ABSTRACT
We describe the cloning of a near full-length cDNA of 4258 nucleotides encoding freac-9 (HGMW-approved symbol FKHL17), a novel human forkhead gene. The 5' untranslated region is unusual since it is very long, 2127 nucleotides, and contains 15 upstream AUG codons. Hybridization to a panel consisting of RNA derived from 50 different tissues showed that freac-9 is transcribed exclusively in the kidney. The kidney-derived cell lines COS-7 and 293 are shown to express freac-9. A combination of fluorescence in situ hybridization and somatic cell hybrids localizes freac-9 to the chromosomal region of 1p32-p34. The conceptual translation product predicts a protein of 372 amino acids with an N-terminal domain rich in acidic amino acids and with a high likelihood of forming an amphipatic helix, a DNA binding forkhead domain, and a C-terminal region that has a high probability of forming an amphipatic beta-sheet. The amino acid sequence of the DNA binding forkhead motif of FREAC-9 is identical to that of another forkhead protein, FREAC-4, whereas 12 substitutions are present at the nucleotide level. There are no similarities in regions outside of the DNA binding domains of FREAC-9 and FREAC-4 and since freac-4 maps to a different chromosome (5q12-q13) it is likely that an evolutionary selection has acted to maintain identical DNA binding domains between these two kidney expressed transcription factors.
Subject(s)
Chromosome Mapping , Chromosomes, Human, Pair 1/genetics , Kidney/chemistry , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Genes/genetics , Humans , Molecular Sequence Data , Organ Specificity , RNA, Messenger/analysis , Sequence Analysis, DNA , Sequence Homology, Amino AcidABSTRACT
An experimental animal model using a closed system to study the sensitivity of radiopharmaceuticals for the detection and localization of gastrointestinal (GI) bleeding site in a sheep was developed. This model was validated with 99mTc-DTPA. Radioactivity as low as 85.47 +/- 13.32 kBq in a volume of 2.1 +/- 0.14 ml at a bleeding rate of 0.07 ml/min was detected. Simulated intermittent bleeding experiments indicated that at 1 h after injection of 99mTc-DTPA there was still enough circulating radioactivity to bleed into the gut and that it was possible to perform repeat injection of 99mTc-DTPA as early as 2 h after the first injection.
