What are Telomeres?

Telomere (English name: Telomere) is a small piece of DNA-protein complex that exists at the end of linear chromosomes of eukaryotic cells. It forms a special "hat" structure with telomere binding proteins, which is used to maintain the integrity of chromosomes And control the cell division cycle. Telomeres, centromeres, and origins of replication are the three major factors that keep chromosomes intact and stable.

Telomere

Telomere (English name: Telomere) is present in

Telomeres are short, multi-repeated non-transcribed sequences (TTAGGG) and some binding proteins make up a special structure. In addition to providing a buffer for non-transcribed DNA, it can also protect the ends of chromosomes from fusion and degradation. It plays an important role in protecting and controlling cell growth and longevity, and is closely related to apoptosis, cell transformation and immortalization. when

Stabilize the structure of chromosome ends, prevent inter-chromosome end connections, and compensate for the gaps caused by the elimination of RNA primers at the 5 'end of the lag strand.

Telomere DNA is simple DNA

When scientists looked for the gene that caused cell death, they found a substance called telomeres that exists on the top of chromosomes. The telomere itself does not have any cryptographic function, it is like a tall hat placed on the chromosome head.

In new cells, each time a cell divides, the telomeres on the top of the chromosome are shortened. When the telomeres can no longer be shortened, the cell cannot continue to divide. At this time, the cell reached the limit of 100 times that is generally thought to divide and began to die. Therefore, telomeres are regarded by scientists as the "clock of life."

Scientists began to study again

Maintenance of telomere length is a prerequisite for continued cell division ^[2]

The existence of highly homologous sequences in the chromosomal subtelomere region results in abnormal homologous recombination during meiosis, which results in minor deletions, duplications, or chromosomal translocations in this region. This is called abnormal chromosomal subtelomere recombination. Patients with this disease are mainly manifested with different degrees of mental retardation, accompanied by growth retardation and deformities of various organs and systems. Trisomy syndrome.

Caption: Telomeres are like a DNA cap, protecting important DNA information from being lost (Credit: ALFRED PASIEKA / SCIENCE PHOTO LIBRARY) ^[3]