Cloning and expression of the reverse transcriptase component of pufferfish (Fugu rubripes) telomerase.
The enzyme telomerase is essential for maintaining the ends of linear chromosomes. It plays an important role in cell proliferation, differentiation, tumorigenesis and aging. Telomerase is composed of an RNA subunit (TR) and a reverse transcriptase catalytic subunit (TERT). We report here the cloning and characterization of the gene encoding the TERT subunit from a teleost fish, Fugu rubripes. This is the first fish TERT gene to be cloned. The fugu TERT (fTERT) gene comprises of 16 exons and 15 introns similar to the human TERT (hTERT), and encodes a 1074 amino acid protein. The fTERT protein showed 33% to 35% sequence identity to other vertebrate TERTs, and contained all the signature motifs of the TERT family. Analysis of the promoter region of fTERT showed the presence of several transcription factor binding sites (E2F-1, E-box, ER, Sp1 and USF sites) in common with the hTERT promoter, and whose binding factors are known to regulate hTERT. The fTERT gene is expressed in a variety of tissues, with high expression detected in the gill, testis, and ovary. fTERT expression was detected in an immortalized fugu eye-derived cell line. The level of expression was found to be higher in actively dividing cells and reduced at quiescence, suggesting cell cycle regulation of TERT and possibly telomerase activity, in this cell line.
Yap
Wai Ho
WH
Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore.
Yeoh
Elizabeth
E
Brenner
Sydney
S
Venkatesh
Byrappa
B
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D019098:Telomerase / Q000235:genetics*; D023721:Tetraodontiformes / Q000235:genetics*
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C509186:TERT protein, human; D019098:Telomerase