Differential expression, distribution, and function of PPAR-γ in the proximal and distal colon

2007 ◽  
Vol 30 (3) ◽  
pp. 342-353 ◽  
Author(s):  
Weidong Su ◽  
Craig R. Bush ◽  
Brian M. Necela ◽  
Shelly R. Calcagno ◽  
Nicole R. Murray ◽  
...  

Suppression of colon carcinogenesis by peroxisome proliferator-activated receptor (PPAR)-γ is likely due to some effect of PPAR-γ on normal colonic epithelial cells. However, our understanding of the effects of PPAR-γ in such cells is limited. We analyzed the abundance, distribution, and function of PPAR-γ in epithelial cells isolated from the murine proximal and distal colon. Marked differences in PPAR-γ abundance and distribution were observed, suggesting tissue-specific responses. Analysis of PPAR-γ effects on DNA synthesis, formation of preneoplastic lesions, and activation of MAPK signaling in proximal and distal colonic epithelial cells in vivo indicates that PPAR-γ regulates both tissue-specific and common responses within the proximal and distal colon. Three major functional cohorts of PPAR-γ target genes were identified by genomic profiling of isolated colonic epithelial cells: genes that are involved in metabolism, in signaling, and in cellular adhesion and motility. Two subsets of PPAR-γ target genes were differentially expressed in the proximal and distal epithelium. Proximal target genes were primarily involved in metabolic activities, whereas signal transduction, adhesion, and motility targets were more pronounced in the distal colon. Remarkably, those target genes that are differentially expressed in the proximal colon were all induced on activation of PPAR-γ, whereas all target genes that are preferentially expressed in the distal colon were repressed. Our data indicate that PPAR-γ exerts both common and tissue-specific effects in the colon and challenge the general conclusions that PPAR-γ is induced on differentiation of colonic epithelial cells and that this receptor stimulates differentiated function in epithelial cells throughout the colon.

2017 ◽  
Vol 44 (6) ◽  
pp. 2256-2268 ◽  
Author(s):  
Qiuke Hou ◽  
Yongquan Huang ◽  
Shuilian Zhu ◽  
Peiwu Li ◽  
Xinlin Chen ◽  
...  

Background/Aims: Irritable bowel syndrome with diarrhoea (IBS-D) is a chronic, functional bowel disorder characterized by abdominal pain or diarrhoea and altered bowel habits, which correlate with intestinal hyperpermeability. MicroRNAs (miRNAs) are involved in regulating intestinal permeability in IBS-D. However, the role of miRNAs in regulating intestinal permeability and protecting the epithelial barrier remains unclear. Our goals were to (i) identify differential expression of miRNAs and their targets in the distal colon of IBS-D rats; (ii) verify in vitro whether occludin (OCLN) and zonula occludens 1 (ZO1/TJP1) were direct targets of miR-144 and were down-regulated in IBS-D rats; and (iii) determine whether down-regulation of miR-144 in vitro could reverse the pathological hallmarks of intestinal hyperpermeability via targeting OCLN and ZO1. Methods: The IBS-D rat model was established using 4% acetic acid and evaluated by haematoxylin-eosin (HE) staining. The distal colon was obtained in order to perform miRNA microarray analysis and to isolate and culture colonic epithelial cells. When differential expression of miRNA was found, the results were verified by qRT-PCR, and the target genes were further explored by bioinformatics analysis. Correlation analyses were carried out to compare the expression of miRNA and target genes. Then, mutants, miRNA mimics and inhibitors of the target genes were constructed and transfected to colonic epithelial cells. qRT-PCR, western blotting, enzyme-linked immunosorbent assays (ELISAs) and dual-luciferase assays were used to investigate the expression of miR-144 and OCLN, ZO1 in IBS-D rats. Results: There were 8 up-regulated and 18 down-regulated miRNAs identified in the IBS-D rat model. Of these, miR-144 was markedly up-regulated and resulted in the down-regulation of OCLN and ZO1 expression. Overexpression of miR-144 by transfection of miR-144 precursor markedly inhibited the expression of OCLN and ZO1. Further studies confirmed that OCLN and ZO1 were direct targets of miR-144. Additionally, intestinal hyperpermeability was enhanced by miR-144 up-regulation and attenuated by miR-144 down-regulation in IBS-D rat colonic epithelial cells. Moreover, rescue experiments showed that overexpression of OCLN and ZO1 significantly eliminated the inhibitory effect of miR-144, which showed a stronger effect on the attenuation of intestinal hyperpermeability. Conclusion: Up-regulation of miR-144 could promote intestinal hyperpermeability and impair the protective effect of the epithelial barrier by directly targeting OCLN and ZO1. miR-144 is likely a key regulator of intestinal hyperpermeability and could be a potential therapeutic target for IBS-D.


