DNA Transcription

Initiation: 

Initiation complex:
-Transcription factors recognize and locate the TATA box
-TATA box is the promoter region

• RNA polymerase II unwinds and opens a section of the double helix
• RNA polymerase II binds to the promoter region 
• RNA transcription begins in the coding strand of DNA with RNA polymerase II

Elongation:

• RNA pol II synthesizes a strand of mRNA (complimentary to template strand)
• "T"is replaced with "U" in the mRNA strand
• RNA pol II works in the direction of 5' to 3'
• mRNA is anti parallel with the DNA Template strand (Antisense), and is similar to the DNA Coding strand (Sense)
• transcription goes from upstream (promoter) to downstream (terminator)

Termination:

• Transcription stops and RNA pol II detaches from the DNA strand when it reaches the "AAA UAA" signal
• pre-mRNA becomes RNA by the addition of a G-cap to the 5' end and the addition of a 3'poly-A tail to the 3' end
• Intron sections of the mRNA are cut out by the spliceosome and the Exons are joined together 
• Spliceosome are assembled from snRNP which are proteins that contain snRNA who recognize the Intron segements