TY - JOUR
T1 - Identification and characterization of sea squirt telomerase reverse transcriptase
AU - Li, Yang
AU - Yates, Joel A.
AU - Chen, Julian
N1 - Funding Information:
We are grateful for Guoliang Li's assistance on predicting the translation initiation site of the C. intestinalis TERT gene. We also thank Dr. William Smith (U.C. Santa Barbara Ascidian Stock Center) for providing genomic DNA and cDNA of C. savignyi. We are grateful to Drs. Mary Armanios and Tien-Hsien Chang, and lab members for critical reading of and helpful comments on the manuscript. This work was supported by an NSF CAREER Award to JLC.
PY - 2007/10/1
Y1 - 2007/10/1
N2 - Telomerase is essential for maintaining telomere length and chromosome stability in most eukaryotic organisms. The telomerase ribonucleoprotein complex consists of two essential components, the catalytic telomerase reverse transcriptase protein (TERT) and the intrinsic telomerase RNA. The sea squirts, as urochordates, occupy a key position in the phylogenetic tree of the chordates: they diverged from the other chordates just before the lineage of vertebrates, and thus provide special insight into the origin and evolution of vertebrate genes. Here, we report the cloning and characterization of TERT genes from two sea squirts, Ciona intestinalis and Ciona savignyi. The C. intestinalis TERT (CinTERT) gene encodes 907 amino acids and consists of 17 exons, which are similar to vertebrate TERT genes. The C. savignyi TERT (CsaTERT) gene encodes 843 amino acids, but surprisingly does not contain any introns. Both Ciona TERTs contain all of the reverse transcriptase (RT) motifs (1, 2, A, B, C, D, and E) that are typically present in telomerase and viral RTs. Interestingly, the alignment of Ciona and vertebrate TERT sequences reveals a previously unknown motif, named motif 3, located between motifs 2 and A. The Ciona TERT gene is expressed in all tissues analyzed except the brain and heart. This is the first report of the TERT gene in invertebrate chordates.
AB - Telomerase is essential for maintaining telomere length and chromosome stability in most eukaryotic organisms. The telomerase ribonucleoprotein complex consists of two essential components, the catalytic telomerase reverse transcriptase protein (TERT) and the intrinsic telomerase RNA. The sea squirts, as urochordates, occupy a key position in the phylogenetic tree of the chordates: they diverged from the other chordates just before the lineage of vertebrates, and thus provide special insight into the origin and evolution of vertebrate genes. Here, we report the cloning and characterization of TERT genes from two sea squirts, Ciona intestinalis and Ciona savignyi. The C. intestinalis TERT (CinTERT) gene encodes 907 amino acids and consists of 17 exons, which are similar to vertebrate TERT genes. The C. savignyi TERT (CsaTERT) gene encodes 843 amino acids, but surprisingly does not contain any introns. Both Ciona TERTs contain all of the reverse transcriptase (RT) motifs (1, 2, A, B, C, D, and E) that are typically present in telomerase and viral RTs. Interestingly, the alignment of Ciona and vertebrate TERT sequences reveals a previously unknown motif, named motif 3, located between motifs 2 and A. The Ciona TERT gene is expressed in all tissues analyzed except the brain and heart. This is the first report of the TERT gene in invertebrate chordates.
KW - Chordate
KW - Invertebrate
KW - TERT
KW - Telomere
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U2 - 10.1016/j.gene.2007.05.013
DO - 10.1016/j.gene.2007.05.013
M3 - Article
C2 - 17601686
AN - SCOPUS:34548022346
SN - 0378-1119
VL - 400
SP - 16
EP - 24
JO - Gene
JF - Gene
IS - 1-2
ER -