The role of nucleotide sugar transporters in development of eukaryotes.
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ABSTRACT:
SUBMITTER: Liu L
PROVIDER: S-EPMC2917499 | biostudies-literature | 2010 Aug
REPOSITORIES: biostudies-literature
Publications
The role of nucleotide sugar transporters in development of eukaryotes.
Liu Li L Xu Yu-Xin YX Hirschberg Carlos B CB
Seminars in cell & developmental biology 20100206 6
The Golgi apparatus membrane of all eukaryotes has nucleotide sugar transporters which play essential roles in the glycosylation of glycoproteins, proteoglycans and glycolipids. Mutations of these transporters have broad developmental phenotypes across many species including diseases in humans and cattle. ...[more]
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Project description:Nucleotide excision repair (NER) is the main pathway used by mammals to remove bulky DNA lesions such as those formed by UV light, environmental mutagens, and some cancer chemotherapeutic adducts from DNA. Deficiencies in NER are associated with the extremely skin cancer-prone inherited disorder xeroderma pigmentosum. Although the core NER reaction and the factors that execute it have been known for some years, recent studies have led to a much more detailed understanding of the NER mechanism, how NER operates in the context of chromatin, and how it is connected to other cellular processes such as DNA damage signaling and transcription. This review emphasizes biochemical, structural, cell biological, and genetic studies since 2005 that have shed light on many aspects of the NER pathway.
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Project description:The transport of carbohydrates by Streptococcus mutans is accomplished by the phosphoenolpyruvate-phosphotrasferase system (PTS) and ATP-binding cassette (ABC) transporters. To undertake a global transcriptional analysis of all S. mutans sugar transporters simultaneously, we used a whole-genome expression microarray. Global transcription profiles of S. mutans UA159 were determined for several carbohydrates. The results revealed that PTSs were responsible for transport of monosaccharides, disaccharides and sugar alcohols. Six PTSs were transcribed only if a specific sugar was present in the growth medium, thus they were regulated at the transcriptional level. These included transporters for fructose, lactose, cellobiose, trehalose, and two transporters for mannitol. Three PTSs were repressed under all conditions tested. Interestingly, five PTSs were always highly expressed regardless of the sugar source used, presumably suggesting their availability for immediate uptake of most common dietary sugars (glucose, fructose, maltose and sucrose). The ABC transporters were found to be specific for polysaccharides, raffinose, stachyose and isomaltosaccharides. Compared to the PTS, the ABC transporters showed higher transcription under several tested conditions, suggesting that they might be transporting multiple substrates. Keywords: carbohydrate response
2007-06-15 | GSE6973 | GEO