Definition

Noun: An enzyme present in eukaryotic cells that is capable of adding specific DNA sequences (telomeres) to the ends of chromosomes, counteracting the shortening that typically occurs during cell division.

Usage

Telomerase is a specialized enzyme. Its primary function is to maintain the length of telomeres, which are protective caps at the ends of chromosomes. This activity is crucial for cellular longevity and is particularly active in certain cell types, such as stem cells and germ cells.

Examples

• Noun:
  • The activity of telomerase helps prevent the progressive shortening of chromosomes.
  • Researchers are studying telomerase to understand its role in aging and cancer.
  • A lack of telomerase activity in most somatic cells is linked to cellular aging.

Advanced Usage

• "telomerase activity": Refers to the measurable function or presence of the telomerase enzyme.
  • High telomerase activity is often found in immortalized cell lines.
• "telomerase reverse transcriptase (TERT)": The catalytic protein subunit of the telomerase enzyme complex.
  • Mutations in the TERT gene can affect telomerase function.

Variants and Related Words

• Telomere (noun): The repetitive nucleotide sequence at each end of a chromosome, which protects it from deterioration.
• Telomeric (adjective): Relating to or characteristic of a telomere.
  • Telomeric DNA shortens with each cell division in the absence of telomerase.

Synonyms

• Terminal transferase (in a broad, functional context, though this is a less specific term).

Notes on Meaning

The term "telomerase" specifically denotes the enzyme complex. It is distinct from the structure it maintains (the telomere) and the process it is involved in (telomere elongation). Its discovery was fundamental to understanding cellular aging and immortality.

Noun

1. an enzyme in eukaryotic cells that can add telomeres to the ends of chromosomes after they divide