Expression of Telomerase mRNA in Nile Tilapia Tissues

Telomeres are repeated sequences of DNA that constitute the ends of chromosomes. Telomere length can be maintained by the activity of the ribonucleoprotein telomerase. Telomerase expression is readily observed in human stem cells and germ cells, but the gene is turned off in most normal human somatic tissues. In contrast, telomerase activity has been observed in tissues of fishes, including rainbow trout and Japanese medaka. It is unknown whether telomerase is constitutively expressed in Nile tilapia, a freshwater fish of interest because it is one of the most common farm-raised fish for human consumption. In recent years, a novel virus named tilapia lake virus (TiLV) was discovered and found to be the cause of mass die-offs of tilapia populations. In this study, we designed primers and used them to perform reverse transcriptase polymerase chain reaction (RT-PCR) analysis of telomerase expression in eleven tilapia organs. All eleven organs showed telomerase expression, with highest expression in the kidney and intestine. Our study is the first to show that telomerase is constitutively expressed in a variety of adult Nile tilapia tissues