The chicken telomerase reverse transcriptase (chTERT): molecular and cytogenetic characterization with a comparative...

Area of Science:

• Molecular Biology
• Genetics
• Comparative Genomics

Background:

• Telomerase activity is crucial for maintaining chromosome ends (telomeres).
• Telomerase comprises RNA and a reverse transcriptase component.
• Understanding telomerase diversity aids in comprehending telomere maintenance mechanisms across species.

Purpose of the Study:

• To elucidate the molecular and cytogenetic characteristics of the chicken telomerase reverse transcriptase (chTERT) gene and protein.
• To compare chTERT with its human counterpart (hTERT) and other vertebrate TERTs.

Main Methods:

• Analysis of TERT mRNA sequence and protein translation from chicken gastrula embryos.
• Sequence identity comparison between chicken and human TERT proteins.
• Gene mapping of chicken TERT to its chromosomal location.
• Identification and comparison of transcription factor binding motifs in the promoter regions.

Main Results:

• Chicken TERT (chTERT) mRNA is 4497 bp, encoding a 1346 amino acid protein.
• chTERT shares 45% amino acid identity with human TERT (hTERT).
• chTERT exhibits a significantly longer N-terminal flexible linker region compared to hTERT.
• Chicken TERT maps to chromosome 2q21, near an interstitial telomere site.
• Shared and unique transcription factor binding motifs were identified in the chTERT promoter compared to hTERT.

Conclusions:

• The distinct features of chTERT, particularly its larger protein size, offer insights into structure-function relationships.
• Comparative analysis of TERT regulation and function in vertebrates is facilitated by these findings.
• This research contributes to understanding the diverse roles of the telomere clock mechanism in different species.