scholarly journals Control of Cell Growth and Proliferation by the Tribbles Pseudokinase: Lessons from Drosophila

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 883
Author(s):  
Leonard L. Dobens ◽  
Christopher Nauman ◽  
Zachary Fischer ◽  
Xiaolan Yao
Keyword(s):  
Cell Growth ◽  
Tumor Formation ◽  
Hippo Signaling ◽  
Lung Cancers ◽  
Stem Cell Quiescence ◽  
Enhancer Binding Protein ◽  
Drosophila Model ◽  
Proliferation And Differentiation ◽  
Regulate Cell Growth ◽  
Cell Growth And Proliferation

The Tribbles (Trib) family of pseudokinase proteins regulate cell growth, proliferation, and differentiation during normal development and in response to environmental stress. Mutations in human Trib isoforms (Trib1, 2, and 3) have been associated with metabolic disease and linked to leukemia and the formation of solid tumors, including melanomas, hepatomas, and lung cancers. Drosophila Tribbles (Trbl) was the first identified member of this sub-family of pseudokinases and shares a conserved structure and similar functions to bind and direct the degradation of key mediators of cell growth and proliferation. Common Trib targets include Akt kinase (also known as protein kinase B), C/EBP (CAAT/enhancer binding protein) transcription factors, and Cdc25 phosphatases, leading to the notion that Trib family members stand athwart multiple pathways modulating their growth-promoting activities. Recent work using the Drosophila model has provided important insights into novel facets of conserved Tribbles functions in stem cell quiescence, tissue regeneration, metabolism connected to insulin signaling, and tumor formation linked to the Hippo signaling pathway. Here we highlight some of these recent studies and discuss their implications for understanding the complex roles Tribs play in cancers and disease pathologies.

scholarly journals An aminoacylation independent activity of PheRS/FARS promotes growth and proliferation

2020 ◽  
Author(s):  
Manh Tin Ho ◽  
Jiongming Lu ◽  
Beat Suter
Keyword(s):  
Cell Growth ◽  
Trna Synthetase ◽  
Tumor Formation ◽  
Follicle Cells ◽  
Strong Increase ◽  
Trna Synthetases ◽  
Elevated Expression ◽  
Wing Discs ◽  
Cell Growth And Proliferation ◽  
Normal Twin

Summary / AbstractAminoacyl-tRNA synthetases (aaRSs) not only load the appropriate amino acid onto their cognate tRNA, but many of them perform additional functions that are not necessarily related to their canonical activities. Phenylalanyl-tRNA synthetase (PheRS/FARS) levels are elevated in various cancer cells compared to their normal cell counterparts. However, whether and how these levels might contribute to tumor formation was not clear. Here, we show that PheRS is required for cell growth and proliferation. Interestingly, elevated expression of the α-PheRS subunit alone stimulates cell growth and proliferation. In the wing discs system, this leads to a strong increase of mitotic cells. Clonal analysis of twin spots in dividing follicle cells revealed that elevated expression of the α-PheRS subunit causes cells to grow and proliferate about 25% faster than their normal twin cells. Importantly, this stimulation of growth and proliferation neither required the β-PheRS subunit nor the aminoacylation activity, and it did not visibly stimulate translation. These results, therefore, revealed a non-canonical function of an ancient housekeeping enzyme, providing novel insight into its roles in health and diseases.

scholarly journals HOXB4 inhibits the proliferation and tumorigenesis of cervical cancer cells by downregulating the activity of Wnt/β-catenin signaling pathway

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Dan Lei ◽  
Wen-Ting Yang ◽  
Peng-Sheng Zheng
Keyword(s):  
Cervical Cancer ◽  
Cell Growth ◽  
Signaling Pathway ◽  
Cancer Cell ◽  
Tumor Formation ◽  
Cervical Cancer Cell ◽  
Cancer Cell Growth ◽  
Bioinformatics Analyses

