Abstract
A rat kidney- and intestine-specific cDNA (D2) that induces high-affinity, Na+-independent uptake of cystine and dibasic and neutral amino acids into cRNA-injected Xenopus oocytes was recently isolated by expression cloning in our laboratory (R. G. Wells and M. A. Hediger. Proc. Natl. Acad. Sci. USA 89: 5596-5600, 1992). At present it is not known whether the D2-encoded protein functions as a transporter or as a transporter activator. To gain more insight into the role of D2 in renal amino acid transport, we studied the site of its expression in the kidney. This was determined by Northern blot analysis and by using a combination of in situ hybridization and immunocytochemistry with antibodies that recognize specific proximal tubule segments. D2 antisense RNA hybridized to the same tubular segments that were strongly positive for anti-ecto-adenosinetriphosphatase but negative for carbonic anhydrase type IV and the facilitated glucose transporter GLUT2. We conclude that D2 mRNA is strongly expressed in the rat kidney proximal tubule S3 segment, although there is weak hybridization to the S1 and S2 segments. The signal is absent in all other parts of the kidney. The S3 specific expression of D2 mRNA coincides with the site of high-affinity transport of cystine and other amino acids, consistent with the proposed involvement of D2 in these processes.
| Original language | English |
|---|---|
| Journal | American Journal of Physiology - Renal Fluid and Electrolyte Physiology |
| Volume | 263 |
| Issue number | 6 32-6 |
| Publication status | Published - Dec 1992 |
| Externally published | Yes |
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Keywords
- Carbonic anhydrase
- Cystine transport
- Cystinuria
- Ecto-adenosinetriphosphatase
- GLUT2
- Immunocytochemistry
- In situ hybridization
- Kidney
ASJC Scopus subject areas
- Physiology
Cite this
Expression of mRNA (D2) encoding a protein involved in amino acid transport in S3 proximal tubule. / Kanai, Yoshikatsu; Stelzner, Matthias G.; Lee, Wen Sen; Wells, Rebecca G.; Brown, Dennis; Hediger, Matthias A.
In: American Journal of Physiology - Renal Fluid and Electrolyte Physiology, Vol. 263, No. 6 32-6, 12.1992.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Expression of mRNA (D2) encoding a protein involved in amino acid transport in S3 proximal tubule
AU - Kanai, Yoshikatsu
AU - Stelzner, Matthias G.
AU - Lee, Wen Sen
AU - Wells, Rebecca G.
AU - Brown, Dennis
AU - Hediger, Matthias A.
PY - 1992/12
Y1 - 1992/12
N2 - A rat kidney- and intestine-specific cDNA (D2) that induces high-affinity, Na+-independent uptake of cystine and dibasic and neutral amino acids into cRNA-injected Xenopus oocytes was recently isolated by expression cloning in our laboratory (R. G. Wells and M. A. Hediger. Proc. Natl. Acad. Sci. USA 89: 5596-5600, 1992). At present it is not known whether the D2-encoded protein functions as a transporter or as a transporter activator. To gain more insight into the role of D2 in renal amino acid transport, we studied the site of its expression in the kidney. This was determined by Northern blot analysis and by using a combination of in situ hybridization and immunocytochemistry with antibodies that recognize specific proximal tubule segments. D2 antisense RNA hybridized to the same tubular segments that were strongly positive for anti-ecto-adenosinetriphosphatase but negative for carbonic anhydrase type IV and the facilitated glucose transporter GLUT2. We conclude that D2 mRNA is strongly expressed in the rat kidney proximal tubule S3 segment, although there is weak hybridization to the S1 and S2 segments. The signal is absent in all other parts of the kidney. The S3 specific expression of D2 mRNA coincides with the site of high-affinity transport of cystine and other amino acids, consistent with the proposed involvement of D2 in these processes.
AB - A rat kidney- and intestine-specific cDNA (D2) that induces high-affinity, Na+-independent uptake of cystine and dibasic and neutral amino acids into cRNA-injected Xenopus oocytes was recently isolated by expression cloning in our laboratory (R. G. Wells and M. A. Hediger. Proc. Natl. Acad. Sci. USA 89: 5596-5600, 1992). At present it is not known whether the D2-encoded protein functions as a transporter or as a transporter activator. To gain more insight into the role of D2 in renal amino acid transport, we studied the site of its expression in the kidney. This was determined by Northern blot analysis and by using a combination of in situ hybridization and immunocytochemistry with antibodies that recognize specific proximal tubule segments. D2 antisense RNA hybridized to the same tubular segments that were strongly positive for anti-ecto-adenosinetriphosphatase but negative for carbonic anhydrase type IV and the facilitated glucose transporter GLUT2. We conclude that D2 mRNA is strongly expressed in the rat kidney proximal tubule S3 segment, although there is weak hybridization to the S1 and S2 segments. The signal is absent in all other parts of the kidney. The S3 specific expression of D2 mRNA coincides with the site of high-affinity transport of cystine and other amino acids, consistent with the proposed involvement of D2 in these processes.
KW - Carbonic anhydrase
KW - Cystine transport
KW - Cystinuria
KW - Ecto-adenosinetriphosphatase
KW - GLUT2
KW - Immunocytochemistry
KW - In situ hybridization
KW - Kidney
UR - http://www.scopus.com/inward/record.url?scp=0027054424&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0027054424&partnerID=8YFLogxK
M3 - Article
VL - 263
JO - American Journal of Physiology - Renal Physiology
JF - American Journal of Physiology - Renal Physiology
SN - 1931-857X
IS - 6 32-6
ER -