancer-driven chloramphenicol acetyltransferase reporter gene showed a significant down-regulation of NF-κB promoter activity in senescent WI-38 fibroblasts. Results suggest that the aging process might be regulated differently in tissues and cultured fibroblasts, perhaps reflecting differences between mitotic and post-mitotic cells. In tissues, aging seems to involve specific changes in the regulation of NF-κB components and perhaps also changes in the DNA-binding affinities of the NF-κB complex.

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Recent Discoveries on the Involvement of Krüppel-Like Factor 4 in the Most Common Cancer Types

International Journal of Molecular Sciences ◽

10.3390/ijms21228843 ◽

2020 ◽

Vol 21 (22) ◽

pp. 8843

Author(s):

Agnieszka Taracha-Wisniewska ◽

Grzegorz Kotarba ◽

Sebastian Dworkin ◽

Tomasz Wilanowski

Keyword(s):

Transcription Factor ◽

Regulation Of Transcription ◽

Critical Function ◽

Post Translational Modifications ◽

Tumor Subtypes ◽

Protein Levels ◽

Common Cancer ◽

Cancer Types ◽

Cellular Integrity ◽

Upstream Regulators

Krüppel-like factor 4 (KLF4) is a transcription factor highly conserved in evolution. It is particularly well known for its role in inducing pluripotent stem cells. In addition, KLF4 plays many roles in cancer. The results of most studies suggest that KLF4 is a tumor suppressor. However, the functioning of KLF4 is regulated at many levels. These include regulation of transcription, alternative splicing, miRNA, post-translational modifications, subcellular localization, protein stability and interactions with other molecules. Simple experiments aimed at assaying transcript levels or protein levels fail to address this complexity and thus may deliver misleading results. Tumor subtypes are also important; for example, in prostate cancer KLF4 is highly expressed in indolent tumors where it impedes tumor progression, while it is absent from aggressive prostate tumors. KLF4 is important in regulating response to many known drugs, and it also plays a role in tumor microenvironment. More and more information is available about upstream regulators, downstream targets and signaling pathways associated with the involvement of KLF4 in cancer. Furthermore, KLF4 performs critical function in the overall regulation of tissue homeostasis, cellular integrity, and progression towards malignancy. Here we summarize and analyze the latest findings concerning this fascinating transcription factor.

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Ultraviolet B Regulation of Transcription Factor Families: Roles of Nuclear Factor-kappa B (NF-κB) and Activator Protein-1 (AP-1) in UVB-Induced Skin Carcinogenesis

Current Cancer Drug Targets ◽

10.2174/156800907780809714 ◽

2007 ◽

Vol 7 (4) ◽

pp. 325-334 ◽

Cited By ~ 107

Author(s):

S. Cooper ◽

G. Bowden

Keyword(s):

Transcription Factor ◽

Nuclear Factor Kappa B ◽

Skin Carcinogenesis ◽

Ultraviolet B ◽

Regulation Of Transcription ◽

Nuclear Factor ◽

Activator Protein 1 ◽

Activator Protein ◽

Nuclear Factor Kappa

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Kid-1, a putative renal transcription factor: regulation during ontogeny and in response to ischemia and toxic injury

Molecular and Cellular Biology ◽

10.1128/mcb.13.3.1933-1942.1993 ◽

1993 ◽

Vol 13 (3) ◽

pp. 1933-1942

Author(s):

R Witzgall ◽

E O'Leary ◽

R Gessner ◽

A J Ouellette ◽

J V Bonventre

Keyword(s):

