snrna

DNA transcription

snRNA and nuclear proteins form snRNP’s [pronounced like snurps] that join protein complexes to form the complex molecular machine called splicisomes which remove introns from transcribed Pre-mRNA

Transcription factors bind to a region of the DNA called the promoter, which identifies the start of the gene, which strand is to be copied, and the direction in witch it is copied.

RNA polyemerase then binds to the transcription factors and promoters

(in prokaryotes there are no transcription factors so RNA polymerase binds directly to the promoter)

RNA polymerase unwinds DNA then aranges the complimentary nucleotides 

THE DIRECTION OF SYNTHESIS IS 5’ TO 3’

Then transcription stops:

in prokaryotes there is a termination sequence in the DNA that indicates where it will stop

In eukaryotes transcription stops after the polyadenylation signal