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413  structures 1464  species 0  interactions 10541  sequences 134  architectures

Family: bZIP_2 (PF07716)

Summary: Basic region leucine zipper

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

This is the Wikipedia entry entitled "BZIP domain". More...

BZIP domain Edit Wikipedia article

bZIP transcription factor
CREB (top) is a transcription factor capable of binding DNA via the bZIP domain (bottom) and regulating gene expression.

The Basic Leucine Zipper Domain (bZIP domain) is found in many DNA binding eukaryotic proteins. One part of the domain contains a region that mediates sequence specific DNA binding properties and the leucine zipper that is required to hold together (dimerize) two DNA binding regions. The DNA binding region comprises a number of basic amino acids such as arginine and lysine. Proteins containing this domain are transcription factors.[1][2]

bZIP transcription factors

bZIP transcription factors are found in all eukaryotes and form one of the largest families of dimerizing TFs.[3][4] An evolutionary study from 2008 revealed that 4 bZIP genes were encoded by the genome of the most recent common ancestor of all plants.[5] Interactions between bZIP transcription factors are numerous and complex [6][7][3] and play important roles in cancer development[8] in epithelial tissues, steroid hormone synthesis by cells of endocrine tissues,[9] factors affecting reproductive functions,[10] and several other phenomena that affect human health.

bZIP domain containing proteins

  • AP-1 fos/jun heterodimer that forms a transcription factor
  • Jun-B transcription factor
  • CREB cAMP response element transcription factor
  • OPAQUE2 (O2) transcription factor of the 22-kD zein gene that encodes a class of storage proteins in the endosperm of maize (Zea Mays) kernels
  • NFE2L2 or Nrf2
  • Bzip Maf transcription factors

Human proteins containing this domain



  1. ^ Ellenberger T (1994). "Getting a grip in DNA recognition: structures of the basic region leucine zipper, and the basic region helix-loop-helix DNA-binding domains". Curr. Opin. Struct. Biol. 4 (1): 12–21. doi:10.1016/S0959-440X(94)90054-X.
  2. ^ Hurst HC (1995). "Transcription factors 1: bZIP proteins". Protein Profile. 2 (2): 101–68. PMID 7780801.
  3. ^ a b Amoutzias, G. D.; Veron, A. S.; Weiner, J.; Robinson-Rechavi, M.; Bornberg-Bauer, E.; Oliver, S. G.; Robertson, D. L. (2007-03-01). "One billion years of bZIP transcription factor evolution: conservation and change in dimerization and DNA-binding site specificity". Molecular Biology and Evolution. 24 (3): 827–835. doi:10.1093/molbev/msl211. ISSN 0737-4038. PMID 17194801.
  4. ^ Amoutzias, Grigoris D.; Robertson, David L.; Van de Peer, Yves; Oliver, Stephen G. (2008-05-01). "Choose your partners: dimerization in eukaryotic transcription factors". Trends in Biochemical Sciences. 33 (5): 220–229. doi:10.1016/j.tibs.2008.02.002. ISSN 0968-0004. PMID 18406148.
  5. ^ Corrêa LG, Riaño-Pachón DM, Schrago CG, dos Santos RV, Mueller-Roeber B, Vincentz M (2008). Shiu S (ed.). "The Role of bZIP Transcription Factors in Green Plant Evolution: Adaptive Features Emerging from Four Founder Genes". PLoS ONE. 3 (8): e2944. doi:10.1371/journal.pone.0002944. PMC 2492810. PMID 18698409.
  6. ^ Vinson, Charles; Acharya, Asha; Taparowsky, Elizabeth J. (2006-01-01). "Deciphering B-ZIP transcription factor interactions in vitro and in vivo" (PDF). Biochimica et Biophysica Acta. 1759 (1–2): 4–12. doi:10.1016/j.bbaexp.2005.12.005. ISSN 0006-3002. PMID 16580748.
  7. ^ Newman, John R. S.; Keating, Amy E. (2003-06-27). "Comprehensive identification of human bZIP interactions with coiled-coil arrays". Science. 300 (5628): 2097–2101. doi:10.1126/science.1084648. ISSN 1095-9203. PMID 12805554.
  8. ^ Vlahopoulos SA, Logotheti S, Mikas D, Giarika A, Gorgoulis V, Zoumpourlis V (April 2008). "The role of ATF-2 in oncogenesis". BioEssays. 30 (4): 314–27. doi:10.1002/bies.20734. PMID 18348191.
  9. ^ Manna PR, Dyson MT, Eubank DW, Clark BJ, Lalli E, Sassone-Corsi P, Zeleznik AJ, Stocco DM (January 2002). "Regulation of steroidogenesis and the steroidogenic acute regulatory protein by a member of the cAMP response-element binding protein family". Mol. Endocrinol. 16 (1): 184–99. doi:10.1210/me.16.1.184. PMID 11773448.
  10. ^ Hoare S, Copland JA, Wood TG, Jeng YJ, Izban MG, Soloff MS (May 1999). "Identification of a GABP alpha/beta binding site involved in the induction of oxytocin receptor gene expression in human breast cells, potentiation by c-Fos/c-Jun". Endocrinology. 140 (5): 2268–79. doi:10.1210/en.140.5.2268. PMID 10218980.

