scholarly journals MiR-146a/b: a family with shared seeds and different roots

2017 ◽  
Vol 49 (4) ◽  
pp. 243-252 ◽  
Author(s):  
Mark R. Paterson ◽  
Alison J. Kriegel

MicroRNAs are small, noncoding, RNAs known for their powerful modulation of molecular processes, making them a major focus for studying pathological mechanisms. The human miR-146 family of microRNAs consists of two member genes, MIR146A and MIR146B. These two microRNAs are located on different chromosomes and exhibit differential regulation in many cases. However, they are nearly identical in sequence, sharing a seed region, and are thus predicted to target the same set of genes. A large proportion of the microRNA (miR)-146 literature focuses on its role in regulating the innate immune response in the context of various pathologies by modulating two widely studied target genes in the toll-like receptor signaling cascade. A growing subset of the literature reports a role of miR-146 in cardiovascular and renal disease, and data suggest there is exciting potential for miR-146 as a diagnostic and therapeutic target. Nevertheless, the published literature is confounded by unclear and imprecise language concerning the specific effects of the two miR-146 family members. The present review will compare the genomic origin and regulation of miR-146a and miR-146b, discuss some approaches to overcome analytical and experimental challenges, and summarize findings in major areas of miR-146 research. Moving forward, careful evaluation of miR-146a/b specificity in analytical and experimental approaches will aid researchers in elucidating the functional relevance of differential regulation of the miR-146 family members in health and disease.

2012 ◽  
Vol 44 (4) ◽  
pp. 237-244 ◽  
Author(s):  
Alison J. Kriegel ◽  
Yong Liu ◽  
Yi Fang ◽  
Xiaoqiang Ding ◽  
Mingyu Liang

The human miR-29 family of microRNAs has three mature members, miR-29a, miR-29b, and miR-29c. miR-29s are encoded by two gene clusters. Binding sites for several transcriptional factors have been identified in the promoter regions of miR-29 genes. The miR-29 family members share a common seed region sequence and are predicted to target largely overlapping sets of genes. However, the miR-29 family members exhibit differential regulation in several cases and different subcellular distribution, suggesting their functional relevance may not be identical. miR-29s directly target at least 16 extracellular matrix genes, providing a dramatic example of a single microRNA targeting a large group of functionally related genes. Strong antifibrotic effects of miR-29s have been demonstrated in heart, kidney, and other organs. miR-29s have also been shown to be proapoptotic and involved in the regulation of cell differentiation. It remains to be explored how various cellular effects of miR-29s determine functional relevance of miR-29s to specific diseases and how the miR-29 family members may function cooperatively or separately.


2013 ◽  
Vol 4 ◽  
Author(s):  
Loris R. Lopetuso ◽  
Saleem Chowdhry ◽  
Theresa T. Pizarro

Cells ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 75 ◽  
Author(s):  
Nicoletta Nuzziello ◽  
Loredana Ciaccia ◽  
Maria Liguori

Novel insights in the development of a precision medicine approach for treating the neurodegenerative diseases (NDDs) are provided by emerging advances in the field of pharmacoepigenomics. In this context, microRNAs (miRNAs) have been extensively studied because of their implication in several disorders related to the central nervous system, as well as for their potential role as biomarkers of diagnosis, prognosis, and response to treatment. Recent studies in the field of neurodegeneration reported evidence that drug response and efficacy can be modulated by miRNA-mediated mechanisms. In fact, miRNAs seem to regulate the expression of pharmacology target genes, while approved (conventional and non-conventional) therapies can restore altered miRNAs observed in NDDs. The knowledge of miRNA pharmacoepigenomics may offers new clues to develop more effective treatments by providing novel insights into interindividual variability in drug disposition and response. Recently, the therapeutic potential of miRNAs is gaining increasing attention, and miRNA-based drugs (for cancer) have been under observation in clinical trials. However, the effective use of miRNAs as therapeutic target still needs to be investigated. Here, we report a brief review of representative studies in which miRNAs related to therapeutic effects have been investigated in NDDs, providing exciting potential prospects of miRNAs in pharmacoepigenomics and translational medicine.


2000 ◽  
Vol 20 (16) ◽  
pp. 5797-5807 ◽  
Author(s):  
Julie Wells ◽  
Kathryn E. Boyd ◽  
Christopher J. Fry ◽  
Stephanie M. Bartley ◽  
Peggy J. Farnham

ABSTRACT E2F-mediated transcription is thought to involve binding of an E2F-pocket protein complex to promoters in the G0 phase of the cell cycle and release of the pocket protein in late G1, followed by release of E2F in S phase. We have tested this model by monitoring protein-DNA interactions in living cells using a formaldehyde cross-linking and immunoprecipitation assay. We find that E2F target genes are bound by distinct E2F-pocket protein complexes which change as cells progress through the cell cycle. We also find that certain E2F target gene promoters are bound by pocket proteins when such promoters are transcriptionally active. Our data indicate that the current model applies only to certain E2F target genes and suggest that Rb family members may regulate transcription in both G0 and S phases. Finally, we find that a given promoter can be bound by one of several different E2F-pocket protein complexes at a given time in the cell cycle, suggesting that cell cycle-regulated transcription is a stochastic, not a predetermined, process.


