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Results for “Untranslated Regions”

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At least 19 recordsLinked to original sources

PubMed2003

[Cloning and identification of 5'-untranslated region (UTR) and 3'-untranslated region of neutrophil gelatinase-associated lipocalin (NGAL) gene from esophageal carcinoma cell line SHEEC].

BACKGROUND & OBJECTIVE: Neutrophil gelatinase-associated lipocalin (NGAL) was a novel member of the lipocalin family. The authors previously found that NGAL was overexpressed in the progress of malignant transformation from human immortalized esophageal epithelial cell line SHEE to esophageal carcinoma cell line SHEEC. However, the regulation mechanism of NGAL overexpression was not known. The objective of this study was to clone 5'-untranslated region(5'-UTR) and 3'untranslated region (3'-UTR) of NGAL in SHEEC and to analyze their structural characters. METHODS: 5'-UTR and 3'-UTR of NGAL were cloned from SHEEC using rapid amplification of cDNA ends(RACE). After sequencing the alignment of their nucleotides was analyzed by BLAST database of NCBI and the potential cis-acting elements in the 3'-UTR were identified by computer analysis. RESULTS: The authors cloned and sequenced 69 bp 5'-UTR and 147 bp 3'-UTR of NGAL gene on the basis of the previous works and did not find any base pair mutation. CONCLUSION: NGAL gene from SHEEC had the entire 5'-UTR and 3'-UTR.

3' Untranslated Regions↗

PubMed2006

Regulation of gene expression by alternative untranslated regions.

The untranslated regions of mRNAs can determine gene expression by influencing mRNA stability and translational efficiency. Recent reports show that gene expression can be regulated by the differential use of alternative untranslated regions. Tissue-specific expression of transcripts that have different untranslated regions (UTRs) can control protein expression enabling developmental, physiological and pathological regulation. Several examples of alternative UTRs have been characterized, including those found in AXIN2, FGF1 and BRCA1. Results from bioinformatics studies indicate that this mechanism is more common than previously appreciated.

3' Untranslated Regions↗

PubMed2005

Differential mRNA stability to endogenous ribonucleases of the coding region and 3' untranslated regions of wheat (Triticum aestivum L.) manganese superoxide dismutase genes.

The sequences of the 3' untranslated region (UTR) of the manganese superoxide dismutase (MnSOD) genes in wheat (Triticum aestivum) were found to be quite variable with different predicted thermostabilities. The degradation rates of the 3' UTR variants and the coding region were measured following exposure to endogenous nucleases. The degradation rates of the 3' UTR variants for 15 min were not significantly different, meaning the degradation rates of the 3' UTR variants were not directly related to the thermostabilities. However, the degradation rate of the coding region was significantly faster than those of the 3' UTR variants. Further investigation revealed the coding region seemed to have specific sites for degradation, indicating a possibility of increasing MnSOD expression by the degradation site alteration.

3' Untranslated Regions↗

PubMed1992

Sequence of the gamma 2b membrane 3' untranslated region: polya site determination and comparison to the gamma 2a membrane 3' untranslated region.

We present here the nucleotide sequence of the gamma 2b membrane 3' untranslated region as well as approximately 443 nucleotides of 3' flanking sequence. Although this region contains two potential polyadenylation hexanucleotides AATAAA (located 1328 and 1407 nucleotides downstream of the last membrane exon), it appears that only the first site directs polyadenylation of the mature mRNA. The first AATAAA is followed by several sequences which may influence its relative strength: the region downstream of this AATAAA is 44% T-rich and contains a pair of CAYTG sequences (4/5 match) which overlap two sequences which have a 6/8 match to the sequence YGTGTTYY. These sequences have been found in proximity to a large number of 3' ends [Gil and Proudfoot, Cell 49, 399-406 (1987); McLauchlan et al., Nucl. Acids Res. 13, 1347-1368. (1985); Berget, Nature 309, 179-182 (1984)]. The AATAAA site at position 1407 is not flanked by a T- or GT-rich sequence and is followed by a single CAYTG sequence (4/5 match) and a single YGTGTTYY sequence (6/8 match). The region downstream of the second AATAAA site also contains a sequence which has an 8/12 match with a sequence found in all heavy chain secreted 3' untranslated regions [Kobrin et al., Molec. Cell. Biol. 6, 1687-1697 (1986)]. Consistent with sequence comparisons between other regions of these two genes, the gamma 2b sequence has striking homology with the gamma 2a 3' untranslated region. A notable difference between gamma 2b and gamma 2a is the absence of an extensive array of GAA, GA, GGAA, and GGA repeats from the gamma 2b sequence. The GA repeats are postulated to form a stem loop structure in the gamma 2a 3' untranslated region; gamma 2b then would be missing the 5' half of the stem. Interestingly, neither the gamma 2b nor the gamma 2a 3' untranslated regions show large homologies to the mu, delta, gamma 3, or the alpha membrane 3' untranslated regions.

