The button will toggle spinning on and off.

Leucine zippers can be found in transcription factors.

How do the transcription factors interact with each other?

These transcription factors form dimers and bind to pseudo-palidromic
DNA sequences (each monomer binds to a half-site). The DNA recognition
domain on each monomer is closer to the N-terminal while the leucine
zipper domain is closer to the C-terminal. The location of the two
domains allows a large number of DNA sequences to be recognized by
only a few monomers because monomers form leucine zippers as
homodimers or heterodimers.

Huh? Let's have an example.

Say monomer A recognizes the half-site 5'-CCAT-3' while monomer B
recognizes the half-site 5'-TTAG-3'. A homodimer of monomer A would bind
to the following sequence:

5'-CCAT...ATGG-3'
3'-GGTA...TACC-5'.

A homodimer of monomer B would bind to

5'-TTAG...CTAA-3'
3'-AATC...GATT-5'.

If a heterodimer of monomer A and B formed it would bind to

5'-CCAT...CTAA-3'
3'-GGTA...GATT-5'.

If another monomer type were added to A and B, even more combinations
could be made and more DNA sites would be recognized.

The ability of transcription factors to form heterodimers allows a cell
to use less proteins to regulate transcription because the cell does
not need to make unique proteins for every DNA regulatory sequence.

The rest of this website is best seen when browers is as large as possible.

Click next for specific leucine zipper transcription factors.

Branden, C., & Tooze, J. (1999). Introduction to Protein Structure (2nd ed.). New York: Garland Publishing.