A. Scorilas et al., Genomic organization, physical mapping, and expression analysis of the human protein arginine methyltransferase 1 gene, BIOC BIOP R, 278(2), 2000, pp. 349-359
Citations number
37
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Protein arginine methyltransferases (PRMTs) regulate mRNA processing and ma
turation by modulating the activity of RNA-binding proteins through methyla
tion. The cDNA for human PRMT1 (HRMT1L2) was recently identified. In this p
aper, we describe the complete genomic organization of the human PRMT1 gene
(GenBank Accession No. AF222689), together with its precise chromosomal lo
calization in relation to other neighboring genes. We have also examined it
s expression in a total RNA panel of 26 human tissues, the BT-474 breast ca
rcinoma cell line, and 16 breast tumors. PRMT1, which spans 11.2 kb of geno
mic sequence on chromosome 19q13.3, is located in close proximity to the IR
F3 and RRAS genes and is transcribed in the opposite direction. It is forme
d of 12 coding exons and 11 intervening introns, and shows structural simil
arity to other PRMT genes. Three PRMT1 isoforms exist as a result of altern
ative mRNA splicing, Amino acid sequence comparison of the splicing variant
s indicates that they are all enzymatically active methyl transferases, but
with different N-terminal hydrophobic regions. PRMT1 expression was detect
ed in a variety of tissues. We have shown that the relative prevalence of a
lternatively spliced forms of PRMT1 is different between normal and cancero
us breast tissues. Although PRMT1 was not found to be hormonally regulated
by steroid hormones in breast cancer cells, our results suggest that two va
riants of PRMT1 are down regulated in breast cancer. (C) 2000 Academic Pres
s.