Animals↗

PubMed2006

Comparative analysis of hepatitis C virus phylogenies from coding and non-coding regions: the 5' untranslated region (UTR) fails to classify subtypes.

BACKGROUND: The duration of treatment for HCV infection is partly indicated by the genotype of the virus. For studies of disease transmission, vaccine design, and surveillance for novel variants, subtype-level classification is also needed. This study used the Shimodaira-Hasegawa test and related statistical techniques to compare phylogenetic trees obtained from coding and non-coding regions of a whole-genome alignment for the reliability of subtyping in different regions. RESULTS: Different regions of the HCV genome yield inconsistent phylogenies, which can lead to erroneous conclusions about classification of a given infection. In particular, the highly conserved 5' untranslated region (UTR) yields phylogenetic trees with topologies that differ from the HCV polyprotein and complete genome phylogenies. Phylogenetic trees from the NS5B gene reliably cluster related subtypes, and yield topologies consistent with those of the whole genome and polyprotein. CONCLUSION: These results extend those from previous studies and indicate that, unlike the NS5B gene, the 5' UTR contains insufficient variation to resolve HCV classifications to the level of viral subtype, and fails to distinguish genotypes reliably. Use of the 5' UTR for clinical tests to characterize HCV infection should be replaced by a subtype-informative test.

5' Untranslated Regions↗

PubMed2001

Polymorphisms/mutations of TCR-zeta-chain promoter and 3' untranslated region and selective expression of TCR zeta-chain with an alternatively spliced 3' untranslated region in patients with systemic lupus erythematosus.

A vast majority of systemic lupus erythematosus (SLE) patients display decreased expression of TCR zeta-chain mRNA, a critical signaling molecule implicated in the selection of the TCR repertoire and in the prevention of autoimmunity. To identify the molecular mechanisms involved in the downregulation of TCR zeta-chain transcripts in SLE T cells, we investigated the possibility of polymorphisms/mutations in the promoter and the 3' untranslated region. PCR, cloning and sequence analysis of the promoter region from the genomic DNA showed significantly higher number of polymorphisms in SLE T cells compared to non-SLE control subjects (P = 0.044). Promoter sequence was also analysed from granulocytes to delineate the possibility of somatic mutations in activated SLE T cells. Promoter polymorphisms were significantly higher in granulocytes of SLE patients compared to non-SLE controls (P = 0.048), suggesting that these polymorphisms were of genomic origin. Nucleotide analysis of the promoter sequence revealed a -76T insertion compared to the published sequence, in all of the SLE samples and controls. RT-PCR analysis of the TCR zeta-chain 3' untranslated region showed a 344 bp product in addition to the expected 906 bp product. Cloning and sequence analysis of the 344 bp product indicated that it is an alternatively spliced form with both splicing donor and acceptor sites, resulting in deletion of nucleotides 672-1233 of TCR zeta-chain mRNA. Unlike the nomal TCR zeta-chain, the expression of TCR zeta-chain with the alternatively spliced 344 bp 3' untranslated region was higher in SLE T cells compared to non-SLE controls. The number of mutations/polymorphisms in the 906 bp TCR zeta-chain 3' untranslated region were significantly higher in SLE T cells compared to non-SLE subjects (P = 0.032). Frequent mutations/polymorphisms and aberrant splicing of the downstream 3' untranslated region may affect the stability and/or transport of TCR zeta-chain mRNA, leading to its downregulation in SLE T cells.

3' Untranslated Regions↗

PubMed1993

Ca2+ ionophore A23187-dependent stabilization of granulocyte-macrophage colony-stimulating factor messenger RNA in murine thymoma EL-4 cells is mediated through two distinct regions in the 3'-untranslated region.

