Expression of mouse telomerase catalytic subunit in embryos and adult tissues.
Telomerase is a ribonucleoprotein complex that elongates telomeres, allowing the stable maintenance of chromosomes during multiple cell divisions. Here, we describe the isolation and characterization of the catalytic subunit of mouse telomerase, mTERT (mouse telomerase reverse transcriptase), an essential protein component of the telomerase complex. During embryonic development, mTERT mRNA is abundantly expressed in the whole embryo, especially in regions of intense proliferation. We found that the mTERT mRNA expression in both embryonic and adult tissues is independent of the essential RNA component of telomerase, mTR, and therefore, of the formation of active telomerase complexes. mTERT protein is present exclusively in tissues with telomerase activity, such as testis, spleen, and thymus. mTERT protein is barely detectable in the thymus of mTR-/- mice, suggesting that mTERT protein stability in this tissue may depend on the actual assembly of active telomerase complexes. Finally, we found that mouse and human telomerase catalytic subunit is located in the cell nucleus, and its localization is not regulated during cell cycle progression.
Department of Immunology and Oncology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Campus de Cantoblanco, Madrid 28049, Spain.
L
L
Martín-Rivera
E
E
Herrera
J P
JP
Albar
M A
MA
Blasco
D000818:Animals; D000906:Antibodies / Q000276:immunology; D001483:Base Sequence; D002384:Catalysis; D003001:Cloning, Molecular; D017931:DNA Primers; D004268:DNA-Binding Proteins; D004622:Embryo, Mammalian / Q000201:enzymology*; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D012313:RNA; D019098:Telomerase
D000906:Antibodies; D017931:DNA Primers; D004268:DNA-Binding Proteins; D011506:Proteins; C422952:telomerase RNA; D012313:RNA; D019098:Telomerase