ChIP-on-Chip Analysis Identified HLXB9 as a Transcription Factor In Hematopoietic Cells and Alters the Expression of Genes Involved In Cell-Adhesion

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2486-2486
Author(s):  
Sarah Wildenhain ◽  
Christian Ruckert ◽  
Svenja Daschkey ◽  
Martin Dugas ◽  
Julia Hauer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Cell Adhesion ◽  
Hematopoietic Cells ◽  
Promoter Regions ◽  
Altered Gene Expression ◽  
Altered Gene ◽  
On Chip ◽  
Chip Analysis

Abstract Abstract 2486 Infants with t (7;12)/HLXB9-TEL positive Acute Myeloid Leukemia (AML) have an Event-Free Survival (EFS) of 0 % and are characterized by concomitant HLXB9 (MNX1) expression. However, the role of the homeobox protein HLXB9 on hematopoietic cell development remains unknown. Expression profiling of t (7;12) and t (11;X) positive leukemias revealed up-regulation of cell-cell interacting genes in t (7;12) positive leukemia (Wildenhain et al., 2010). Furthermore, no increased expression of HOX-Genes, like HOXA9 and MEIS1, could be observed in t (7;12) positive leukemia compared to t (11;X) positive leukemia. Based on the altered gene expression profile in t (7;12) positive leukemia we investigated the role of HLXB9 as a transcription factor in hematopoietic cells using ChIP-on-chip analysis and its impact on the cellular gene expression pattern using Affymetrix expression arrays. The myeloid cell line HL60 was stable transfected with a CMV-HLXB9 (HL60/HLXB9) expression vector or an empty vector control (HL60/control). Microarray analysis was performed using “Human Gene 1.0 ST Arrays” (Affymetrix) and data from the HL60/HLXB9 cells were normalized to HL60/control cells. ChIP-on-chip analysis was performed using the “SimpleChIP Enzymatic Chromatin IP Kit” (Cell Signaling Technologies). Hybridisation on “385K RefSeq Promoter arrays” and analysis of raw data were performed by NimbleGen using the NimbleScan software. Data were visualized with the SignalMap software. Altered expression analyses as well as enrichment of promoter regions were validated by quantitative RT-PCR. Expression analysis revealed 81 differentially expressed genes, whereof 63 were down-regulated indicating that HLXB9 acts as a transcriptional repressor, as characteristic for homeobox proteins. CLEC5A, normally expressed in mature myeloid cells, is the highest differentially repressed gene. Further, we identified several differentially expressed genes which interfere in cell-adhesion and/or angiogenesis (e.g. IL8, ZYX, SELL, SPP1, EMILIN2). Western blot analysis of nuclear extracts confirmed the translocation of HLXB9 into the nucleus. ChIP-on-chip analysis revealed binding of HLXB9 to several promoter regions, among them the promoters of ZYX and IL8. Binding of HLXB9 to those promoters results in a decreased gene expression.These data strengthens the hypothesis, that HLXB9 plays a major role in cell adhesion and/or cell interactions. Further we observed increased expression of the adhesion molecule CD11b, when culturing HL60/HLXB9 cells in All-Trans Retinoic Acid (ATRA) containing medium in contrast to HL60/control cells. In summary, this study shows that HLXB9 acts as a transcription factor in hematopoietic cells and has a repressive function on gene expression. HLXB9 target genes regulate cell-adhesion and angiogenesis. This study provides the first molecular results of HLXB9 function in hematopoietic cells and supports the previously published data showing the importance on altered gene expression of cell-cell interacting genes in the pathogenesis of t (7;12) positive leukemia. Disclosures: No relevant conflicts of interest to declare.

Microarray Analysis of Altered Gene Expression and the Role of ATF3 in HK-2 Cells Treated with Hemin

Renal Failure ◽  
2013 ◽  
Vol 35 (5) ◽  
pp. 624-632
Author(s):  
Jingwen Wang ◽  
Dewen Wang ◽  
Yang Li ◽  
Yabing Gao ◽  
Shaoxia Wang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Microarray Analysis ◽  
Altered Gene Expression ◽  
Altered Gene

scholarly journals Insight into GATA1 transcriptional activity through interrogation of cis elements disrupted in human erythroid disorders

2016 ◽  
Vol 113 (16) ◽  
pp. 4434-4439 ◽  
Author(s):  
Aoi Wakabayashi ◽  
Jacob C. Ulirsch ◽  
Leif S. Ludwig ◽  
Claudia Fiorini ◽  
Makiko Yasuda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Transcriptional Activity ◽  
Regulatory Elements ◽  
Binding Motif ◽  
Targeted Disruption ◽  
Altered Gene Expression ◽  
Whole Exome ◽  
Altered Gene ◽  
Insight Into

Whole-exome sequencing has been incredibly successful in identifying causal genetic variants and has revealed a number of novel genes associated with blood and other diseases. One limitation of this approach is that it overlooks mutations in noncoding regulatory elements. Furthermore, the mechanisms by which mutations in transcriptional cis-regulatory elements result in disease remain poorly understood. Here we used CRISPR/Cas9 genome editing to interrogate three such elements harboring mutations in human erythroid disorders, which in all cases are predicted to disrupt a canonical binding motif for the hematopoietic transcription factor GATA1. Deletions of as few as two to four nucleotides resulted in a substantial decrease (>80%) in target gene expression. Isolated deletions of the canonical GATA1 binding motif completely abrogated binding of the cofactor TAL1, which binds to a separate motif. Having verified the functionality of these three GATA1 motifs, we demonstrate strong evolutionary conservation of GATA1 motifs in regulatory elements proximal to other genes implicated in erythroid disorders, and show that targeted disruption of such elements results in altered gene expression. By modeling transcription factor binding patterns, we show that multiple transcription factors are associated with erythroid gene expression, and have created predictive maps modeling putative disruptions of their binding sites at key regulatory elements. Our study provides insight into GATA1 transcriptional activity and may prove a useful resource for investigating the pathogenicity of noncoding variants in human erythroid disorders.