We analyze the role of the Ca2+ ionophore A23187 in the induction of GM-CSF mRNA expression in EL-4 thymoma cells. Northern analysis shows that A23187 increases the half-life of GM-CSF mRNA. To identify potential Ca2+ response elements in the GM-CSF mRNA, we produced stable transfectants containing pRSV-CAT (EL-4cat) or hybrid constructs in which most of the GM-CSF 3'-untranslated region (EL-4gm) or the adenosine-uridine boxes alone (EL-4au) were placed in a downstream position from the CAT coding region. A23187 induces a 4.4-fold increase in CAT activity in EL-4cat cells and a 210-fold and 48-fold increase in CAT activity in EL-4gm and EL-4au cells, respectively. Actinomycin D chase experiments in transfected cells demonstrate that A23187 increases the half-life of CAT mRNA from 15 min to 3 h in EL-4au cells and more than 3 h in EL-4gm cells, suggesting that the effect of Ca2+ is mediated predominantly by the adenosine-uridine boxes with a smaller contribution from upstream regions. To map these upstream regions, we transfected cells with constructs containing mutations of the 3'-untranslated region. With two of these mutations, corresponding to a region located about 160 bases upstream of the adenosine-uridine boxes, CAT activity was induced only 50-fold compared to 200-fold in EL-4gm cells. These data indicate that two regions within the GM-CSF 3'-untranslated region interact to modulate Ca2+ effects on GM-CSF mRNA half-life.

Animals↗

PubMed1997

Co-operation of the 5' and 3' untranslated regions of ornithine decarboxylase mRNA and inhibitory role of its 3' untranslated region in regulating the translational efficiency of hybrid RNA species via cellular factor.

The 5' untranslated region (UTR) has an inhibitory role in the translatability of ornithine decarboxylase (ODC) mRNA and of hybrid mRNA species, whereas the ODC 3' UTR causes a partial release of this inhibition. We designed experiments to explore whether the co-operation between ODC 5' UTR and 3' UTR in the translational regulation is due to a direct interaction of those sequences or whether it is mediated by their interaction with cellular factor(s). We stably transfected Chinese hamster ovary (CHO)-K1 cells and transiently transfected COS-1 cells with expression vectors carrying different chimaeric DNAs having the luciferase (LUC) coding sequence as reporter gene, the ODC 5' UTR or the ODC 3' UTR, or both, in the appropriate positions. We compared the results obtained by assaying the LUC activities of both transfected cell lines with each chimaeric DNA with those observed by translating the hybrid RNAs in a translation system in vitro. When the ODC 3' UTR was present, we observed a partial release of the translation inhibition owing to the ODC 5' UTR only in vivo. The releasing effect was restored in vitro by the addition of cytoplasmic extracts from wild-type CHO-K1 or COS-1 cells, prepared 2 and 8 h after their release from serum starvation. We also observed a partial inhibition of the translatability of the hybrid RNA owing to the presence of the ODC 3' UTR itself; the translational efficiency could be rescued by cell extract from 8 h serum-stimulated cells. The co-operation between the ODC-UTRs might be mediated by factors expressed by cells during particular phases of the cell cycle. Excess copies of the ODC-UTRs, expressed in trans, could compete in binding limited amounts of such regulatory factors and remove them from interaction with the endogenous ODC mRNA. This phenomenon should be reflected by modifications of the kinetics of ODC and/or LUC activities during serum stimulation. The overexpression of the ODC 3' UTR determined an increase in both endogenous ODC activity and LUC activity. Moreover, in the transfectants expressing the hybrid RNA species bearing the ODC 3' UTR the basal ODC activity is higher than that observed in control cells. We suggest that excess copies of the ODC 3' UTR mis-regulate the endogenous ODC translatability, probably by tying up regulatory molecules expressed by cells in limited amounts and sequestering them from the ODC mRNA species they should interact with.

Animals↗

PubMed2001

mRNA localization by a 145-nucleotide region of the c-fos 3'--untranslated region. Links to translation but not stability.

