Cloning and characterization of 5'-upstream sequence of the M32 gene for a mouse homologue of Drosophila heterochromatin protein 1 (HP1).
M32 [also termed chromatin modifier protein 2 (MOD2)] is a nuclear protein consisting of the condensed chromatin structure (heterochromatin) and considered one of the mammalian homologues of heterochromatin protein 1 (HP1), first isolated as one of the components of heterochromatin in Drosophila. This report presents the isolation and characterization of the 5'-upstream region of the mouse M32 gene containing a promoter region and 5'-untranslated region (5'-UTR) exon. The 5'-upstream region (approximately 0.27 kb starting from the 5' end of the 5'-UTR exon) of the M32 gene contained neither a TATA box nor a CCAAT box, but possessed potential binding sites for transcription factors such as Sp1, H4TF-1, PEA2, PEA3, GSG element and Egr-1, and was highly G/C-rich. The promoter activity of this 5'-upstream region was demonstrated by transfecting its fusion-construct with the E. coli beta-galactosidase gene into the F9 mouse teratocarcinoma cell line. The 5' ends of the mRNA were mapped to at least two positions in the 5'-upstream region. Interestingly, the 5'-upstream region exhibited a high degree of similarity to a portion of heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 gene, which is thought to play a role in RNA processing, located in the reverse orientation to the M32 gene, and also to several known ESTs and cDNAs. These findings suggest that the 5'-upstream region of the M32 gene consists of a multiple regulatory complex which probably plays important roles in nuclear function such as chromatin organization and RNA processing.
Sato
M
M
Molecular Medicine Research Center, Institute of Medical Sciences, School of Medicine, Tokai University, Bohseidai, Isehara, Kanagawa 259-1193, Japan. masasato@is.icc.u-tokai.ac.jp
Miyado
K
K
Kimura
M
M
D024506:5' Flanking Region / Q000235:genetics*; D000818:Animals; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics*; D003001:Cloning, Molecular; D029721:Drosophila Proteins; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D024363:Transcription Initiation Site
D002868:Chromosomal Proteins, Non-Histone; D029721:Drosophila Proteins; C452193:heterochromatin protein 1, Drosophila