Secondary Structure of the Human Membrane-Associated Folate Binding Protein Using a Joint Prediction Approach

Surface proximal convoluted tubules (PCT) in rats were microinfused in situ with [3H]folic acid to study the role of folate binding protein (FBP) in the kidney brush-border membrane for renal conservation and transport of folate [3H]folic acid absorption was linearly related to tubular length of PCT and occurred largely in this segment of the tubule. Unlabeled folate derivatives inhibited [3H]folic acid absorption, the extent of which was dependent on the type of unlabeled folate used and its concentration. At equivalent concentrations, inhibition was most effective with unlabeled folic acid, slightly lower than with 5-methyltetrahydrofolate and least effective with methotrexate. Comparisons between [3H]folic acid absorption before and after infusion of a saturating dose of unlabeled folic acid or repetitive injections of [3H]folic acid into the same tubular site revealed continuous and rapid regeneration of unsaturated folic acid uptake sites with an apparent half-life of 28.75 +/- 8.75 s. Determination of [3H] retained in the tubule at various periods after microinfusion of [3H]folic acid revealed slow cellular disappearance with an apparent half-life of 47.3 +/- 5.4 min. It is proposed that the brush-border FBP functions as a receptor of infused folic acid and that following the binding of the ligand the folic acid/FBP complex undergoes a rapid change that results in the internalization of folic acid and regeneration of unsaturated binding sites at the membrane surface. Internalized folic acid is slowly released into renal capillaries.

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Involvement of the Escherichia coli folate-binding protein YgfZ in RNA modification and regulation of chromosomal replication initiation

Molecular Microbiology ◽

10.1111/j.1365-2958.2005.04932.x ◽

2006 ◽

Vol 59 (1) ◽

pp. 265-275 ◽

Cited By ~ 23

Author(s):

Tomotake Ote ◽

Masayuki Hashimoto ◽

Yoshiho Ikeuchi ◽

Masayuki Su'etsugu ◽

Tsutomu Suzuki ◽

...

Keyword(s):

Escherichia Coli ◽

Binding Protein ◽

Replication Initiation ◽

Rna Modification ◽

Chromosomal Replication ◽

Folate Binding Protein

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miR-Explore: Predicting MicroRNA Precursors by Class Grouping and Secondary Structure Positional Alignment

Bioinformatics and Biology Insights ◽

10.4137/bbi.s10758 ◽

2013 ◽

Vol 7 ◽

pp. BBI.S10758 ◽

Cited By ~ 1

Author(s):

Bram Sebastian ◽

Samuel E. Aggrey

Keyword(s):

Secondary Structure ◽

Comparative Method ◽

High Specificity ◽

Computational Prediction ◽

Training Data ◽

Structure Alignment ◽

Global Alignment ◽

Gene Expressions ◽

Small Noncoding Rnas ◽

Prediction Approach

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expressions by targeting the mRNAs especially in the 3′UTR regions. The identification of miRNAs has been done by biological experiment and computational prediction. The computational prediction approach has been done using two major methods: comparative and noncomparative. The comparative method is dependent on the conservation of the miRNA sequences and secondary structure. The noncomparative method, on the other hand, does not rely on conservation. We hypothesized that each miRNA class has its own unique set of features; therefore, grouping miRNA by classes before using them as training data will improve sensitivity and specificity. The average sensitivity was 88.62% for miR-Explore, which relies on within miRNA class alignment, and 70.82% for miR-abela, which relies on global alignment. Compared with global alignment, grouping miRNA by classes yields a better sensitivity with very high specificity for pre-miRNA prediction even when a simple positional based secondary and primary structure alignment are used.

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