Transcription

​WHAT IS TRANSCRIPTION?

DNA transcription is a process that involves transcribing genetic information from DNA to RNA. The transcribed DNA message, or RNA transcript, is used to produce proteins.

There are three main steps to the process of DNA transcription :

• Chain initiation / RNA Polymerase Binds to DNA

DNA is transcribed by an enzyme called RNA polymerase. Specific nucleotide sequences tell RNA polymerase where to begin and where to end. RNA polymerase attaches to the DNA at a specific area called the promoter region and forms closed complex. After this, DNA unwinds at promoter to form open complex which is required for chain initiation.

• Chain Elongation

Topoisomerases unwind the DNA strand and allow RNA polymerase to transcribe only a single strand of DNA into a single stranded RNA polymer called messenger RNA (mRNA).

• Chain Termination

RNA polymerase moves along the DNA until it reaches a terminator sequence. At that point, RNA polymerase releases the mRNA polymer and detaches from the DNA.

Two types of termination mechanisms :

1. Intrinsic termination

2. Termination involves rho (p) protein

HERE'S THE FULL VIDEO OF TRANSCRIPTION PROCESS !