How is the rate of transcription influenced by temperature?
If your looking at transcription then your talking about RNA POLYMERASE.

And there are many variants. Here's a good Nature paper that discusses temperature and RNA Pol

http://www.nature.com/ncomms/journal/v1/n6/full/ncomms1076.html

And another:

http://www.ncbi.nlm.nih.gov/m/pubmed/12729734/

I couldn't get full access to this JBC paper but I think the answer would be clearly in here, prob worth a look

M. Chamberlin and J. Ring. Characterization of T7-specific ribonucleic acid polymerase. 1. General properties of the enzymatic reaction and the template specificity of the enzyme. J Biol Chem. 248: 2235-44 (1973)