Transcription Factor ◽

Dna Binding ◽

Zinc Finger ◽

Rat Kidney ◽

Zinc Fingers ◽

Simian Virus 40 ◽

Regulation Of Transcription ◽

Mrna Levels ◽

Zinc Finger Region ◽

In Cells

We have identified a new putative transcription factor from the rat kidney, termed Kid-1 (for kidney, ischemia and developmentally regulated gene 1). Kid-1 belongs to the C2H2 class of zinc finger genes. Its mRNA accumulates with age in postnatal renal development and is detected predominantly in the kidney. Kid-1 mRNA levels decline after renal injury secondary to ischemia or folic acid administration, two insults which result in epithelial cell dedifferentiation, followed by regenerative hyperplasia and differentiation. The low expression of Kid-1 early in postnatal development, and when renal tissue is recovering after injury, suggests that the gene product is involved in establishment of a differentiated phenotype and/or regulation of the proliferative response. The deduced protein contains 13 C2H2 zinc fingers at the COOH end in groups of 4 and 9 separated by a 32-amino-acid spacer. There are consensus sites for phosphorylation in the NH2 terminus non-zinc finger region as well as in the spacer region between zinc fingers 4 and 5. A region of the deduced protein shares extensive homology with a catalytic region of Raf kinases, a feature shared only with TFIIE among transcription factors. To determine whether Kid-1 can modulate transcription, a chimeric construct encoding the Kid-1 non-zinc finger region (sense or antisense) and the DNA-binding region of GAL4 was transfected into COS and LLC-PK1 cells together with a chloramphenicol acetyltransferase (CAT) reporter plasmid containing GAL4 binding sites, driven by either a minimal promoter or a simian virus 40 enhancer. CAT activity was markedly inhibited in cells transfected with the sense construct compared with the activity in cells transfected with the antisense construct. To our knowledge, this pattern of developmental regulation, kidney expression, and regulation of transcription is unique among the C2H2 class of zinc finger-containing DNA-binding proteins.

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HSP90 inhibitors enhance differentiation and MITF (microphthalmia transcription factor) activity in osteoclast progenitors

Biochemical Journal ◽

10.1042/bj20121626 ◽

2013 ◽

Vol 451 (2) ◽

pp. 235-244 ◽

Cited By ~ 42

Author(s):

A. Gabrielle J. van der Kraan ◽

Ryan C. C. Chai ◽

Preetinder P. Singh ◽

Benjamin J. Lang ◽

Jiake Xu ◽

...

Keyword(s):

Transcription Factor ◽

Transforming Growth Factor ◽

Osteoclast Differentiation ◽

Osteoclast Formation ◽

Mouse Bone Marrow ◽

Nuclear Factor ◽

Hsp90 Inhibitors ◽

Activated T Cells ◽

Atpase Subunit ◽

Protein Levels

The HSP90 (heat-shock protein 90) inhibitor 17-AAG (17-allylamino-demethoxygeldanamycin) increases osteoclast formation both in vitro and in vivo, an action that can enhance cancer invasion and growth in the bone microenvironment. The cellular mechanisms through which 17-AAG exerts this action are not understood. Thus we sought to clarify the actions of 17-AAG on osteoclasts and determine whether other HSP90 inhibitors had similar properties. We determined that 17-AAG and the structurally unrelated HSP90 inhibitors CCT018159 and NVP-AUY922 dose-dependently increased RANKL [receptor activator of NF-κB (nuclear factor κB) ligand]-stimulated osteoclastogenesis in mouse bone marrow and pre-osteoclastic RAW264.7 cell cultures. Moreover, 17-AAG also enhanced RANKL- and TNF (tumour necrosis factor)-elicited osteoclastogenesis, but did not affect RANKL-induced osteoclast survival, suggesting that only differentiation mechanisms are targeted. 17-AAG affected the later stages of progenitor maturation (after 3 days of incubation), whereas the osteoclast formation enhancer TGFβ (transforming growth factor β) acted prior to this, suggesting different mechanisms of action. In studies of RANKL-elicited intracellular signalling, 17-AAG treatment did not increase c-Fos or NFAT (nuclear factor of activated T-cells) c1 protein levels nor did 17-AAG increase activity in luciferase-based NF-κB- and NFAT-response assays. In contrast, 17-AAG treatment (and RANKL treatment) increased both MITF (microphthalmia-associated transcription factor) protein levels and MITF-dependent vATPase-d2 (V-type proton ATPase subunit d2) gene promoter activity. These results indicate that HSP90 inhibitors enhance osteoclast differentiation in an NFATc1-independent manner that involves elevated MITF levels and activity.

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Biphasic Regulation of Transcription Factor Nuclear Factor-κB Activity in Human Endothelial Cells by Lysophosphatidylcholine Through Protein Kinase C–Mediated Pathway

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/01.atv.18.4.568 ◽

1998 ◽

Vol 18 (4) ◽

pp. 568-576 ◽

Cited By ~ 52

Author(s):

Seigo Sugiyama ◽

Kiyotaka Kugiyama ◽

Nobuhiko Ogata ◽

Hideki Doi ◽

Yasutaka Ota ◽

...