scholarly journals Altered gene expression patterns in muscle ring finger 1 null mice during denervation- and dexamethasone-induced muscle atrophy

2013 ◽  
Vol 45 (23) ◽  
pp. 1168-1185 ◽  
Author(s):  
J. David Furlow ◽  
Monica L. Watson ◽  
David S. Waddell ◽  
Eric S. Neff ◽  
Leslie M. Baehr ◽  
...  
Keyword(s):  
Gene Expression ◽  
Muscle Atrophy ◽  
Intracellular Signaling ◽  
Expression Patterns ◽  
Ring Finger ◽  
Altered Gene Expression ◽  
Catabolic State ◽  
Altered Gene ◽  
Multiple Conditions

Muscle atrophy can result from inactivity or unloading on one hand or the induction of a catabolic state on the other. Muscle-specific ring finger 1 (MuRF1), a member of the tripartite motif family of E3 ubiquitin ligases, is an essential mediator of multiple conditions inducing muscle atrophy. While most studies have focused on the role of MuRF1 in protein degradation, the protein may have other roles in regulating skeletal muscle mass and metabolism. We therefore systematically evaluated the effect of MuRF1 on gene expression during denervation and dexamethasone-induced atrophy. We find that the lack of MuRF1 leads to few differences in control animals, but there were several significant differences in specific sets of genes upon denervation- and dexamethasone-induced atrophy. For example, during denervation, MuRF1 knockout mice showed delayed repression of metabolic and structural genes and blunted induction of genes associated with the neuromuscular junction. In the latter case, this pattern correlates with blunted HDAC4 and myogenin upregulation. Lack of MuRF1 caused fewer changes in the dexamethasone-induced atrophy program, but certain genes involved in fat metabolism and intracellular signaling were affected. Our results demonstrate a new role for MuRF1 in influencing gene expression in two important models of muscle atrophy.

scholarly journals Putative positive role of inflammatory genes in fat deposition supported by altered gene expression in purified human adipocytes and preadipocytes from lean and obese adipose tissues

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Sang-Hyeop Lee ◽  
Nak-Hyeon Choi ◽  
In-Uk Koh ◽  
Bong-Jo Kim ◽  
Song Lee ◽  
...  
Keyword(s):  
Gene Expression ◽  
Inflammatory Responses ◽  
Low Grade ◽  
Positive Role ◽  
Inflammatory Genes ◽  
Altered Gene Expression ◽  
Tnf Α ◽  
Altered Gene ◽  
Geo Database

Abstract Background Obesity is a chronic low-grade inflammatory disease that is generally characterized by enhanced inflammation in obese adipose tissue (AT). Here, we investigated alterations in gene expression between lean and obese conditions using mRNA-Seq data derived from human purified adipocytes (ACs) and preadipocytes (preACs). Results Total mRNA-seq data were generated with 27 AC and 21 preAC samples purified from human visceral AT collected during resection surgery in cancer patients, where the samples were classified into lean and obese categories by BMI > 25 kg/m2. We defined four classes of differentially expressed genes (DEGs) by comparing gene expression between (1) lean and obese ACs, (2) lean and obese preACs, (3) lean ACs and lean preACs, and 4) obese ACs and obese preACs. Based on an analysis of comparison 1, numerous canonical obesity-related genes, particularly inflammatory genes including IL-6, TNF-α and IL-1β, i.e., the genes that are expected to be upregulated in obesity conditions, were found to be expressed at significantly lower levels in obese ACs than in lean ACs. In contrast, some inflammatory genes were found to be expressed at higher levels in obese preACs than lean preACs in the analysis of comparison 2. The analysis of comparisons 3 and 4 showed that inflammatory gene classes were expressed at higher levels in differentiated ACs than undifferentiated preACs under both lean and obese conditions; however, the degree of upregulation was significantly greater for lean than for obese conditions. We validated our observations using previously published microarray transcriptome data deposited in the GEO database (GSE80654). Conclusions Taken together, our analyses suggest that inflammatory genes are expressed at lower levels in obese ACs than in lean ACs because lean adipogenesis involves even greater enhancement of inflammatory responses than does obese adipogenesis.

Altered gene expression patterns in intrauterine growth restriction: Potential role of hypoxia

2007 ◽  
Vol 196 (1) ◽  
pp. 70.e1-70.e6 ◽  
Author(s):  
Cathal McCarthy ◽  
Finbarr E. Cotter ◽  
Suzanne McElwaine ◽  
Anne Twomey ◽  
Eoghan E. Mooney ◽  
...  
Keyword(s):  
Gene Expression ◽  
Intrauterine Growth Restriction ◽  
Potential Role ◽  
Expression Patterns ◽  
Growth Restriction ◽  
Gene Expression Patterns ◽  
Intrauterine Growth ◽  
Altered Gene Expression ◽  
Altered Gene
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