Biomaterial Database

Amplification of the metallothionein-I gene in cadmium-resistant mouse cells. 1981

L R Beach, and R D Palmiter

Friend leukemia cells resistant to cadmium toxicity were selected. More than 70% of total cysteine incorporation in these cells was into the metal-binding protein, metallothionein. We used cDNA and genomic DNA clones containing the metallothionein-I gene to measure the concentration of its mRNA, the rate of gene transcription, and the number of genes. On a per cell basis, optimally induced, cadmium-resistant cells have a 14-fold more metallothionein-I mRNA, a 6-fold higher rate of metallothionein-I gene transcription, and 6-fold more metallothionein-I genes than do nonresistant cells. Metaphase spreads revealed that the resistant cells are nearly tetraploid and contain, on the average, three very small chromosomes that are absent from non-resistant Friend cells.

UI	MeSH Term	Description	Entries
D007942	Leukemia, Experimental	Leukemia induced experimentally in animals by exposure to leukemogenic agents, such as VIRUSES; RADIATION; or by TRANSPLANTATION of leukemic tissues.	Experimental Leukemia,Experimental Leukemias,Leukemia Model, Animal,Leukemias, Experimental,Animal Leukemia Model,Animal Leukemia Models,Leukemia Models, Animal
D008667	Metalloproteins	Proteins that have one or more tightly bound metal ions forming part of their structure. (Dorland, 28th ed)	Metalloprotein
D008668	Metallothionein	A low-molecular-weight (approx. 10 kD) protein occurring in the cytoplasm of kidney cortex and liver. It is rich in cysteinyl residues and contains no aromatic amino acids. Metallothionein shows high affinity for bivalent heavy metals.	Isometallothionein,Metallothionein A,Metallothionein B,Metallothionein I,Metallothionein II,Metallothionein IIA
D002104	Cadmium	An element with atomic symbol Cd, atomic number 48, and atomic weight 112.41. It is a metal and ingestion will lead to CADMIUM POISONING.
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
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D004351	Drug Resistance	Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.	Resistance, Drug
D005622	Friend murine leukemia virus	A strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) producing leukemia of the reticulum-cell type with massive infiltration of liver, spleen, and bone marrow. It infects DBA/2 and Swiss mice.	Friend Virus,Rowson-Parr Virus,Rowson Parr Virus,Virus, Friend,Virus, Rowson-Parr
D005784	Gene Amplification	A selective increase in the number of copies of a gene coding for a specific protein without a proportional increase in other genes. It occurs naturally via the excision of a copy of the repeating sequence from the chromosome and its extrachromosomal replication in a plasmid, or via the production of an RNA transcript of the entire repeating sequence of ribosomal RNA followed by the reverse transcription of the molecule to produce an additional copy of the original DNA sequence. Laboratory techniques have been introduced for inducing disproportional replication by unequal crossing over, uptake of DNA from lysed cells, or generation of extrachromosomal sequences from rolling circle replication.	Amplification, Gene
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia