title: Human normal T lymphocytes and lymphoid cell lines do express alternative splicing variants of human telomerase reverse transcriptase (hTERT) mRNA.
abstract: Alternative splicing of telomerase reverse transcriptase (hTERT) mRNA is known to contribute to regulation of telomerase activity in normal and cancerous cells, however, previous studies indicated that normal human T and B cells exhibited constitutive expression of full-length hTERT mRNA without splicing variants and that activation of telomerase upon stimulation of the cells was due to the shuttling of hTERT protein from cytoplasm to nucleus [Proc. Natl. Acad. Sci. USA 96 (1999) 5147; J. Immunol. 166 (2001) 4826]. We found that typical variants of hTERT mRNA were widespread in human lymphocyte-derived cell lines and normal stimulated T cells. In activated T cells, induction of the full-length hTERT mRNA was coupled with increased hTERT protein expression and telomerase activity. Collectively, human normal and malignant lymphocytes, like other human cells, express splicing variants of hTERT mRNA and require transcriptional activation of the hTERT gene to acquire telomerase activity.
authors.affiliation: Department of Medicine, Division of Haematology, Karolinska University Hospital Solna and Karolinska Institutet, SE-171 76 Stockholm, Sweden.
authors.forename: Marit
authors.initials: M
authors.lastname: Jalink
authors.forename: Zheng
authors.initials: Z
authors.lastname: Ge
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.forename: Magnus
authors.initials: M
authors.lastname: Björkholm
authors.forename: Astrid
authors.initials: A
authors.lastname: Gruber
authors.forename: Dawei
authors.initials: D
authors.lastname: Xu
mesh_terms: D017398:Alternative Splicing; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015153:Blotting, Western; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D019169:Jurkat Cells; D008221:Lymphoid Tissue / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D019098:Telomerase / Q000235:genetics* / Q000378:metabolism
chemical_list: D016895:Culture Media, Serum-Free; D007527:Isoenzymes; C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; C509186:TERT protein, human; D019098:Telomerase