Abstract
Transcription from the ASNS (asparagine synthetase) gene is increased in response to either amino acid (amino acid response) or glucose (endoplasmic reticulum stress response) deprivation. These two independent pathways converge on the same set of genomic cis-elements within the ASNS promoter, referred to as nutrient-sensing response element-1 and -2. Chromatin immunoprecipitation analysis provides the first in vivo evidence for activating transcription factor (ATF)-3 binding to the proximal ASNS promoter containing the nutrient-sensing response element-1 sequence. Overexpression of the full-length ATF3 protein caused a concentration-dependent biphasic response in ASNS promoter-driven transcription. Both amino acid limitation and activation of the endoplasmic reticulum stress response by glucose deprivation caused an increase in ATF3 mRNA content. However, reverse transcriptase-PCR analysis revealed that the increase in the ATF3 mRNA species detected by Northern analysis actually encoded both full-length ATF3 and two predicted truncated ATF3 isoforms (ATF3ΔZip2c and ATF3ΔZip3). Based on sequence analysis, one of the predicted truncated proteins (ATF3ΔZip3) is likely incapable of binding DNA; and yet, exogenous expression of the cDNA enhanced starvation-induced or ATF4-activated ASNS transcription, possibly by sequestering corepressor proteins. Collectively, the results provide evidence for a potential role of multiple predicted ATF3 isoforms in the transcriptional regulation of the ASNS gene in response to nutrient deprivation.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 38402-38412 |
| Number of pages | 11 |
| Journal | Journal of Biological Chemistry |
| Volume | 278 |
| Issue number | 40 |
| DOIs | |
| State | Published - Oct 3 2003 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology
Cite this
Amino acid deprivation and endoplasmic reticulum stress induce expression of multiple activating transcription factor-3 mRNA species that, when overexpressed in HepG2 cells, modulate transcription by the human asparagine synthetase promoter. / Pan, Yuan Xiang; Chen, Hong; Siu, Fai; Kilberg, Michael S.
In: Journal of Biological Chemistry, Vol. 278, No. 40, 03.10.2003, p. 38402-38412.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Amino acid deprivation and endoplasmic reticulum stress induce expression of multiple activating transcription factor-3 mRNA species that, when overexpressed in HepG2 cells, modulate transcription by the human asparagine synthetase promoter
AU - Pan, Yuan Xiang
AU - Chen, Hong
AU - Siu, Fai
AU - Kilberg, Michael S.
PY - 2003/10/3
Y1 - 2003/10/3
N2 - Transcription from the ASNS (asparagine synthetase) gene is increased in response to either amino acid (amino acid response) or glucose (endoplasmic reticulum stress response) deprivation. These two independent pathways converge on the same set of genomic cis-elements within the ASNS promoter, referred to as nutrient-sensing response element-1 and -2. Chromatin immunoprecipitation analysis provides the first in vivo evidence for activating transcription factor (ATF)-3 binding to the proximal ASNS promoter containing the nutrient-sensing response element-1 sequence. Overexpression of the full-length ATF3 protein caused a concentration-dependent biphasic response in ASNS promoter-driven transcription. Both amino acid limitation and activation of the endoplasmic reticulum stress response by glucose deprivation caused an increase in ATF3 mRNA content. However, reverse transcriptase-PCR analysis revealed that the increase in the ATF3 mRNA species detected by Northern analysis actually encoded both full-length ATF3 and two predicted truncated ATF3 isoforms (ATF3ΔZip2c and ATF3ΔZip3). Based on sequence analysis, one of the predicted truncated proteins (ATF3ΔZip3) is likely incapable of binding DNA; and yet, exogenous expression of the cDNA enhanced starvation-induced or ATF4-activated ASNS transcription, possibly by sequestering corepressor proteins. Collectively, the results provide evidence for a potential role of multiple predicted ATF3 isoforms in the transcriptional regulation of the ASNS gene in response to nutrient deprivation.
AB - Transcription from the ASNS (asparagine synthetase) gene is increased in response to either amino acid (amino acid response) or glucose (endoplasmic reticulum stress response) deprivation. These two independent pathways converge on the same set of genomic cis-elements within the ASNS promoter, referred to as nutrient-sensing response element-1 and -2. Chromatin immunoprecipitation analysis provides the first in vivo evidence for activating transcription factor (ATF)-3 binding to the proximal ASNS promoter containing the nutrient-sensing response element-1 sequence. Overexpression of the full-length ATF3 protein caused a concentration-dependent biphasic response in ASNS promoter-driven transcription. Both amino acid limitation and activation of the endoplasmic reticulum stress response by glucose deprivation caused an increase in ATF3 mRNA content. However, reverse transcriptase-PCR analysis revealed that the increase in the ATF3 mRNA species detected by Northern analysis actually encoded both full-length ATF3 and two predicted truncated ATF3 isoforms (ATF3ΔZip2c and ATF3ΔZip3). Based on sequence analysis, one of the predicted truncated proteins (ATF3ΔZip3) is likely incapable of binding DNA; and yet, exogenous expression of the cDNA enhanced starvation-induced or ATF4-activated ASNS transcription, possibly by sequestering corepressor proteins. Collectively, the results provide evidence for a potential role of multiple predicted ATF3 isoforms in the transcriptional regulation of the ASNS gene in response to nutrient deprivation.
UR - http://www.scopus.com/inward/record.url?scp=0141866865&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0141866865&partnerID=8YFLogxK
U2 - 10.1074/jbc.M304574200
DO - 10.1074/jbc.M304574200
M3 - Article
C2 - 12881527
AN - SCOPUS:0141866865
VL - 278
SP - 38402
EP - 38412
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 40
ER -