The presence of a localization signal in the 3'-untranslated region of c-fos mRNA was investigated by in situ hybridization and cell fractionation techniques. Cells were transfected with chimeric gene constructs in which the beta-globin coding region was used as a reporter and linked to either its own 3'-untranslated region, the c-fos 3'-untranslated region, or the c-fos 3'-untranslated region containing different deletions. Replacement of the endogenous beta-globin 3'-untranslated region by that from c-fos caused a redistribution of the transcripts so that they were recovered in cytoskeletal-bound polysomes and seen localized in the perinuclear cytoplasm. Deletion of the AU-rich instability region did not affect transcript localization, but removal of a distinct 145-nucleotide region of the 3'-untranslated region abolished it. The prevention of transcript translation by desferrioxamine led to a marked loss of transcript localization, independent of mRNA instability. The data show that the 3'-untranslated region of c-fos mRNA, as c-myc, contains a localization signal, which targets the mRNA to the perinuclear cytoskeleton. We propose that this is important to ensure efficient nuclear import of these key regulatory proteins. mRNA localization by the fos 3'-untranslated region is independent of mRNA instability, and the two are determined by different regulatory elements.

3' Untranslated Regions↗

PubMed1992

Molecular cloning of the mouse S-adenosylmethionine decarboxylase cDNA: specific protein binding to the conserved region of the mRNA 5'-untranslated region.

The nucleotide sequence of a cDNA encoding the proenzyme of mouse S-adenosylmethionine decarboxylase (AdoMetDC) including 257 nucleotides of the 5' untranslated region has been determined. Comparison of the nucleotide sequence of the mouse 5' untranslated region with those of other mammals shows it to be highly conserved. The 52 nucleotides upstream from the translation initiation codon are identical in human, rat, bovine and mouse. The polyamines, spermidine and spermine, have been shown to inhibit AdoMetDC mRNA translation. An RNA gel retardation assay demonstrated that a cytoplasmic extract from mouse brain forms an RNA-protein complex with the completely conserved 5' untranslated sequence and that the complex formation is highly dependent on the presence of spermine. Crosslinking by UV irradiation shows that the complex contains a 39-kDa protein interacting with the 5' untranslated sequence. These data demonstrate spermine-dependent specific protein binding to a highly conserved 5' untranslated region of an mRNA translationally regulated by polyamines.

Adenosylmethionine Decarboxylase↗

PubMed1998

Negative control of the poly(A)-binding protein mRNA translation is mediated by the adenine-rich region of its 5'-untranslated region.

Translation of the mRNA for the poly(A)-binding protein (PABP) may be autoregulated by the binding of PABP to the A-rich segment of its 5'-untranslated region (UTR). To test this hypothesis, we examined the effect of different fragments of the 5'-UTR from human PABP cDNA on the translation of the beta-galactosidase (beta-Gal) reporter gene. Presence of the A-rich sequence from the 5'-UTR of PABP mRNA inhibited expression of the chimeric beta-Gal gene in transfected HeLa cells. The differences in expression of beta-Gal polypeptide was due to the translational repression of beta-Gal mRNA containing the A-rich 5'-UTR of PABP mRNA. The A-rich region of the 5'-UTR located within nucleotides 58-146 of PABP mRNA was sufficient to mediate translational control of this mRNA expression. We also examined the effect of overexpression of PABP mRNA in HeLa cells. The ectopic PABP mRNA without the A-rich 5'-UTR region was translated efficiently, whereas the translation of the endogenous PABP mRNA was substantially inhibited in the transfected cells. In contrast, the ectopic PABP mRNA containing the A-rich 5'-UTR region did not show similar effect on the translation of the endogenous PABP mRNA in these cells. These results suggest that feedback control of mRNA translation is involved in regulating PABP expression in HeLa cells.

5' Untranslated Regions↗

PubMed2000

Inclusion of the hepatic locus control region, an intron, and untranslated region increases and stabilizes hepatic factor IX gene expression in vivo but not in vitro.

We systematically compared human factor IX gene expression from a variety of plasmids containing different cis-regulatory sequences after transfection into different hepatocyte cell lines, or in vivo, after their injection into the livers of mice. Although there was a 1.5- to 2.0-fold variation in gene expression from cultured cells, a 65-fold variation was observed in the in vivo studies. We found that a plasmid containing the apolipoprotein E locus control region (HCR), human alpha1-antitrypsin (hAAT) promoter, hFIX minigene (hFIXmg) sequence including a portion of the first intron (intron A), 3'-untranslated region (3'-UTR), and a bovine growth hormone polyadenylation signal (bpA) produced the highest serum level of human factor IX, reaching 18 microg/ml (normal = 5 microg/ml) 1 day after injection. Although most of the plasmid DNAs resulted in transient gene expression, inclusion of an intron, a polyadenylation signal from either the 1.7-kb 3'-UTR or the 0.3-kb bpA, and the HCR resulted in persistent and therapeutic levels of hFIX gene expression, ranging from 0.5 to 2 microg/ml (10 to 40% of normal) for 225 days (length of experiment). These data underscore the importance of cis sequences for enhancing in vivo hepatic gene expression and reemphasize the lack of correlation of gene expression in tissue culture and in vivo studies.

