Abstract
SLC26A6 (putative anion transporter 1, PAT1) has been shown to play an important role in mediating the luminal Cl-/OH-(HCO 3-) exchange process in the intestine. Very little is known about the molecular mechanisms involved in the transcriptional regulation of intestinal SLC26A6 gene expression in the intestine. Current studies were, therefore, designed to clone and characterize the 5′-regulatory region of the human SLC26A6 gene and determine the mechanisms involved in its regulation. A 1,120 bp (p-964/+156) SLC26A6 promoter fragment cloned upstream to the luciferase reporter gene in pGL2-basic exhibited high promoter activity when transfected in Caco2 cells. Progressive deletions of the 5′-flanking region demonstrated that -214/-44 region of the promoter harbors cis-acting elements important for maximal SLC26A6 promoter activity. Since, diarrhea associated with inflammatory bowel diseases is attributed to increased secretion of pro-inflammatory cytokines, we examined the effects of IFNγ (30 ng/ml, 24 h) on SLC26A6 function, expression and promoter activity. IFNγ decreased both SLC26A6 mRNA and function and repressed SLC26A6 promoter activity. Deletion analysis indicated that IFNγ response element is located between -414/-214 region and sequence analysis of this region revealed the presence of potential Interferon Stimulated Responsive Element (ISRE), a binding site (-318/-300 bp) for interferon regulatory factor-1 transcription factor (IRF-1). Mutations in the potential ISRE site abrogated the inhibitory effects of IFNγ. These studies provided novel evidence for the involvement of IRF-1 in the regulation of SLC26A6 gene expression by IFNg in the human intestine.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 454-466 |
| Number of pages | 13 |
| Journal | Journal of Cellular Biochemistry |
| Volume | 105 |
| Issue number | 2 |
| DOIs | |
| State | Published - Oct 1 2008 |
Fingerprint
Keywords
- Human intestine and chloride absorption
- IFNγ
- IRF-1
- Putative Anion Transporter 1 (PAT1) promoter
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology
Cite this
Characterization of the 5′-flanking region and regulation of expression of human anion exchanger SLC26A6. / Saksena, Seema; Dwivedi, Alka; Singla, Amika; Gill, Ravinder K.; Tyagi, Sangeeta; Borthakur, Alip; Alrefai, Waddah A.; Ramaswamy, Krishnamurthy; Dudeja, Pradeep K.
In: Journal of Cellular Biochemistry, Vol. 105, No. 2, 01.10.2008, p. 454-466.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Characterization of the 5′-flanking region and regulation of expression of human anion exchanger SLC26A6
AU - Saksena, Seema
AU - Dwivedi, Alka
AU - Singla, Amika
AU - Gill, Ravinder K.
AU - Tyagi, Sangeeta
AU - Borthakur, Alip
AU - Alrefai, Waddah A.
AU - Ramaswamy, Krishnamurthy
AU - Dudeja, Pradeep K.
PY - 2008/10/1
Y1 - 2008/10/1
N2 - SLC26A6 (putative anion transporter 1, PAT1) has been shown to play an important role in mediating the luminal Cl-/OH-(HCO 3-) exchange process in the intestine. Very little is known about the molecular mechanisms involved in the transcriptional regulation of intestinal SLC26A6 gene expression in the intestine. Current studies were, therefore, designed to clone and characterize the 5′-regulatory region of the human SLC26A6 gene and determine the mechanisms involved in its regulation. A 1,120 bp (p-964/+156) SLC26A6 promoter fragment cloned upstream to the luciferase reporter gene in pGL2-basic exhibited high promoter activity when transfected in Caco2 cells. Progressive deletions of the 5′-flanking region demonstrated that -214/-44 region of the promoter harbors cis-acting elements important for maximal SLC26A6 promoter activity. Since, diarrhea associated with inflammatory bowel diseases is attributed to increased secretion of pro-inflammatory cytokines, we examined the effects of IFNγ (30 ng/ml, 24 h) on SLC26A6 function, expression and promoter activity. IFNγ decreased both SLC26A6 mRNA and function and repressed SLC26A6 promoter activity. Deletion analysis indicated that IFNγ response element is located between -414/-214 region and sequence analysis of this region revealed the presence of potential Interferon Stimulated Responsive Element (ISRE), a binding site (-318/-300 bp) for interferon regulatory factor-1 transcription factor (IRF-1). Mutations in the potential ISRE site abrogated the inhibitory effects of IFNγ. These studies provided novel evidence for the involvement of IRF-1 in the regulation of SLC26A6 gene expression by IFNg in the human intestine.
AB - SLC26A6 (putative anion transporter 1, PAT1) has been shown to play an important role in mediating the luminal Cl-/OH-(HCO 3-) exchange process in the intestine. Very little is known about the molecular mechanisms involved in the transcriptional regulation of intestinal SLC26A6 gene expression in the intestine. Current studies were, therefore, designed to clone and characterize the 5′-regulatory region of the human SLC26A6 gene and determine the mechanisms involved in its regulation. A 1,120 bp (p-964/+156) SLC26A6 promoter fragment cloned upstream to the luciferase reporter gene in pGL2-basic exhibited high promoter activity when transfected in Caco2 cells. Progressive deletions of the 5′-flanking region demonstrated that -214/-44 region of the promoter harbors cis-acting elements important for maximal SLC26A6 promoter activity. Since, diarrhea associated with inflammatory bowel diseases is attributed to increased secretion of pro-inflammatory cytokines, we examined the effects of IFNγ (30 ng/ml, 24 h) on SLC26A6 function, expression and promoter activity. IFNγ decreased both SLC26A6 mRNA and function and repressed SLC26A6 promoter activity. Deletion analysis indicated that IFNγ response element is located between -414/-214 region and sequence analysis of this region revealed the presence of potential Interferon Stimulated Responsive Element (ISRE), a binding site (-318/-300 bp) for interferon regulatory factor-1 transcription factor (IRF-1). Mutations in the potential ISRE site abrogated the inhibitory effects of IFNγ. These studies provided novel evidence for the involvement of IRF-1 in the regulation of SLC26A6 gene expression by IFNg in the human intestine.
KW - Human intestine and chloride absorption
KW - IFNγ
KW - IRF-1
KW - Putative Anion Transporter 1 (PAT1) promoter
UR - http://www.scopus.com/inward/record.url?scp=54849421781&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=54849421781&partnerID=8YFLogxK
U2 - 10.1002/jcb.21842
DO - 10.1002/jcb.21842
M3 - Article
C2 - 18655181
AN - SCOPUS:54849421781
VL - 105
SP - 454
EP - 466
JO - Journal of Cellular Biochemistry
JF - Journal of Cellular Biochemistry
SN - 0730-2312
IS - 2
ER -