Lecture13:mRNA Processing

Flashcards about mRNA processing in eukaryotic cells, transcription, translation, and introns.

mRNA processing

The process by which the mRNA produced by transcription is processed in eukaryotic cells.

Transcription

The process of making mRNA from DNA.

Translation

The process of using mRNA information to build a polypeptide.

Pre-mRNA

The initial RNA transcript before it has been processed.

mRNA

The mature RNA transcript after it has been processed, which is translated in the cytoplasm.

5' cap

A modified guanine (GTP) added to the 5' end of mRNA during RNA processing to protect it and assist in ribosome attachment.

Poly-A tail

A sequence of multiple adenosine monophosphates (A's) added to the 3' end of mRNA during processing to protect it, signal its export from the nucleus, and assist in ribosome attachment.

Introns

Non-coding sequences of DNA that are transcribed into pre-mRNA, but are then cut out and degraded in the nucleus during RNA splicing.

Exons

Coding sequences of DNA that are transcribed and spliced together to form the mature mRNA that is translated into protein.

Splicing

The process of cutting out introns and joining exons together to form the mature mRNA.

Spliceosome

A large structure made of proteins and RNA that is responsible for splicing introns out of pre-mRNA.

Alternative splicing

A process by which different combinations of exons are spliced together, resulting in multiple different but related polypeptides from a single gene.