3' Untranslated Regions↗

PubMed2003

The proximal region of the 3'-untranslated region of cyclooxygenase-2 is recognized by a multimeric protein complex containing HuR, TIA-1, TIAR, and the heterogeneous nuclear ribonucleoprotein U.

Cyclooxygenase-2 (COX-2) is an early response gene induced in renal mesangial cells by interleukin-1beta (IL-1beta). The 3'-untranslated region (3'-UTR) of COX-2 mRNA plays an important role in IL-1beta induction by regulating message stability and translational efficiency. The first 60 nucleotides of the 3'-UTR of COX-2 are highly conserved and contain multiple copies of the regulatory sequence AUUUA. Introduction of the 60-nucleotide sequence into the 3'-UTR of a heterologous reporter gene resulted in a 70% decrease in reporter gene expression. Electrophoretic mobility shift assays (EMSAs) demonstrated that mesangial cell nuclear fractions contain a multimeric protein complex that bound this region of COX-2 mRNA in a sequence-specific manner. We identified four members of the protein-RNA complex as HuR, TIA-1, TIAR, and the heterogeneous nuclear ribonucleoprotein U (hnRNP U). Treatment of mesangial cells with IL-1beta caused an increase in cytosolic HuR, which was accompanied by an increase in COX-2 mRNA that co-immunoprecipitated with cytosolic HuR. Therefore, we propose that HuR binds to the proximal region of the 3'-UTR of COX-2 following stimulation by IL-1beta and increases the expression of COX-2 mRNA by facilitating its transport out of the nucleus.

3' Untranslated Regions↗

PubMed2001

Distinct regions in the 3' untranslated region are responsible for targeting and stabilizing utrophin transcripts in skeletal muscle cells.

In this study, we have sought to determine whether utrophin transcripts are targeted to a distinct subcellular compartment in skeletal muscle cells, and have examined the role of the 3' untranslated region (UTR) in regulating the stability and localization of utrophin transcripts. Our results show that utrophin transcripts associate preferentially with cytoskeleton-bound polysomes via actin microfilaments. Because this association is not evident in myoblasts, our findings also indicate that the localization of utrophin transcripts with cytoskeleton-bound polysomes is under developmental influences. Transfection of LacZ reporter constructs containing the utrophin 3'UTR showed that this region is critical for targeting chimeric mRNAs to cytoskeleton-bound polysomes and controlling transcript stability. Deletion studies resulted in the identification of distinct regions within the 3'UTR responsible for targeting and stabilizing utrophin mRNAs. Together, these results illustrate the contribution of posttranscriptional events in the regulation of utrophin in skeletal muscle. Accordingly, these findings provide novel targets, in addition to transcriptional events, for which pharmacological interventions may be envisaged to ultimately increase the endogenous levels of utrophin in skeletal muscle fibers from Duchenne muscular dystrophy (DMD) patients.

3' Untranslated Regions↗

PubMed2002

Transcriptional regulation of the MHC class II trans-activator (CIITA) promoter III: identification of a novel regulatory region in the 5'-untranslated region and an important role for cAMP-responsive element binding protein 1 and activating transcription factor-1 in CIITA-promoter III transcriptional activation in B lymphocytes.

