Differential gene expression is the process by which genes are turned on or off in different cell types, at different stages of development, or in response to environmental changes.
This is the broad term for how cells control which genes are expressed and when. It's like deciding who has access to the light switches in our analogy.
These proteins bind to specific DNA sequences and control the transcription of genetic information from DNA to mRNA. They're like the individual switches that turn each light (gene) on or off.
This refers to changes in gene expression that don't involve alterations to the underlying DNA sequence. It's like putting a dimmer switch on some rooms' lights - it doesn't change what bulbs are there, just how brightly they shine.