Keyword(s):

Endothelial Cells ◽

Transcription Factor ◽

Protein Kinase C ◽

Protein Kinase ◽

Nuclear Factor Κb ◽

Regulation Of Transcription ◽

Nuclear Factor ◽

Human Endothelial Cells ◽

Kinase C ◽

Transcription Factor Nuclear Factor

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Kid-1, a putative renal transcription factor: regulation during ontogeny and in response to ischemia and toxic injury.

Molecular and Cellular Biology ◽

10.1128/mcb.13.3.1933 ◽

1993 ◽

Vol 13 (3) ◽

pp. 1933-1942 ◽

Cited By ~ 57

Author(s):

R Witzgall ◽

E O'Leary ◽

R Gessner ◽

A J Ouellette ◽

J V Bonventre

Keyword(s):

Transcription Factor ◽

Dna Binding ◽

Zinc Finger ◽

Rat Kidney ◽

Zinc Fingers ◽

Simian Virus 40 ◽

Regulation Of Transcription ◽

Mrna Levels ◽

Zinc Finger Region ◽

In Cells

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Transcriptional regulation of rat liver protein disulphide-isomerase gene by insulin and in diabetes

Biochemical Journal ◽

10.1042/bj2670317 ◽

1990 ◽

Vol 267 (2) ◽

pp. 317-323 ◽

Cited By ~ 26

Author(s):

A Nieto ◽

E Mira ◽

J G Castaño

Keyword(s):

Rat Liver ◽

Insulin Treatment ◽

Diabetic Rats ◽

Regulation Of Transcription ◽

Liver Protein ◽

Gene Encoding ◽

Protein Disulphide Isomerase ◽

Multifunctional Protein ◽

Protein Levels

The mRNA encoding for rat protein disulphide-isomerase (PDI) increases 3-fold in the liver of diabetic rats and is accompanied by similar changes at the protein level. Long treatment (for 3 days) of diabetic rats with insulin reverses this effect of diabetes both at the mRNA and protein levels. The higher expression of rat PDI mRNA in diabetes is due to an increase in the transcriptional rate of the gene, and insulin treatment of diabetic animals produces within 30 min a decrease in the level of transcription of PDI gene, as judged by nuclear run-on transcription experiments performed in vivo. These results clearly show a role for insulin in the regulation of transcription of the gene encoding this multifunctional protein in rat liver.

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Vitamin B6 Deficiency can Reduce Fuel Storage and Utilization in Physically Trained Rats

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.78.2.64 ◽

2008 ◽

Vol 78 (2) ◽

pp. 64-69 ◽

Cited By ~ 1

Author(s):

Choi ◽

Cho

Keyword(s):

Skeletal Muscle ◽

Fatty Acid ◽

Muscle Protein ◽

Plasma Free Fatty Acid ◽

Vitamin B ◽

Liver Protein ◽

Protein Levels ◽

Before And After ◽

Fuel Storage ◽

Exercise Muscle

This study investigated the effect of vitamin B6 deficiency on the utilization and recuperation of stored fuel in physically trained rats. 48 rats were given either vitamin B6-deficient (B6–) diet or control (B6+) diet for 4 weeks and were trained on treadmill for 30 minutes daily. All animals were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed. Animals in the AE group were allowed to take a rest for 2 hours after being exercised like the DE group. Glucose and free fatty acids were compared in plasma. Glycogen and triglyceride were compared in liver and skeletal muscle. Protein levels were compared in plasma, liver, and skeletal muscle. Compared with the B6+ group, plasma glucose levels of the B6– group were significantly lower before and after exercise. Muscle glycogen levels of the B6– group were significantly lower than those of the B6+ group regardless of exercise. The liver glycogen level of the B6– group was also significantly lower than that of B6+ group during and after exercise. Before exercise, plasma free fatty acid levels were not significantly different between the B6+ and B6– groups, and plasma free fatty acid levels of the B6– group were significantly lower during and after exercise. The muscle triglyceride level of the B6– group was significantly lower than that of the B6+ group before exercise, and there were no differences between B6+ and B6– groups during and after exercise. Liver triglyceride levels were not significantly different between B6+ and B6– groups. Plasma protein levels of the B6– group were lower than those of B6+ before and after exercise. Muscle protein levels of the B6– group were not significantly different from those of the B6+ group. Liver protein levels of the B6– group were significantly lower than that of the B6+ group after exercise. Liver protein levels of both B6+ and B6– groups were not significantly changed, regardless of exercise. Thus, it is suggested that vitamin B6 deficiency may reduce fuel storage and utilization with exercise in physically trained rats.

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