PUBLICATION
Molecular Cloning and Characterization of the Zebrafish (Danio rerio) Telomerase Catalytic Subunit (Telomerase Reverse Transcriptase, TERT)
- Authors
- Lau, B.W., Wong, A.O., Tsao, G.S., So, K.F., and Yip, H.K.
- ID
- ZDB-PUB-071227-19
- Date
- 2008
- Source
- Journal of molecular neuroscience : MN 34(1): 63-75 (Journal)
- Registered Authors
- Keywords
- Telomerase, Telomerase reverse transcriptase, Zebrafish, Rapid amplification of cDNA ends, TRAP assay, Cloning, Immunohistochemistry, RT-PCR
- MeSH Terms
-
- Amino Acid Sequence/genetics
- Animals
- Base Sequence/genetics
- Brain/cytology
- Brain/metabolism
- Cell Differentiation/genetics
- Cloning, Molecular
- Conserved Sequence
- Molecular Sequence Data
- Molecular Weight
- Neurons/metabolism
- Phylogeny
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Retina/cytology
- Retina/metabolism
- Sequence Homology, Amino Acid
- Telomerase/genetics
- Telomerase/isolation & purification
- Telomerase/metabolism*
- Zebrafish/genetics*
- Zebrafish/growth & development
- Zebrafish/metabolism
- Zebrafish Proteins/genetics
- Zebrafish Proteins/isolation & purification
- Zebrafish Proteins/metabolism*
- PubMed
- 18157659 Full text @ J. Mol. Neurosci.
Citation
Lau, B.W., Wong, A.O., Tsao, G.S., So, K.F., and Yip, H.K. (2008) Molecular Cloning and Characterization of the Zebrafish (Danio rerio) Telomerase Catalytic Subunit (Telomerase Reverse Transcriptase, TERT). Journal of molecular neuroscience : MN. 34(1):63-75.
Abstract
Telomerase is an enzyme composed of a catalytic subunit (TERT) and RNA template (TR), which specifically elongates telomeres and prevents cellular senescence. Although telomerase cannot be detected in most human somatic tissues, including the nervous system, it can be detected in teleost tissues. To facilitate the investigation of telomerase function in the teleost visual system, the coding sequence of zebrafish TERT is revealed and cloned. Immunoblot, immunohistochemistry, reverse transcription polymerase chain reaction (RT-PCR), and telomeric repeats amplification protocol (TRAP) assay are used to assess the expression of telomerase at mRNA, protein, and functional levels in zebrafish retina. Based on the amino acid sequence of mouse TERT, a full-length telomerase reverse transcriptase cDNA of zebrafish has been isolated and cloned. The deduced protein sequence contains 1,091 amino acid residues and a predicted molecular mass of 126 kDa. Multiple alignment shows that the protein sequence contains the conserved motifs and residues found in TERT of other species. RT-PCR and TRAP assay has detected TERT mRNA expression and telomerase activity, respectively, in all tissues examined, including the retina and the brain. The presence of telomerase activity indicates that a fully functional form of telomerase can be found in the retina. Immunohistochemistry reveals that most neurons in zebrafish retina express TERT in the cell nucleus. The presence of telomerase in different tissues may be associated with the indeterminate growth of teleost. However, teleost retinal neurons are post-mitotic and do not further divide under normal situation. The expression of telomerase activity and TERT in retina implies that telomerase has functions other than the elongation of telomere. These findings could provide new insights on telomerase function in the nervous system.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping