Amplified DNA in Y1 mouse adrenal tumor cells: isolation of cDNAs complementary to an amplified c-Ki-ras gene and localization of homologous sequences to mouse chromosome 6.

We have isolated cDNA clones complementary to a c-Ki-ras cellular oncogene that is amplified in Y1 mouse adrenal tumor cells, with the amplified sequences located on double-minute chromatin bodies (DMs) and homogeneously staining chromosomal regions (HSRs). Characterization of the cDNAs included the isolation of corresponding genomic clones, Northern blot analysis of RNA, and DNA sequence analysis. Our studies demonstrate that the c-Ki-ras gene amplified in the Y1 cells is homologous to the human c-Ki-ras2 gene. We have also obtained evidence that, in addition to c-Ki-ras, at least one other transcription unit has been amplified in the mouse adrenal tumor cells. Moreover, by Southern blot analysis of Chinese hamster-mouse somatic cell hybrids, we have determined that the amplified DNA sequences associated with DMs and HSRs, including the c-Ki-ras gene, are present in normal mouse cells on chromosome 6

The human fatty acid transport protein-1 (SLC27A1; FATP-1) cDNA and gene: organization, chromosomal localization, and expression

Uptake of fatty acids into cells is a controlled process in part regulated by fatty acid transport proteins (FATPs), which facilitate the transport of fatty acids across the cell membrane. In this study the structure of the human FATP-1 (HGMW-approved symbol SLC27A1) cDNA and gene was determined, and the expression of its mRNA in human was characterized. Muscle and adipose tissue have the highest levels of FATP-1 mRNA, small intestine has intermediate levels, and FATP-1 mRNA is barely detectable in liver. The human FATP-1 gene has 12 exons and extends over more than 13 kb of genomic DNA. The FATP gene maps to chromosome 19p13.1 by fluorescence in situ hybridization, a region previously suggested to be implicated in the determination of small dense low-density lipoprotein (LDL). Knowledge of the gene structure and chromosomal localization will allow screening for FATP mutations in humans with metabolic disorders, whereas knowledge of its expression pattern and factors regulating its expression could be of importance in understanding its biology