VCAC: Molecular Processes: mRNA Splicing: Advanced Look: Primary Transcript

Questions? Comments? Please contact Dr. Phillip McClean or Christina Johnson.

Flythrough Tour

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CELLULAR PROCESSES

Atp Synthase

Electron Transport Chain

Protein Trafficking

Protein Modification

Protein Recycling

Constitutive Secretion

Regulated Secretion

Mitochondrial Protein Transport

Photosynthesis

Photosystem II

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MOLECULAR PROCESSES

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HOME > mRNA splicing > ADVANCED LOOK > 1.) Primary transcript

mRNA Splicing: Advanced Look --> 1.) Primary Transcript

When mRNA is ready for splicing, it is known as a primary transcript. Clicking on each of the thumbnail images will bring up a larger, labeled version of the described scene.

To see the Flash movie for the following sequence of images, click here.

	The primary transcript contains sequences known as exons and introns.
	This primary transcript contains two exons and one intron. Here we see exon 1.
	Here we see the intron. Introns contain sequences that guide the splicing process. These include a 5' GU (GT in DNA) sequence...
	...an A branch site located near a pyrimidine-rich region...
	...and a 3' AG sequence.
	Exon 2 is found on the opposite end of the intron. The 3' end of the primary transcript also contains the poly-A tail added during mRNA processing.

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