scholarly journals Elucidating the functional role of predicted miRNAs in post-transcriptional gene regulation along with symbiosis in Medicago truncatula

2018 ◽  
Author(s):  
Roy Chowdhury Moumita ◽  
Jolly Basak ◽  
Ranjit Prasad Bahadur

AbstractNon-coding RNAs (ncRNAs) are found to be important regulator of gene expression because of their ability to modulate post-transcriptional processes. microRNAs are small ncRNAs which inhibit translational and post-transcriptional processes whereas long ncRNAs are found to regulate both transcriptional and post-transcriptional gene expression. Medicago truncatula is a well-known model plant for studying legume biology and is also used as a forage crop. In spite of its importance in nitrogen fixation and soil fertility improvement, little information is available about Medicago ncRNAs that play important role in symbiosis. To understand the role of Medicago ncRNAs in symbiosis and regulation of transcription factors, we have identified novel miRNAs and tried to establish an interaction model with their targets. 149 novel miRNAs are predicted along with their 770 target proteins. We have shown that 51 of these novel miRNAs are targeting 282 lncRNAs. We have analyzed the interactions between miRNAs and their target mRNAs as well as their targets on lncRNAs. Role of Medicago miRNAs in the regulation of various transcription factors were also elucidated. Knowledge gained from this study will have a positive impact on the nitrogen fixing ability of this important model plant, which in turn will improve the soil fertility.

2020 ◽  
Vol 15 (2) ◽  
pp. 108-120 ◽  
Author(s):  
Moumita Roy Chowdhury ◽  
Jolly Basak ◽  
Ranjit Prasad Bahadur

Background: microRNAs are small non-coding RNAs which inhibit translational and post-transcriptional processes whereas long non-coding RNAs are found to regulate both transcriptional and post-transcriptional gene expression. Medicago truncatula is a well-known model plant for studying legume biology and is also used as a forage crop. In spite of its importance in nitrogen fixation and soil fertility improvement, little information is available about Medicago non-coding RNAs that play important role in symbiosis. Objective: In this study we have tried to understand the role of Medicago ncRNAs in symbiosis and regulation of transcription factors. Methods: We have identified novel miRNAs by computational methods considering various parameters like length, MFEI, AU content, SSR signatures and tried to establish an interaction model with their targets obtained through psRNATarget server. Results: 149 novel miRNAs are predicted along with their 770 target proteins. We have also shown that 51 of these novel miRNAs are targeting 282 lncRNAs. Conclusion: In this study role of Medicago miRNAs in the regulation of various transcription factors are elucidated. Knowledge gained from this study will have a positive impact on the nitrogen fixing ability of this important model plant, which in turn will improve the soil fertility.


2018 ◽  
Author(s):  
Adam J. Dobson ◽  
Richard Boulton-McDonald ◽  
Lara Houchou ◽  
Ziyu Ren ◽  
Mimoza Hoti ◽  
...  

ABSTRACTIncreasing average population age, and the accompanying burden of ill health, is one of the public health crises of our time. Understanding the basic biology of the ageing process may help ameliorate the pathologies that characterise old age. Ageing can be modulated, often through changes in gene expression where regulation of transcription plays a pivotal role. Activities of Forkhead transcription factors (TFs) are known to extend lifespan, but detailed knowledge of the broader transcriptional networks that promote longevity is lacking. This study focuses on the E twenty-six (ETS) family of TFs. This family of TFs is large, conserved across metazoa, and known to play roles in development and cancer, but the role of its members in ageing has not been studied extensively. InDrosophila, an ETS transcriptional repressor,Aop, and an ETS transcriptional activator,Pnt, are known to genetically interact withFoxoand activatingAopis sufficient to extend lifespan. Here, it is shown thatAopandFoxoeffect a related gene-expression programme. Additionally,Aopcan modulateFoxo’s transcriptional output to moderate or synergise withFoxoactivity depending on promoter context, bothin vitroandin vivo.In vivogenome-wide mRNA expression analysis in response toAop,PntorFoxoindicated, and further experiments confirmed, that combinatorial activities of the three TFs dictate metabolic status, and that direct reduction ofPntactivity is sufficient to promote longevity. The role of ETS factors in longevity was not limited toPntandAop. Knockdown ofEts21corEip74EFin distinct cell types also extended lifespan, revealing that lifespan is limited by transcription from the ETS binding site in multiple cellular contexts. Reducing the activity of theC. elegansETS TFLin-1also extended lifespan, a finding that corroborates established evidence of roles of this TF family in ageing. Altogether, these results reveal the ETS family of TFs as pervasive and evolutionarily conserved brokers of longevity.


