TY - JOUR
T1 - Differential gene expression of human telomerase-associated protein hTERT and TEP1 in human hematopoietic cells
AU - Uchida, Naoyuki
AU - Otsuka, Teruhisa
AU - Shigematsu, Hirokazu
AU - Maeda, Motoi
AU - Sugio, Yasuhiro
AU - Itoh, Yoshikiyo
AU - Niho, Yoshiyuki
N1 - Funding Information:
We thank Kiyoka Funatsu for assistance with telomerase assays. This work was supported by Grant-in-Aid 5396 from the Ministry of Education of Japan. The contributions of all authors are listed in below; Naoyuki Uchida (1,2,3,4,5,6,7,10), Teruhisa Otsuka (4,5,6,8,9), Hirokazu Shigematsu (1,2), Motoi Maeda (2,6), Yasuhiro Sugio (2,6), Yoshikiyo Itoh (2,6), Yoshiyuki Niho (2,5,8,9). N. Uchida assisted in data collection and analysis, contributed to the concept, design and drafted the paper, provided critical revision, gave final approval, provided statistical expertise and study materials. T. Otsuka provided administrative support and funding, gave critical revision, provided study materials and gave final approval. H. Shigematsu contributed to the concept and design and helped with data analysis. M. Maeda, Y. Sugio, and Y. Itoh provided study materials and assisted with data interpretation. Y. Niho provided administrative support, obtained funding, gave both critical revision and final approval of the article.
PY - 1999/12
Y1 - 1999/12
N2 - The maintenance of telomere length is crucial for the survival of cells. Recently, genes for proteins that consist of human telomerase have been cloned and the results have indicated a close relationship between telomerase activity and its gene expression. We studied the mRNA expression of the telomerase-associated genes, hTERT and TEP1, in hematopoietic cells in order to clarify the relation between them and telomerase activity using semiquantitative RT-PCR. In polymorphonuclear cells and monocytes isolated from peripheral blood, which had no detectable telomerase activity, no hTERT mRNA expression was seen. On the other hand, lymphocytes and CD34-positive cells both demonstrated hTERT mRNA expression. TEP1 mRNA was detected in all samples, showing no differential expression. We then assessed hTERT and TEP1 mRNA expression in CD34-positive cells cultured in vitro with growth factors. After 4 weeks of culture, all the cells showed myeloid differentiation and the telomerase activity was downregulated. hTERT mRNA was expressed in CD34-positive cells, but was downregulated in 4-week-cultured cells. TEP1 showed no apparent differential expression. We conclude that hTERT mRNA expression is downregulated in accordance with telomerase downregulation during the course of myeloid differentiation, which suggests that it plays a crucial role in the expression of enzyme activity, while TEP1 has a much smaller role to play, if any. Copyright (C) 1999 Elsevier Science Ltd.
AB - The maintenance of telomere length is crucial for the survival of cells. Recently, genes for proteins that consist of human telomerase have been cloned and the results have indicated a close relationship between telomerase activity and its gene expression. We studied the mRNA expression of the telomerase-associated genes, hTERT and TEP1, in hematopoietic cells in order to clarify the relation between them and telomerase activity using semiquantitative RT-PCR. In polymorphonuclear cells and monocytes isolated from peripheral blood, which had no detectable telomerase activity, no hTERT mRNA expression was seen. On the other hand, lymphocytes and CD34-positive cells both demonstrated hTERT mRNA expression. TEP1 mRNA was detected in all samples, showing no differential expression. We then assessed hTERT and TEP1 mRNA expression in CD34-positive cells cultured in vitro with growth factors. After 4 weeks of culture, all the cells showed myeloid differentiation and the telomerase activity was downregulated. hTERT mRNA was expressed in CD34-positive cells, but was downregulated in 4-week-cultured cells. TEP1 showed no apparent differential expression. We conclude that hTERT mRNA expression is downregulated in accordance with telomerase downregulation during the course of myeloid differentiation, which suggests that it plays a crucial role in the expression of enzyme activity, while TEP1 has a much smaller role to play, if any. Copyright (C) 1999 Elsevier Science Ltd.
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U2 - 10.1016/S0145-2126(99)00149-6
DO - 10.1016/S0145-2126(99)00149-6
M3 - Article
C2 - 10613358
AN - SCOPUS:0032745120
VL - 23
SP - 1127
EP - 1132
JO - Leukemia Research
JF - Leukemia Research
SN - 0145-2126
IS - 12
ER -