External links

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Basic region leucine zipper Provide feedback

No Pfam abstract.

Literature references

  1. Jakoby M, Weisshaar B, Droge-Laser W, Vicente-Carbajosa J, Tiedemann J, Kroj T, Parcy F; , Trends Plant Sci 2002;7:106-111.: bZIP transcription factors in Arabidopsis. PUBMED:11906833 EPMC:11906833

  2. Sinclair AJ; , J Gen Virol 2003;84:1941-1949.: bZIP proteins of human gammaherpesviruses. PUBMED:12867624 EPMC:12867624

  3. Hurst HC; , Protein Profile 1995;2:101-168.: Transcription factors 1: bZIP proteins. PUBMED:7780801 EPMC:7780801

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR004827

The basic-leucine zipper (bZIP) domain transcription factors [ PUBMED:7780801 ] of eukaryotic are proteins that contain a basic region mediating sequence-specific DNA-binding followed by a leucine zipper region required for dimerisation.

Several structure of bZIP have been solved. The basic region and the leucine zipper form a contiguous alpha helice where the four hydrophobic residues of the leucine zipper are oriented on one side. This conformation allows dimerization in parallel and it bends the helices so that the newly functional dimer forms a flexible fork where the basic domains, at the N-terminal open end, can then interact with DNA. The two leucine zipper are therefore oriented perpendicular to the DNA [ PUBMED:1473154 ].

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan bZIP (CL0018), which has the following description:

This family of eukaryotic transcription factors contain a basic region adjacent to a leucine zipper.

The clan contains the following 3 members:

bZIP_1 bZIP_2 bZIP_Maf


We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

Representative proteomes UniProt
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Representative proteomes UniProt

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We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: PfamB-200; Release 14.0;
Previous IDs: none
Type: Coiled-coil
Sequence Ontology: SO:0001080
Author: Studholme DJ
Number in seed: 41
Number in full: 10541
Average length of the domain: 53.70 aa
Average identity of full alignment: 31 %
Average coverage of the sequence by the domain: 17.07 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 22.3 22.3
Trusted cut-off 22.3 22.3
Noise cut-off 22.2 22.2
Model length: 54
Family (HMM) version: 18
Download: download the raw HMM for this family

Species distribution

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Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the bZIP_2 domain has been found. There are 413 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
A0A060D2L0 View 3D Structure Click here
A0A0P0V9D3 View 3D Structure Click here
A0A0P0XYV6 View 3D Structure Click here
A0A0R0GZ65 View 3D Structure Click here
A0A0R0H3W8 View 3D Structure Click here
A0A0R0HI81 View 3D Structure Click here
A0A0R0HS94 View 3D Structure Click here
A0A0R4IMA7 View 3D Structure Click here
A0A1D5NSP6 View 3D Structure Click here
A0A1D5NSQ7 View 3D Structure Click here
A0A1D6KKS3 View 3D Structure Click here
A0A1D8PDR2 View 3D Structure Click here
A0A1D8PIL5 View 3D Structure Click here
A0A1D8PQN4 View 3D Structure Click here
A0A2R8QII3 View 3D Structure Click here
A0A5F8MPM5 View 3D Structure Click here
A0A5F9ZHS7 View 3D Structure Click here
A1ZAC2 View 3D Structure Click here
A5PME1 View 3D Structure Click here
B3DJ19 View 3D Structure Click here
B4FT66 View 3D Structure Click here
B4G1L8 View 3D Structure Click here
B9G4L6 View 3D Structure Click here
C6TGZ0 View 3D Structure Click here
E9QHS1 View 3D Structure Click here
F1Q4X0 View 3D Structure Click here
F1Q964 View 3D Structure Click here
F1QEE6 View 3D Structure Click here
F1QIC1 View 3D Structure Click here
F1QKJ7 View 3D Structure Click here
F1QP65 View 3D Structure Click here
F1QZP2 View 3D Structure Click here
F4IN23 View 3D Structure Click here
F4K9L7 View 3D Structure Click here
G5EBE5 View 3D Structure Click here
G5EE07 View 3D Structure Click here
G5EGQ7 View 3D Structure Click here
H2L0N3 View 3D Structure Click here
I1KEU6 View 3D Structure Click here
I1LJ22 View 3D Structure Click here