2017 ◽  
Vol 37 (5) ◽  
Author(s):  
Xiaolin Wu ◽  
Xipeng Chen ◽  
Wenxiang Mi ◽  
Tingting Wu ◽  
Qinhua Gu ◽  
...  

Peri-implantitis, which is characterized by dense inflammatory infiltrates and increased osteoclast activity, can lead to alveolar bone destruction and implantation failure. miRNAs participate in the regulation of various inflammatory diseases, such as periodontitis and osteoporosis. Therefore, the present study aimed to investigate the differential expression of miRNAs in canine peri-implantitis and to explore the functions of their target genes. An miRNA sequence analysis was used to identify differentially expressed miRNAs in peri-implantitis. Under the criteria of a fold-change >1.5 and P<0.01, 8 up-regulated and 30 down-regulated miRNAs were selected for predictions of target genes and their biological functions. Based on the results of Gene Ontology (GO) and KEGG pathway analyses, these miRNAs may fine-tune the inflammatory process in peri-implantitis through an intricate mechanism. The results of quantitative real-time PCR (qRT-PCR) revealed that let-7g, miR-27a, and miR-145 may play important roles in peri-implantitis and are worth further investigation. The results of the present study provide insights into the potential biological effects of the differentially expressed miRNAs, and specific enrichment of target genes involved in the mitogen-activated protein kinase (MAPK) signaling pathway was observed. These findings highlight the intricate and specific roles of miRNAs in inflammation and osteoclastogenesis, both of which are key aspects of peri-implantitis, and thus may contribute to future investigations of the etiology, underlying mechanism, and treatment of peri-implantitis.


2020 ◽  
Author(s):  
Tao Zhong ◽  
Cheng Wang ◽  
Jiangtao Hu ◽  
Xiaoyong Chen ◽  
Lili Niu ◽  
...  

Abstract Background: Rumen is an important digestive organ of ruminant. From fetal to adult stage, the morphology, structure and function of rumen have changed significantly. But the intrinsic genetic regulation is still limited. We previously reported a genome-wide expression profile of miRNAs in prenatal goat rumens. In the present study, we rejoined analyzed the transcriptomes of rumen miRNAs during prenatal (E60 and E135) and postnatal (D30 and D150) stages.Results: A total of 66 differentially expressed miRNAs (DEMs) were identified in the rumen tissues from D30 and D150 goats. Of these, 17 DEMs were consistently highly expressed in the rumens at the preweaning stages (E60, E135 and D30), while down-regulated at D150. Noteworthy, annotation analysis revealed that the target genes regulated by the DEMs were mainly enriched in MAPK signaling pathway, Jak-STAT signaling pathway and Ras signaling pathway. Interestingly, the expression of miR-148a-3p was significantly high in the embryonic stage and down-regulated at D150. The potential binding sites between miR-148a-3p and QKI were predicted by the TargetScan and verified by the dual luciferase report assay. The co-localization of miR-148a-3p and QKI was observed not in intestinal tracts but in rumen tissues by in situ hybridization. Moreover, the expression of miR-148a-3p in the epithelium was significantly higher than that in the other layers, suggesting that miR-148a-3p involve in the development of rumen epithelial cells by targeting QKI. Subsequently, miR-148a-3p inhibitor was found to induce the proliferation of GES-1 cells.Conclusions: Taken together, these results identified the DEMs involved in the development of rumen and provided an insight into the regulation mechanism of goat rumens during development.


Animals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1417
Author(s):  
Chuan Li ◽  
Ting Xiong ◽  
Mingfang Zhou ◽  
Lei Wan ◽  
Suwang Xi ◽  
...  

Poultry skeletal muscle provides high quality protein for humans. Study of the genetic mechanisms during duck skeletal muscle development contribute to future duck breeding and meat production. In the current study, three breast muscle samples from Shan Ma ducks at embryonic day 13 (E13) and E19 were collected, respectively. We detected microRNA (miRNA) expression using high throughput sequencing following bioinformatic analysis. qRT-PCR validated the reliability of sequencing results. We also identified target prediction results using the luciferase reporter assay. A total of 812 known miRNAs and 279 novel miRNAs were detected in six samples; as a result, 61 up-regulated and 48 down-regulated differentially expressed miRNAs were identified between E13 and E19 (|log2 fold change| ≥ 1 and p ≤ 0.05). Enrichment analysis showed that target genes of the differentially expressed miRNAs were enriched on many muscle development-related gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, especially mitogen-activated protein kinase (MAPK) signaling pathways. An interaction network was constructed using the target genes of the differentially expressed miRNAs. These results complement the current duck miRNA database and offer several miRNA candidates for future studies of skeletal muscle development in the duck.


