The Role of Telomere in Humans

INTRODUCTION In the 16th century, rumors about young fountains spread like wildfires. Immortal ideas and timeless young people have fascinated many aggressive and young adventurers. Most eukaryotic cells are affected by a biological process called aging. The effects of aging include the onset of illness, illness, and ultimate death. The fear of death, this ultimate existence has fascinated many people to pursue longevity. So how do we put off our life? Where is this "youth"?

To help you understand the role of telomere in the human body, it is helpful to review some basic biology. All tissues of the human body are composed of a single cell. These cells contain chromosomes in their nucleus. Chromosomes are packages that contain most of DNA - genetic instructions tell the cell what to do. Telomere is thought to have several uses in human cells. First, telomeres form the end caps of chromosomes. Without them, the body can not know the end of the chromosome. It treats them as "broken" DNA fragments and attempts to repair them by connecting them to other chromosomes. Through telomere, the body can distinguish between the end of one chromosome and the beginning of another chromosome

Some noncoding DNA sequences function structurally in the chromosome. Telomeres and centromeres usually contain few genes, but are important for chromosomal function and stability. The abundant form of noncoding DNA in humans is a pseudogene, which is a copy of the gene prohibited by mutation. Although these sequences are usually merely molecular fossils, they can occasionally serve as primitive genetic material to create new genes through gene duplication and branching.

Telomeres are oligonucleotide repeats of chromosomal end DNA. In humans, these base repeats are TTAGGG and prevent the loss of DNA encoding the gene in incomplete DNA replication. Therefore, a small amount of DNA is lost after each division, and the telomeres are shortened. Among constantly dividing cells, the most prominent is the germ cell, which requires an enzyme to replace the length of the DNA lost by replication in order to continue dividing. Telomerase is an enzyme that adds RNA nucleotides to shortened telomere. Since Alexey Olovnikov proposed the hypothesis in 1971, telomerase has been considered as an important factor in the process of tumor cell division and aging. This review summarizes the role of telomerase in various cell types, the effect of telomerase concentration on replicative capacity, and the relationship with tumor cells.

Restimulation of telomerase production in adult stem cells and mitotic cells is an important factor in tumor cell production