title: Riboflavin transporter-2 (rft-2) of Caenorhabditis elegans: Adaptive and developmental regulation.
abstract: Riboflavin transporters (rft-1 and rft-2), orthologous to human riboflavin transporter-3 (hRVFT-3), are identified and characterized in Caenorhabditis elegans. However, studies pertaining to functional contribution of rft-2 in maintaining body homeostatic riboflavin levels and its regulation are very limited. In this study, the expression pattern of rft-2 at different life stages of C. elegans was studied through real-time PCR, and found to be consistent from larval to adult stages that demonstrate its involvement in maintaining the body homeostatic riboflavin levels at whole animal level all through its life. A possible regulation of rft-2 expression at mRNA levels at whole animal was studied after adaptation to low and high concentrations of riboflavin. Abundance of rft-2 transcript was upregulated in riboflavin-deficient conditions (10 nM), while it was downregulated with riboflavin-supplemented conditions (2 mM) as compared with control (10 meu M). Further, the 5'-regulatory region of the rft-2 gene was cloned, and transgenic nematodes expressing transcriptional rft-2 promoter::GFP fusion constructs were generated. The expression of rft-2 was found to be adaptively regulated in vivo when transgenic worms were maintained under different extracellular riboflavin levels, which was also mediated partly via changes in the rft-2 levels that directs towards the possible involvement of transcriptional regulatory events.
authors.affiliation: Department of Genetic Engineering, School of Biotechnology, Madurai Kamaraj University, Madurai 625 021, India.
authors.forename: Krishnan
authors.initials: K
authors.lastname: Gandhimathi
authors.forename: Sellamuthu
authors.initials: S
authors.lastname: Karthi
authors.forename: Paramasivam
authors.initials: P
authors.lastname: Manimaran
authors.forename: Perumal
authors.initials: P
authors.lastname: Varalakshmi
authors.forename: Balasubramaniem
authors.initials: B
authors.lastname: Ashokkumar
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001692:Biological Transport / Q000235:genetics; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000096:biosynthesis / Q000235:genetics*; D005786:Gene Expression Regulation / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics; D007814:Larva / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis; D034741:RNA, Small Interfering; D060888:Real-Time Polymerase Chain Reaction; D012256:Riboflavin / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D029742:Caenorhabditis elegans Proteins; D026901:Membrane Transport Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C583179:Rft-2 protein, C elegans; D049452:Green Fluorescent Proteins; D012256:Riboflavin