2019 ◽  
Author(s):  
Haisheng Ding ◽  
Min Liu ◽  
Changfan Zhou ◽  
Xiangbin You ◽  
Tao Su ◽  
...  

Abstract Background: MicroRNAs (miRNAs) are small non-coding RNAs playing vital roles in regulating posttranscriptional gene expression. Elucidating the expression regulation of miRNAs underlying pig testis development will contribute to a better understanding of boar fertility and spermatogenesis. Results: In this study, miRNA expression profile was investigated in testes of Duroc and Meishan boars at 20, 75, and 270 days of age by high-throughput sequencing. Forty-five differentially expressed miRNAs were identified from testes of Duroc and Meishan boars before and after puberty. Integrated analysis of miRNA and mRNA profiles predicted many miRNA-mRNA pairs. Gene ontology and biological pathway analyses revealed that predicted target genes of ssc-mir-423-5p, ssc-mir-34c, ssc-mir-107, ssc-165 mir-196b-5p, ssc-mir-92a, ssc-mir-320, ssc-mir-10a-5p, and ssc-mir-181b were involved in sexual reproduction, male gamete generation, and spermatogenesis, and GnRH, Wnt, and MAPK signaling pathway. Four significantly differentially expressed miRNAs and their predicted target genes were validated by quantitative real-time polymerase chain reaction, and phospholipase C beta 1 ( PLCβ1) gene was verified to be a target of ssc-mir-423-5p . Conclusions: This study provides an insight into the functional roles of miRNAs in testis development and spermatogenesis and offers useful resources for understanding differences in sexual function development caused by the change in miRNAs expression between Duroc and Meishan boars.


BMC Biology ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Derek Wong ◽  
Lisa Sogerer ◽  
Samantha S. Lee ◽  
Victor Wong ◽  
Amy Lum ◽  
...  

Abstract Background Aberrations in Capicua (CIC) have recently been implicated as a negative prognostic factor in a multitude of cancer types through the derepression of targets downstream of the mitogen-activated protein kinase (MAPK) signaling cascade, such as oncogenic E26 transformation-specific (ETS) transcription factors. The Ataxin-family protein ATXN1L has previously been reported to interact with CIC in both developmental and disease contexts to facilitate the repression of CIC target genes and promote the post-translational stability of CIC. However, little is known about the mechanisms at the base of ATXN1L-mediated CIC post-translational stability. Results Functional in vitro studies utilizing ATXN1LKO human cell lines revealed that loss of ATXN1L leads to the accumulation of polyubiquitinated CIC protein, promoting its degradation through the proteasome. Although transcriptomic signatures of ATXN1LKO cell lines indicated upregulation of the mitogen-activated protein kinase pathway, ERK activity was found to contribute to CIC function but not stability. Degradation of CIC protein following loss of ATXN1L was instead observed to be mediated by the E3 ubiquitin ligase TRIM25 which was further validated using glioma-derived cell lines and the TCGA breast carcinoma and liver hepatocellular carcinoma cohorts. Conclusions The post-translational regulation of CIC through ATXN1L and TRIM25 independent of ERK activity suggests that the regulation of CIC stability and function is more intricate than previously appreciated and involves several independent pathways. As CIC status has become a prognostic factor in several cancer types, further knowledge into the mechanisms which govern CIC stability and function may prove useful for future therapeutic approaches.


BMC Genomics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Haisheng Ding ◽  
Min Liu ◽  
Changfan Zhou ◽  
Xiangbin You ◽  
Tao Su ◽  
...  

Abstract Background MicroRNAs (miRNAs) are small non-coding RNAs playing vital roles in regulating posttranscriptional gene expression. Elucidating the expression regulation of miRNAs underlying pig testis development will contribute to a better understanding of boar fertility and spermatogenesis. Results In this study, miRNA expression profile was investigated in testes of Duroc and Meishan boars at 20, 75, and 270 days of age by high-throughput sequencing. Forty-five differentially expressed miRNAs were identified from testes of Duroc and Meishan boars before and after puberty. Integrated analysis of miRNA and mRNA profiles predicted many miRNA-mRNA pairs. Gene ontology and biological pathway analyses revealed that predicted target genes of ssc-mir-423-5p, ssc-mir-34c, ssc-mir-107, ssc-mir-196b-5p, ssc-mir-92a, ssc-mir-320, ssc-mir-10a-5p, and ssc-mir-181b were involved in sexual reproduction, male gamete generation, and spermatogenesis, and GnRH, Wnt, and MAPK signaling pathway. Four significantly differentially expressed miRNAs and their predicted target genes were validated by quantitative real-time polymerase chain reaction, and phospholipase C beta 1 (PLCβ1) gene was verified to be a target of ssc-mir-423-5p. Conclusions This study provides an insight into the functional roles of miRNAs in testis development and spermatogenesis and offers useful resources for understanding differences in sexual function development caused by the change in miRNAs expression between Duroc and Meishan boars.


