Biomaterial Database

Alteration of methylation patterns in rat liver histones following administration of ethionine, a liver carcinogen. 1981

R Cox, and M T Tuck

The possible role of alterations of histone methylation by ethionine in the mechanism of ethionine carcinogenesis was studied. In regenerating rat liver, histone synthesis was inhibited by only 20 to 30% with large doses of ethionine (0.75 to 1.0 mg/g body weight). The effect of ethionine on the in vivo methylation of histones was studied by giving 0.5 mg ethionine and [methyl-3H]methionine per g body weight. In vivo methylation of lysine was inhibited by 50%, whereas the arginine methylation was inhibited by 89%. The cellular localization of the methyltransferases and S-adenosyl-L-ethionine may be related to this differential effect. Utilizing an in vitro assay for protein-lysine and protein-arginine methyltransferases, we have demonstrated that the methyl-deficient histones are transported to the nucleus and with time lose their ability to accept methyl groups in vitro.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008239	Lysine	An essential amino acid. It is often added to animal feed.	Enisyl,L-Lysine,Lysine Acetate,Lysine Hydrochloride,Acetate, Lysine,L Lysine
D008297	Male		Males
D008715	Methionine	A sulfur-containing essential L-amino acid that is important in many body functions.	L-Methionine,Liquimeth,Methionine, L-Isomer,Pedameth,L-Isomer Methionine,Methionine, L Isomer
D008745	Methylation	Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)	Methylations
D011484	Protein-Arginine N-Methyltransferases	Enzymes that catalyze the methylation of arginine residues of proteins to yield N-mono- and N,N-dimethylarginine. This enzyme is found in many organs, primarily brain and spleen.	Protein Arginine Methyltransferase,Protein Methylase I,Protein Methyltransferase I,Protein-Arginine N-Methyltransferase,(Myelin Basic Protein)-Arginine N-Methyltransferase,Arginine Methylase,Myelin Basic Protein (Arginine) Methyltransferase,Type I Protein Arginine Methyltransferase,Type I Protein Arginine N-Methyltransferase,Type II Protein Arginine Methyltransferase,Arginine Methyltransferase, Protein,Methyltransferase, Protein Arginine,Protein Arginine N Methyltransferase,Protein Arginine N Methyltransferases,Type I Protein Arginine N Methyltransferase
D011495	Histone-Lysine N-Methyltransferase	An enzyme that catalyzes the methylation of the epsilon-amino group of lysine residues in proteins to yield epsilon mono-, di-, and trimethyllysine.	Protein Lysine Methyltransferase,Protein Methylase III,Protein Methyltransferase III,Histone-Lysine Methyltransferase,Histone Lysine Methyltransferase,Histone Lysine N Methyltransferase,Methyltransferase, Histone-Lysine,Methyltransferase, Protein Lysine,N-Methyltransferase, Histone-Lysine
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D005001	Ethionine	2-Amino-4-(ethylthio)butyric acid. An antimetabolite and methionine antagonist that interferes with amino acid incorporation into proteins and with cellular ATP utilization. It also produces liver neoplasms.
D006657	Histones	Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.	Histone,Histone H1,Histone H1(s),Histone H2a,Histone H2b,Histone H3,Histone H3.3,Histone H4,Histone H5,Histone H7