2005 ◽  
pp. 168-191
Author(s):  
Fulvio Della Ragione ◽  
Valeria Cucciolla ◽  
Adriana Borriello ◽  
Vincenzo Zappia

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Heini M. Natri ◽  
Melissa A. Wilson ◽  
Kenneth H. Buetow

Abstract Background Sex-differences in cancer occurrence and mortality are evident across tumor types; men exhibit higher rates of incidence and often poorer responses to treatment. Targeted approaches to the treatment of tumors that account for these sex-differences require the characterization and understanding of the fundamental biological mechanisms that differentiate them. Hepatocellular Carcinoma (HCC) is the second leading cause of cancer death worldwide, with the incidence rapidly rising. HCC exhibits a male-bias in occurrence and mortality, but previous studies have failed to explore the sex-specific dysregulation of gene expression in HCC. Methods Here, we characterize the sex-shared and sex-specific regulatory changes in HCC tumors in the TCGA LIHC cohort using combined and sex-stratified differential expression and eQTL analyses. Results By using a sex-specific differential expression analysis of tumor and tumor-adjacent samples, we uncovered etiologically relevant genes and pathways differentiating male and female HCC. While both sexes exhibited activation of pathways related to apoptosis and cell cycle, males and females differed in the activation of several signaling pathways, with females showing PPAR pathway enrichment while males showed PI3K, PI3K/AKT, FGFR, EGFR, NGF, GF1R, Rap1, DAP12, and IL-2 signaling pathway enrichment. Using eQTL analyses, we discovered germline variants with differential effects on tumor gene expression between the sexes. 24.3% of the discovered eQTLs exhibit differential effects between the sexes, illustrating the substantial role of sex in modifying the effects of eQTLs in HCC. The genes that showed sex-specific dysregulation in tumors and those that harbored a sex-specific eQTL converge in clinically relevant pathways, suggesting that the molecular etiologies of male and female HCC are partially driven by differential genetic effects on gene expression. Conclusions Sex-stratified analyses detect sex-specific molecular etiologies of HCC. Overall, our results provide new insight into the role of inherited genetic regulation of transcription in modulating sex-differences in HCC etiology and provide a framework for future studies on sex-biased cancers.


2007 ◽  
Vol 293 (2) ◽  
pp. L480-L490 ◽  
Author(s):  
Jinming Zhao ◽  
Richart Harper ◽  
Aaron Barchowsky ◽  
Y. P. Peter Di

Activation and regulation of transcription factors (TFs) are the major mechanisms regulating changes in gene expression upon environmental exposure. Tobacco smoke (TS) is a complex mixture of chemicals, each of which could act through different signal cascades, leading to the regulation of distinct TFs and alterations in subsequent gene expression. We proposed that TS exposure affects inflammatory gene expression at the transcriptional level by modulating the DNA binding activities of TFs. To investigate transcriptional regulation upon TS exposure, a protein/DNA array was applied to screen TFs that are affected by TS exposure. This array-based screening allowed us to simultaneously detect 244 different TFs. Our results indicated that multiple TFs were rapidly activated upon TS exposure. DNA-binding activity of differentially expressed TFs was confirmed by EMSA. Our results showed that at least 20 TFs displayed more than twofold expressional changes after smoke treatment. Ten smoke-induced TFs, including NF-κB, VDR, ISRE, and RSRFC4, were involved in MAPK signaling pathways. The NF-κB family, which is involved in inflammation-induced gene activation, was selected for further study to characterize TS exposure-induced transcriptional activation. Western blot analysis and immunofluorescence microscopy indicated that TS exposure induced phosphorylation of IκB and translocation of NF-κB p65/p50 heterodimers into the nucleus. This activity was abrogated by the MAPK inhibitors PD98059 and U0126. Our results confirmed that activation of MAPK signaling pathways by TS exposure increased transcriptional activity of NF-κB. These data provide a potential mechanism for TS-induced inflammatory gene expression.


2019 ◽  
Author(s):  
Heini M Natri ◽  
Melissa A Wilson ◽  
Kenneth H Buetow

Abstract Background: Sex-differences in cancer occurrence and mortality are evident across tumor types; men exhibit higher rates of incidence and often poorer responses to treatment. Targeted approaches to the treatment of tumors that account for these sex-differences require the characterization and understanding of the fundamental biological mechanisms that differentiate them. Hepatocellular Carcinoma (HCC) is the second leading cause of cancer death worldwide, with the incidence rapidly rising. HCC exhibits a male-bias in occurrence and mortality, but previous studies have failed to explore the sex-specific dysregulation of gene expression in HCC. Methods: Here, we characterize the sex-shared and sex-specific regulatory changes in HCC tumors in the TCGA LIHC cohort using combined and sex-stratified differential expression and eQTL analyses. Results: By using a sex-specific differential expression analysis of tumor and tumor-adjacent samples, we uncovered etiologically relevant genes and pathways differentiating male and female HCC. While both sexes exhibited activation of pathways related to apoptosis and cell cycle, males and females differed in the activation of several signaling pathways, with females showing PPAR pathway enrichment while males showed PI3K, 305 PI3K/AKT, FGFR, EGFR, NGF, GF1R, Rap1, DAP12, and IL-2 signaling pathway enrichment. Using eQTL analyses, we discovered germline variants with differential effects on tumor gene expression between the sexes. 24.3% of the discovered eQTLs exhibit differential effects between the sexes, illustrating the substantial role of sex in modifying the effects of eQTLs in HCC. The genes that showed sex-specific dysregulation in tumors and those that harbored a sex-specific eQTL converge in clinically relevant pathways, suggesting that the molecular etiologies of male and female HCC are partially driven by differential genetic effects on gene expression. Conclusions: Sex-stratified analyses detect sex-specific molecular etiologies of HCC. Overall, our results provide new insight into the role of inherited genetic regulation of transcription in modulating sex-differences in HCC etiology and provide a framework for future studies on sex-biased cancers.


Sign in / Sign up

Export Citation Format

Share Document