Tristetraprolin (TTP) is a tandem CCCH zinc finger protein that was identified through its rapid induction by mitogens in fibroblasts. Studies of TTP-deficient mice, and cells derived from them, showed that TTP could bind to certain AU-rich elements in mRNAs, leading to increases in the rates of mRNA deadenylation and destruction. Known physiological target
Novel mRNA targets for tristetraprolin (TTP) identified by global analysis of stabilized transcripts in TTP-deficient fibroblasts.
Cell line
View SamplesToll like receptor 4 (TLR4), an innate immunity gene, is involved in responses to several pulmonary agonists including endotoxin (LPS; Poltorak et al.,1998), ozone (O3 ,Kleeberger et. al., 2001), Pseudomonas aeruginosa (Faure et al, 2004), and hyperoxia (Zhang et al, 2005). TLR4 appears to partially mediate the response to LPS- and O3-induced lung injury, however, TLR4 is protective for prevention of injury in Pseudomonas aeruginosa infection and against acute lung injury (hyperoxia). The mechanism behind this protection is unclear. We previously demonstrated that TLR4 was also protective against BHT-induced chronic inflammation and tumor promotion (Bauer et al, 2005). C.C3H-Tlr4Lps-d (BALBLps-d) mice, congenic for a 10 cM region of C3H/HeJ chromosome 4 that contains Tlr4 (Vogel et al, 1994), have a missence mutation that renders TLR4 dysfunctional. The Tlr4 mutation likely abrogates signaling by disrupting a direct point of contact with other signaling molecules (Akira S, Takeda K. Toll-like receptor signalling. Nat Rev Immunol 2004;4(7):499-511.). Bronchoalveolar lavage fluid (BALF) alveolar macrophages, lymphocytes, and total protein content were significantly elevated in BALBLps-d mice compared to BALB/c (BALB; Tlr4 sufficient) mice following chronic BHT (Bauer et al., 2005). BALBLps-d mice also had a significant increase in tumor multiplicity (60%) over that of BALB mice in response to an MCA/BHT tumor promotion protocol. While this was the first model to demonstrate a protective role for TLR4 in chronic lung inflammation and tumorigenesis, the downstream mechanism regulating this protective response remains unknown. Using Affymetrix microarray analysis followed by GeneSpring and Ingenuity pathway analyses, we herein identified known and novel downstream pathways and their interactions that may be involved in the protective mechanism elicited by TLR4. We therefore hypothesize that these pathways and interactions amongst the genes identified during the tumor promotion/chronic inflammation stage are in part influencing the differential strain response observed during tumorigenesis.
Transcriptomic analysis of pathways regulated by toll-like receptor 4 in a murine model of chronic pulmonary inflammation and carcinogenesis.
No sample metadata fields
View SamplesRegulation of gene expression is integral to the development and survival of all organisms. Transcription begins with the assembly of a pre-initiation complex at the gene promoter, followed by initiation of RNA synthesis and the transition to productive elongation. In many cases, recruitment of RNA polymerase II (Pol II) to a promoter is necessary and sufficient for activation of gene. However, there are a few notable exceptions to this paradigm, including heat shock genes and several proto-oncogenes, whose expression is attenuated by regulated stalling of polymerase elongation within the promoter-proximal region. To determine the importance of polymerase stalling for transcription regulation, we performed a genome-wide search for Drosophila genes with promoter-proximally stalled Pol II. Our data reveal that stalling is widespread, occurring at hundreds of genes that respond to stimuli and developmental signals, indicating a role for regulation of polymerase elongation in the transcriptional responses to dynamic environmental and developmental cues.
RNA polymerase is poised for activation across the genome.
No sample metadata fields
View SamplesThe role of estrogen and testosterone in the regulation of gene expression in the proximal reproductive tract is not completely understood. To address this question, mice were treated with testosterone or estradiol and RNA from the efferent ducts and caput epididymis was processed and hybridized to Affymetrix MOE 430 2.0 microarrays. Analysis of array output identified probe sets in each tissue with altered levels in hormone treated versus control animals. Hormone treatment efficacy was confirmed by determination of serum hormone levels pre- and post-treatment and observed changes in transcript levels of previously reported hormone-responsive genes. Tissue-specific hormone sensitivity was observed with 2867 and 3197 probe sets changing significantly in the efferent ducts after estrogen and testosterone treatment, respectively. In the caput epididymis, 117 and 268 probe sets changed after estrogen and testosterone treatment, respectively, demonstrating a greater response to hormone in the efferent ducts than the caput epididymis. Transcripts sharing similar profiles in the intact and hormone-treated animals compared with castrated controls were also identified. Ontological analysis of probe sets revealed a significant number of hormone-regulated transcripts encode proteins associated with lipid metabolism, transcription and steroid metabolism in both tissues. Real-time RT-PCR was employed to confirm array data and investigate other potential hormone-responsive regulators of proximal reproductive tract function. The results of this work reveal previously unknown responses to estrogen in the caput epididymis and to testosterone in the efferent ducts as well as tissue specific hormone sensitivity in the proximal reproductive tract.
Regulation of gene expression by estrogen and testosterone in the proximal mouse reproductive tract.
Sex, Specimen part, Treatment
View SamplesExpession data from L1-L2 stage nematodes (C. elegans), wild type and four mutants (alg-1, zfp-1, rde-4, lin-35).
RNA interference and retinoblastoma-related genes are required for repression of endogenous siRNA targets in Caenorhabditis elegans.
No sample metadata fields
View SamplesWIN 18,446/RA treatment of neonatal mice was used to synchronize the initial wave of spermatogenesis and identify novel messages expressed within either germ or Sertoli cells as spermatogonia enter meiosis.
Riding the spermatogenic wave: profiling gene expression within neonatal germ and sertoli cells during a synchronized initial wave of spermatogenesis in mice.
Specimen part
View SamplesMurine testis developmental time course created from tissue samples collected from birth through adulthood and hybridized to MGU74v2 A, B, and C chips in duplicate
The murine testicular transcriptome: characterizing gene expression in the testis during the progression of spermatogenesis.
No sample metadata fields
View SamplesTime course of gene expression in the murine embryonic testis from the time of the indifferent gonad (11.5dpc) to birth (18.5dpc)
Profiling gene expression during the differentiation and development of the murine embryonic gonad.
No sample metadata fields
View SamplesTime course of gene expression in the murine embryonic ovary from the time of the indifferent gonad (11.5dpc) to birth (18.5dpc)
Profiling gene expression during the differentiation and development of the murine embryonic gonad.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Profiling gene expression during the differentiation and development of the murine embryonic gonad.
No sample metadata fields
View Samples