Transcription - ATP amounts?

[shefv]

I understand the process of transcription - but exactly how many ATP molecules are used in this process?

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[desperadoflakes]

Umm..0 I guess? I would think the process would consume ATP

 

[amy_k]

ATP is used for initiation, elongation and termination of transcription: energy from ATP hydrolysis is required in 2 or 3 steps of initiation including opening of the promoter region and promoter binding, and converting RNA pol II from closed to open complex, also helicase activity and termination factors require energy from phosphodiester bonds.

All in all it appears to require 4 ATP per transcript on average (2 for initiation, 1 for elongation, and 1 for termination). Energy from GTP hydrolysis is also used in transcription.

 

[amy_k]

Here is the most up to date article i could find addressing the specific energy cost of protein synthesis as a whole http://m.mbe.oxfordjournals.org/content/22/6/1365.full.pdf