Anon01/24/26, 14:21No.16898140
Telomeres were first recognized conceptually in the 1930s by
Hermann Muller and Barbara McClintock, who observed that chromosome ends possess unique, protective structures that prevent fusion and degradation. However, their molecular structure and function were discovered in the late 1970s and 1980s by Elizabeth Blackburn, along with Carol Greider and Jack Szostak, who identified them as repetitive DNA sequences (e.g., TTAGGG in humans) that cap linear chromosomes, earning them the 2009 Nobel Prize.
Description of TelomeresStructure: Telomeres are specialized, non-coding, repetitive DNA sequences found at the extreme ends of eukaryotic chromosomes.
Function: They act as protective caps (similar to shoelace tips) that prevent chromosomes from fusing with each other or being recognized as broken DNA, which would otherwise trigger cell death or harmful mutations.
The "End-Replication" Problem: Because standard DNA polymerase cannot copy the very tip of a linear chromosome, telomeres shorten with every cell division.
Cellular Aging: When telomeres become too short, the cell can no longer divide, leading to cellular senescence (aging) or death.
Telomerase: The enzyme telomerase, discovered by Blackburn and Greider, can lengthen telomeres, keeping them long in specific cells like stem cells and, unfortunately, cancer cells.In short, telomeres are essential protective caps for DNA that shorten over time, acting as a "molecular clock" for cellular aging