| Research Abstract |
We isolated the fetal brain-enriched cDNA clones whose corresponding mRNAs were expressed preferentially in the fetal brain during the brain development, and analyzed the mRNA expression in the human brain tumors. Using the differential screening and cDNA subtraction procedures, we identified 22 distinct fetal brain-enriched cDNA clones which included beta-tubulin Mbeta5, beta-tubulin Mbeta2, alpha-tubulin Malpha1, thymosin beta10, stathmin, neuronatin, ferritin L chain, alpha-internexin, amphoterin, PI-kinase type IIbeta, SAPAP-4, MARKS,MAZ,and MN1. We also isolated the full length cDNA of 3 novel clones (FBE5, FBE88, FBE254) and analyzed their coding proteins. The clone FBE88 revealed to encode a novel transcriptional regulatory protein which belonged to Polycomb-group (PcG) genes and showed some similarity to a Drosophila tumor suppressor gene, lethal (3) malignant brain tumor. Among the results of the expression analyzes of the mRNAs corresponding to the isolated fetal brain-enriched clones in various human tumors, the expression pattern of the neuronatin mRNA seemed noteworthy. The neuronatin mRNA was expressed selectively in human pituitary adenomas among various human tumor tissues and abundantly in almost all non-functioning adenomas which express no functional hormones, suggesting the possible utility of the neuronatin as a new tumor marker of the human pituitary adenomas.
|