2010 ◽  
Vol 22 (1) ◽  
pp. 281
Author(s):  
D. Salilew-Wondim ◽  
N. Ghanem ◽  
M. Hoelker ◽  
F. Rings ◽  
C. Phatsara ◽  
...  

This experiment aimed to investigate the diestrus transcriptome dynamics of endometrium that resulted in calf delivery or no pregnancy after embryo transfer. Endometrium biopsies were collected from Simmental cyclic heifers at Days 7 and 14 of estrus cycle. On the next cycle, in vivo-produced Day 7 blastocysts were transferred to all animals at Day 7 of estrous cycle. Following pregnancy diagnosis, the endometrial biopsies collected at Day 7 and 14 were categorized based on the pregnancy success. Those endometrial biopsies collected from heifers that subsequently delivered a calf were assigned to the calf-delivery group, and those collected from heifers that did not conceive were assigned to the no-pregnancy group. The endometrial temporal transcriptome profile was compared between Days 7 and 14 in both heifer groups. Total RNA was isolated from each sample in triplicate. Two rounds of RNA amplification were performed using MEGAscript® T7 Kit (Ambion, Inc., Austin, TX, USA) and GeneChip® IVT Labeling Kit (Affymetrix, Inc., Santa Clara, CA, USA), respectively. Following fragmentation, biotin-labeled cRNA samples were hybridized to Affymetrix bovine gene chip array. The microarray data normalization and background correction were performed using GCRMA, and the differentially expressed genes (DEG) (fold change >2,P < 0.05, FDR < 0.3) were identified using LIMMA written on R package integrated with Bioconductor. The result showed that in the calf-delivery group, there were 1867 DEG, among which 1015 and 852 were up- and down-regulated, respectively, in Day 7 compared with Day 14 of the estrous cycle. Some of those genes are believed to be involved in reproductive system development and function (F3, PTGER2, PTGER4, MFGE8, PTGS2, and TDGF1), embryonic development (ALDH1A1,ALDH1A3, FGF2, TGFBR2, PDGFB, and TGFBR2), and nervous system development and function (CYP3A4, CYP3A4, HSD17B4, FOXA2, MET, TDGF, WNT11). The bioinformatic analysis using KEGG revealed that those DEG were classified into several pathways including the MAPK signaling pathway. On the other hand, in the no-pregnancy group, 254 genes were found to be differentially expressed, of which 160 and 94 were up- and down-regulated, respectively, in Day 7 compared with Day 14 of the estrous cycle. Some of these genes were found to be involved in signal transducer activity (AXIN2, AGTR1, MAPK10, NTRK2, TLR2, DMBT1, IL1RN, CDK5, CHRNE), transferase activity (DGKI, TXNDC6, RPS6KA5, RIOK3, MYLK, CDK5, MET, NTRK2), receptor activity (MET,AGTR1, NTRK2, TLR2, DMBT1, CHRNE), regulation of transcription (FOS, ELF1, BHLHB2,ATF3, HOXA11), signal transduction (TLR2, AGTR1, FCNB, DGK, NOTCH2, ADAM9, PLEK), and transcription regulator activity (BHLHB2, FOS, ELF1,ATF3, HOXA11). Those DEG were found to be involved in different pathways including the focal adhesion pathway. In conclusion, the result of the current study revealed a remarkable transcriptome dynamics between Days 7 and 14 of the estrous cycle in cows resulted in calf delivery compared with those that did not support pregnancy.


2005 ◽  
Vol 84 (2) ◽  
pp. 160-165 ◽  
Author(s):  
N.S. Treister ◽  
S.M. Richards ◽  
M.J. Lombardi ◽  
P. Rowley ◽  
R.V. Jensen ◽  
...  

Sex-related differences exist in the structure and function of the major glands in a variety of species. Moreover, many of these variations appear to be unique to each tissue. We hypothesized that this sexual dimorphism is due, at least in part, to gland-specific differences in gene expression between males and females. Glands were collected from male and female BALB/c mice (n = 5/sex/experiment), and total RNA was isolated. Samples were analyzed for differentially expressed mRNAs with CodeLink microarrays, and data were evaluated by GeneSifter. Our results demonstrate that significant (P < 0.05) sex-related differences exist in the expression of numerous genes in the major salivary glands, and many of these differences were tissue-specific. These findings support our hypothesis that sex-related differences in the salivary glands are due, at least in part, to tissue-specific variations in gene expression.


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