Gene expression and transcription factors - (Jan/30/2015 )

Hi,

I have a question about gene expression and transcription factors.

Do transcription factors drive all of the gene expression changes or is can gene expression change by things other than transcription factors? 

I will appreciate any insight. 

Thanks, 

John. 

gene expression is controlled by several things:

1. Transcription factors (repressors and activators)

2. DNA epigenetic changes

3. Histone epigenetic changes

4. Enhancers (long-range)

5. Silencers

In addition, once a genomic transcript is generated, it can be spliced, truncated, degraded in so many ways that it changes eventual protein levels. Also, protein can be controlled in several ways (ribosomal processing, tagging for degradation etc) during and after translation. 

And this is very basic idea, there is a lifetime of complexity to talk about here.