Cloning of alkaline sphingomyelinase from rat intestinal mucosa and adjusting of the hypothetical protein XP_221184 in GenBank.
(2005) In Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids 1687(1-3). p.94-102- Abstract
- Intestinal alkaline sphingomyelinase (alk-SMase) digests sphingomyelin and the process may influence colonic tumorigenesis and cholesterol absorption. We recently identified the gene of human alk-SMase and cloned the cDNA. Cross-species screening of homology in GenBank found a hypothetical rat protein, XP_221184, with 491 amino acid residues, which shares 73% identity with human alk-SMase. Based on the cDNA sequence of this protein, we cloned a cDNA from rat intestinal mucosa by RT-PCR. The cloned cDNA encodes a protein with 439 amino acid residues and higher (85%) identity with human alk-SMase. The cloned cDNA differed from the XP_221184 cDNA in splice sites linking exons 2 and 3, and exons 3 and 4, respectively. In the sequence of the... (More)
- Intestinal alkaline sphingomyelinase (alk-SMase) digests sphingomyelin and the process may influence colonic tumorigenesis and cholesterol absorption. We recently identified the gene of human alk-SMase and cloned the cDNA. Cross-species screening of homology in GenBank found a hypothetical rat protein, XP_221184, with 491 amino acid residues, which shares 73% identity with human alk-SMase. Based on the cDNA sequence of this protein, we cloned a cDNA from rat intestinal mucosa by RT-PCR. The cloned cDNA encodes a protein with 439 amino acid residues and higher (85%) identity with human alk-SMase. The cloned cDNA differed from the XP_221184 cDNA in splice sites linking exons 2 and 3, and exons 3 and 4, respectively. In the sequence of the cloned protein, the predicted activity motif, sphingomyelin binding sites, and potential glycosylation sites in human alk-SMase are all conserved. To confirm the cloned protein is the real form of alk-SMase, native alk-SMase was purified from rat intestine and subjected to proteolytic digestion followed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry and electrospray ionization (ESI) tandem mass spectrometry. Seven tryptic peptides were found to match the cloned protein sequence. Transient expression of the cloned cDNA linked with a myc tag in COS-7 cells demonstrated high SMase activity, with an optimal pH at 9.0 and a specific dependence on taurocholate and taurochenodeoxycholate. The expressed protein reacted with both anti-myc and anti-human alk-SMase antibodies. Northern blotting of rat tissues revealed high levels of mRNA in jejunum but not in other tissues. In conclusion, we cloned rat alk-SMase cDNA from rat intestine, adjusted the putative rat alk-SMase protein in GenBank, and confirmed the specific expression of the gene in the small intestine. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/133772
- author
- Wu, Jun LU ; Cheng, Yajun LU ; Palmberg, Carina ; Bergman, Tomas ; Nilsson, Åke LU and Duan, Rui-Dong LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- cloning, XP_221184, alkaline sphingomyelinase
- in
- Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids
- volume
- 1687
- issue
- 1-3
- pages
- 94 - 102
- publisher
- Elsevier
- external identifiers
-
- pmid:15708357
- wos:000227247200010
- scopus:13644266356
- ISSN
- 1388-1981
- DOI
- 10.1016/j.bbalip.2004.11.006
- language
- English
- LU publication?
- yes
- id
- 9f8bf731-1849-4799-8181-4f4162efbff8 (old id 133772)
- date added to LUP
- 2016-04-01 16:46:06
- date last changed
- 2024-01-11 14:24:37
@article{9f8bf731-1849-4799-8181-4f4162efbff8, abstract = {{Intestinal alkaline sphingomyelinase (alk-SMase) digests sphingomyelin and the process may influence colonic tumorigenesis and cholesterol absorption. We recently identified the gene of human alk-SMase and cloned the cDNA. Cross-species screening of homology in GenBank found a hypothetical rat protein, XP_221184, with 491 amino acid residues, which shares 73% identity with human alk-SMase. Based on the cDNA sequence of this protein, we cloned a cDNA from rat intestinal mucosa by RT-PCR. The cloned cDNA encodes a protein with 439 amino acid residues and higher (85%) identity with human alk-SMase. The cloned cDNA differed from the XP_221184 cDNA in splice sites linking exons 2 and 3, and exons 3 and 4, respectively. In the sequence of the cloned protein, the predicted activity motif, sphingomyelin binding sites, and potential glycosylation sites in human alk-SMase are all conserved. To confirm the cloned protein is the real form of alk-SMase, native alk-SMase was purified from rat intestine and subjected to proteolytic digestion followed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry and electrospray ionization (ESI) tandem mass spectrometry. Seven tryptic peptides were found to match the cloned protein sequence. Transient expression of the cloned cDNA linked with a myc tag in COS-7 cells demonstrated high SMase activity, with an optimal pH at 9.0 and a specific dependence on taurocholate and taurochenodeoxycholate. The expressed protein reacted with both anti-myc and anti-human alk-SMase antibodies. Northern blotting of rat tissues revealed high levels of mRNA in jejunum but not in other tissues. In conclusion, we cloned rat alk-SMase cDNA from rat intestine, adjusted the putative rat alk-SMase protein in GenBank, and confirmed the specific expression of the gene in the small intestine.}}, author = {{Wu, Jun and Cheng, Yajun and Palmberg, Carina and Bergman, Tomas and Nilsson, Åke and Duan, Rui-Dong}}, issn = {{1388-1981}}, keywords = {{cloning; XP_221184; alkaline sphingomyelinase}}, language = {{eng}}, number = {{1-3}}, pages = {{94--102}}, publisher = {{Elsevier}}, series = {{Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids}}, title = {{Cloning of alkaline sphingomyelinase from rat intestinal mucosa and adjusting of the hypothetical protein XP_221184 in GenBank.}}, url = {{https://lup.lub.lu.se/search/files/4774631/624392.pdf}}, doi = {{10.1016/j.bbalip.2004.11.006}}, volume = {{1687}}, year = {{2005}}, }