Author(s):  
Tibor Hortobágyi ◽  
Urs Granacher ◽  
Miguel Fernandez-del-Olmo ◽  
Glyn Howatson ◽  
Andrea Manca ◽  
...  

2021 ◽  
pp. 1-18
Author(s):  
Vignesh Muralidharan ◽  
Adam R. Aron

Abstract The sensorimotor beta rhythm (∼13–30 Hz) is commonly seen in relation to movement. It is important to understand its functional/behavioral significance in both health and disease. Sorting out competing theories of sensorimotor beta is hampered by a paucity of experimental protocols in humans that manipulate/induce beta oscillations and test their putative effects on concurrent behavior. Here, we developed a novel behavioral paradigm to generate beta and then test its functional relevance. In two human experiments with scalp EEG (n = 11 and 15), we show that a movement instruction generates a high beta state (postmovement beta rebound), which then slows down subsequent movements required during that state. We also show that this high initial beta rebound related to reduced mu–beta desynchronization for the subsequent movement and further that the temporal features of the beta state, that is, the beta bursts related to the degree of slowing. These results suggest that increased sensorimotor beta in the postmovement period corresponds to an inhibitory state—insofar as it retards subsequent movement. By demonstrating a behavioral method by which people can proactively create a high beta state, our paradigm provides opportunities to test the effect of this state on sensations and affordances. It also suggests related experiments using motor imagery rather than actual movement, and this could later be clinically relevant, for example, in tic disorder.


2020 ◽  
Author(s):  
Jacob J. Crow ◽  
Allan R. Albig

ABSTRACTNotch signaling is essential for multicellular life, regulating core functions such as cellular identity, differentiation, and fate. These processes require highly sensitive systems to avoid going awry, and one such regulatory mechanism is through Notch intracellular domain dimerization. Select Notch target genes contain sequence-paired sites (SPS); motifs in which two Notch transcriptional activation complexes can bind and interact through Notch’s ankyrin domain, resulting in enhanced transcriptional activation. This mechanism has been mostly studied through Notch1, and to date, the abilities of the other Notch family members have been left unexplored. Through the utilization of minimalized, SPS-driven luciferase assays, we were able to test the functional capacity of Notch dimers. Here we show that each family member is capable of dimerization-induced signaling, following the same stringent requirements as seen with Notch1. Interestingly, we identified a mechanical difference between canonical and cryptic SPSs, leading to differences in their dimerization-induced regulation. Finally, we profiled the Notch family members’ SPS gap distance preferences and found that they all prefer a 16-nucleotide gap, with little room for variation. In summary, this work highlights the potent and highly specific nature of Notch dimerization and refines the scope of this regulatory function.


2005 ◽  
Vol 393 (1) ◽  
pp. 397-409 ◽  
Author(s):  
Steven O. Simmons ◽  
Jonathan M. Horowitz

Nkx3.1 is a homeodomain-containing transcription factor that is expressed early in the development of the prostate gland and is believed to play an important role in the differentiation of prostatic epithelia. Loss of Nkx3.1 protein expression is often an early event in prostate tumorigenesis, and the abundance of Nkx3.1-negative epithelial cells increases with disease progression. In a number of systems, homeodomain proteins collaborate with zinc-finger-containing transcription factors to bind and regulate target genes. In the present paper, we report that Nkx3.1 collaborates with Sp-family members in the regulation of PSA (prostate-specific antigen) in prostate-derived cells. Nkx3.1 forms protein complexes with Sp proteins that are dependent on their respective DNA-binding domains and an N-terminal segment of Nkx3.1, and Nkx3.1 negatively regulates Sp-mediated transcription via Trichostatin A-sensitive and -insensitive mechanisms. A distal 1000 bp portion of the PSA promoter is required for transrepression by Nkx3.1, although Nkx3.1 DNA-binding activity is itself not required. We conclude that Nkx3.1 negatively regulates Sp-mediated transcription via the tethering of histone deacetylases and/or by inhibiting the association of Sp proteins with co-activators.


2010 ◽  
Vol 191 (4) ◽  
pp. 809-825 ◽  
Author(s):  
Stacey E. Wirt ◽  
Adam S. Adler ◽  
Véronique Gebala ◽  
James M. Weimann ◽  
Bethany E. Schaffer ◽  
...  

The ability of progenitor cells to exit the cell cycle is essential for proper embryonic development and homeostasis, but the mechanisms governing cell cycle exit are still not fully understood. Here, we tested the requirement for the retinoblastoma (Rb) protein and its family members p107 and p130 in G0/G1 arrest and differentiation in mammalian cells. We found that Rb family triple knockout (TKO) mouse embryos survive until days 9–11 of gestation. Strikingly, some TKO cells, including in epithelial and neural lineages, are able to exit the cell cycle in G0/G1 and differentiate in teratomas and in culture. This ability of TKO cells to arrest in G0/G1 is associated with the repression of key E2F target genes. Thus, G1 arrest is not always dependent on Rb family members, which illustrates the robustness of cell cycle regulatory networks during differentiation and allows for the identification of candidate pathways to inhibit the expansion of cancer cells with mutations in the Rb pathway.


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