The class II trans-activator (CIITA), which acts as a master regulator for expression of MHC class II genes, is expressed constitutively in mature B cells. This constitutive expression of CIITA is driven by CIITA promoter III (CIITA-PIII). However, little is known about the factors that control the B cell-mediated trans-activation of CIITA-PIII. In this study using B cells we have identified several cAMP-responsive elements (CREs) in the proximal promoter and in the 5'-untranslated region (5'-UTR) that are involved in the activation of CIITA-PIII. We show that activating transcription factor (ATF)/CRE binding protein (CREB) factors bind to the CREs in vitro and in vivo. Notably, our results also reveal that the 5'-UTR of CIITA-PIII functions as an important regulatory region in B lymphocytes. Furthermore, transient cotransfections of a CIITA-PIII luciferase reporter construct with either CREB-1 or ATF-1 boost CIITA-PIII trans-activation in a dose-dependent manner, which was further enhanced by addition of general coactivator CREB-binding protein. Transient transfections using mutant CIITA-PIII luciferase reporter constructs that either lack the (5'-UTR) or abolish binding of CREB-1 and ATF-1 to the CRE located in activation response element-2, displayed severely reduced promoter activity in B cells. A similar successive deletion of the CREs resulted in a subsequent reduction of CREB-1-induced activity of CIITA-PIII in B cells. Together our results argue for an important role of ATF/CREB factors and the 5'-UTR of CIITA-PIII in the trans-activation of CIITA-PIII in B cells.

5' Untranslated Regions↗

PubMed2001

Expression of TNF-alpha by herpes simplex virus-infected macrophages is regulated by a dual mechanism: transcriptional regulation by NF-kappa B and activating transcription factor 2/Jun and translational regulation through the AU-rich region of the 3' untranslated region.

Here we have investigated the regulation of TNF-alpha expression in macrophages during HSV-2 infection. Despite a low basal level of TNF-alpha mRNA present in resting macrophages, no TNF-alpha protein is detectable. HSV-2 infection marginally increases the level of TNF-alpha mRNA and protein in resting macrophages, whereas a strong increase is observed in IFN-gamma-activated cells infected with the virus. By reporter gene assay it was found that HSV infection augments TNF-alpha promoter activity. Moreover, treatment of the cells with actinomycin D, which totally blocked mRNA synthesis, only partially prevented accumulation of TNF-alpha protein, indicating that the infection lifts a block on translation of TNF-alpha mRNA. EMSA analysis showed that specific binding to the kappaB#3 site of the murine TNF-alpha promoter was induced within 1 h after infection and persisted beyond 5 h where TNF-alpha expression is down-modulated. Binding to the cAMP responsive element site was also induced but more transiently with kinetics closely following activation of the TNF-alpha promoter. Inhibitors against either NF-kappaB activation or the activating transcription factor 2 kinase p38 abrogated TNF-alpha expression, showing a requirement for both signals for activation of the promoter. This observation was corroborated by reporter gene assays. As to the translational regulation of TNF-alpha, the AU-rich sequence in the 3' untranslated region of the mRNA was found to be responsible for this control because deletion of this region renders mRNA constitutively translationable. These results show that TNF-alpha production is induced by HSV-2 in macrophages through both transcriptional and translational regulation.

3' Untranslated Regions↗

PubMed1983

The sequences of rabbit kappa light chains of b4 and b5 allotypes differ more in their constant regions than in their 3' untranslated regions.

We report the sequence of a cDNA clone encoding the entire variable and constant regions of a rabbit kappa light chain of b5 allotype. The deduced amino acid sequence of the variable region (positions 1-95) is 86% homologous to that of a b4 light chain protein [BS-1) (1) but the b4 and b5 constant regions are only 74% homologous. Comparison of this DNA sequence to that of a cDNA clone encoding a b4 constant region shows that the kappa allotypes b4 and b5 have diverged significantly more in their coding region than in the 3' untranslated regions (86% vs 96% nucleotide sequence homologies). This implies either a function for the 3' untranslated region with evolutionary pressures to conserve or an accelerated divergence of the coding regions.

Amino Acid Sequence↗

PubMed1996

Identification of an RB-responsive region in the 5' untranslated region of the RB gene.

To investigate the ability of the retinoblastoma gene product (RB protein, pRB) to regulate its own expression, cotransfection assays using human RB promoter-luciferase fusion plasmids and a human pRB expression plasmid were employed. In B104, a rat neuroblastoma cell line, pRB stimulated luciferase activity about 2-fold from the wild-type promoter, and about 4-fold from a mutant promoter with a mutation in the retinoblastoma binding factor 1 (RBF-1) site. The RB-responsive region was mapped to a novel 44 bp sequence in the 5' untranslated region in both wild-type and mutant promoters. When apparent stimulation of luciferase activity by pRB was observed, the luciferase mRNA level did not increase, suggesting that through this 44 bp region, pRB could post-transcriptionally regulate its own expression.

Animals↗