AbstractHomeobox B4 (HOXB4), which belongs to the homeobox (HOX) family, possesses transcription factor activity and has a crucial role in stem cell self-renewal and tumorigenesis. However, its biological function and exact mechanism in cervical cancer remain unknown. Here, we found that HOXB4 was markedly downregulated in cervical cancer. We demonstrated that HOXB4 obviously suppressed cervical cancer cell proliferation and tumorigenic potential in nude mice. Additionally, HOXB4-induced cell cycle arrest at the transition from the G0/G1 phase to the S phase. Conversely, loss of HOXB4 promoted cervical cancer cell growth both in vitro and in vivo. Bioinformatics analyses and mechanistic studies revealed that HOXB4 inhibited the activity of the Wnt/β-catenin signaling pathway by direct transcriptional repression of β-catenin. Furthermore, β-catenin re-expression rescued HOXB4-induced cervical cancer cell defects. Taken together, these findings suggested that HOXB4 directly transcriptional repressed β-catenin and subsequently inactivated the Wnt/β-catenin signaling pathway, leading to significant inhibition of cervical cancer cell growth and tumor formation.

scholarly journals Enhanced Myc Expression in Silkworm Silk Gland Promotes DNA Replication and Silk Production

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 361
Author(s):  
Wenliang Qian ◽  
Yan Yang ◽  
Zheng Li ◽  
Yuting Wu ◽  
Xuechuan He ◽  
...  
Keyword(s):  
Dna Replication ◽  
Cell Growth ◽  
Silk Gland ◽  
Biological Functions ◽  
Gland Cells ◽  
Silk Production ◽  
Myc Gene ◽  
Cell Growth And Proliferation ◽  
Silkworm Silk ◽  
Posterior Silk Gland

Silkworm is an economically important insect that synthetizes silk proteins for silk production in silk gland, and silk gland cells undergo endoreplication during larval period. Transcription factor Myc is essential for cell growth and proliferation. Although silkworm Myc gene has been identified previously, its biological functions in silkworm silk gland are still largely unknown. In this study, we examined whether enhanced Myc expression in silk gland could facilitate cell growth and silk production. Based on a transgenic approach, Myc was driven by the promoter of the fibroin heavy chain (FibH) gene to be successfully overexpressed in posterior silk gland. Enhanced Myc expression in the PSG elevated FibH expression by about 20% compared to the control, and also increased the weight and shell rate of the cocoon shell. Further investigation confirmed that Myc overexpression increased nucleus size and DNA content of the PSG cells by promoting the transcription of the genes involved in DNA replication. Therefore, we conclude that enhanced Myc expression promotes DNA replication and silk protein expression in endoreplicating silk gland cells, which subsequently raises silk yield.

microRNA 21-mediated suppression of sprouty1 by Pokemon affects liver cancer cell growth and proliferation

2013 ◽  
Vol 114 (7) ◽  
pp. 1625-1633 ◽  
Author(s):  
Xiu-Li Jin ◽  
Qin-Sheng Sun ◽  
Feng Liu ◽  
Hong-Wei Yang ◽  
Min Liu ◽  
...  
Keyword(s):  
Cell Growth ◽  
Liver Cancer ◽  
Cancer Cell ◽  
Liver Cancer Cell ◽  
Cancer Cell Growth ◽  
Cell Growth And Proliferation

An oligomer complementary to c-myc mRNA inhibits proliferation of HL-60 promyelocytic cells and induces differentiation

1988 ◽  
Vol 8 (2) ◽  
pp. 963-973
Author(s):  
J T Holt ◽  
R L Redner ◽  
A W Nienhuis
Keyword(s):  
Cell Growth ◽  
Protein Concentration ◽  
Myeloid Differentiation ◽  
Sequence Specificity ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Steady State Levels ◽  
Cell Growth And Differentiation ◽  
Antisense Oligomer

To study the role of a nuclear proto-oncogene in the regulation of cell growth and differentiation, we inhibited HL-60 c-myc expression with a complementary antisense oligomer. This oligomer was stable in culture and entered cells, forming an intracellular duplex. Incubation of cells with the anti-myc oligomer decreased the steady-state levels of c-myc protein by 50 to 80%, whereas a control oligomer did not significantly affect the c-myc protein concentration. Direct inhibition of c-myc expression with the anti-myc oligomer was associated with a decreased cell growth rate and an induction of myeloid differentiation. Related antisense oligomers with 2- to 12-base-pair mismatches with c-myc mRNA did not influence HL-60 cells. Thus, the effects of the antisense oligomer exhibited sequence specificity, and furthermore, these effects could be reversed by hybridization competition with another complementary oligomer. Antisense inhibition of a nuclear proto-oncogene apparently bypasses cell surface events in affecting cell proliferation and differentiation.

Sign in / Sign up

Export Citation Format

Share Document