intron
Học thuậtThân thiện
Definition
Noun: A segment of a DNA or RNA molecule in a eukaryotic organism's gene that does not code for a protein and is removed during the process of creating mature messenger RNA (mRNA).
Usage
The term "intron" is used in the fields of genetics and molecular biology to describe non-coding sequences within a gene. It contrasts with "exon," which is the coding sequence. Introns are transcribed into precursor mRNA but are spliced out before the mRNA is translated into a protein.
Examples
- In the process of gene expression, introns are removed from the RNA transcript.
- The gene contains several introns interspersed between the exons.
- Scientists study intron sequences to understand evolutionary relationships.
Advanced Usage
- Intron retention: A regulatory mechanism where an intron is not spliced out of the mRNA, which can affect the resulting protein or lead to its degradation.
- Group I/II intron: Self-splicing introns that can catalyze their own removal from an RNA molecule without the need for a protein enzyme.
Variants and Related Words
- Exon (noun): The sequence of DNA in a gene that codes for protein and remains in the mature mRNA after splicing.
- Splicing (noun): The process by which introns are removed from precursor mRNA and exons are joined together.
Synonyms
- Intervening sequence
- Non-coding region (within a gene)
Antonyms
- Exon
- Coding sequence
Noun
- sequence of a eukaryotic gene's DNA that is not translated into a protein