1. Preferential transcription of a gene for alpha amylase in the carcinoid tumor of African rodent Mastomys natalensis.
- Author
-
Daa T, Sato T, Kashima K, Nakayama I, Yokoyama S, Takeno S, Noguchi T, and Uchida Y
- Subjects
- Africa, Animals, Base Sequence, Blotting, Northern, Carcinoid Tumor pathology, Cloning, Molecular, DNA, Neoplasm metabolism, Gene Expression Profiling, Gene Library, Immunoenzyme Techniques, Molecular Sequence Data, Muridae genetics, RNA, Messenger metabolism, RNA, Neoplasm metabolism, Rodentia, Sequence Homology, Nucleic Acid, alpha-Amylases isolation & purification, Carcinoid Tumor enzymology, Muridae metabolism, alpha-Amylases genetics
- Abstract
The carcinoid tumor in Mastomys natalensis provides a useful animal model of tumorigenesis. We investigated preferentially transcribed genes in this carcinoid tumor by differential hybridization. Fourteen clones corresponding to high levels of transcription were isolated from a cDNA library. Sequencing analysis and a homology search revealed that the clones corresponded to genes for chromogranin and alpha-amylase. High-level transcription of a gene for alpha-amylase gene in Mastomys carcinoid tumor was confirmed by Northern blotting analysis. Furthermore, Western blotting analysis confirmed the expression of alpha-amylase in tumors at the protein level. Immunohistochemical staining revealed alpha-amylase in the cytoplasm of Mastomys carcinoid tumors. Our results demonstrated that an exocrine enzyme 'amylase' could be produced ectopically by a neuroen docrine tumor.
- Published
- 2002