Open Access

The AP-2 family of transcription factors

  • Dawid Eckert1,
  • Sandra Buhl1,
  • Susanne Weber1,
  • Richard Jäger1 and
  • Hubert Schorle1Email author
Genome Biology20056:246

DOI: 10.1186/gb-2005-6-13-246

Published: 28 December 2005

Summary

The AP-2 family of transcription factors consists of five different proteins in humans and mice: AP-2α, AP-2β, AP-2γ, AP-2δ and AP-2ε. Frogs and fish have known orthologs of some but not all of these proteins, and homologs of the family are also found in protochordates, insects and nematodes. The proteins have a characteristic helix-span-helix motif at the carboxyl terminus, which, together with a central basic region, mediates dimerization and DNA binding. The amino terminus contains the transactivation domain. AP-2 proteins are first expressed in primitive ectoderm of invertebrates and vertebrates; in vertebrates, they are also expressed in the emerging neural-crest cells, and AP-2α -/- animals have impairments in neural-crest-derived facial structures. AP-2β is indispensable for kidney development and AP-2γ is necessary for the formation of trophectoderm cells shortly after implantation; AP-2α and AP-2γ levels are elevated in human mammary carcinoma and seminoma. The general functions of the family appear to be the cell-type-specific stimulation of proliferation and the suppression of terminal differentiation during embryonic development.

Gene organization and evolutionary history

The AP-2 family of transcription factors (Ensembl Family ENSF00000001105) consists in humans and mice of five members, AP-2α, AP-2β, AP-2γ, AP-2δ and AP-2ε; frogs and fish have some of these proteins, and homologs are also known in invertebrates. The chromosomal locations and accession numbers of the family are given in Tables 1 and 2, respectively. All mammalian AP-2 proteins except AP-2δ are encoded by seven exons and share a characteristic domain structure (reviewed in [1]; for AP-2δ see [2] and for AP-2ε see [3, 4]). Orthologs show a similarity between 60 and 99% at the amino-acid level, whereas paralogs show a similarity between 56 and 78%.
Table 1

Chromosomal locations of AP-2 genes from selected species

 

AP-2α

AP-2β

AP-2γ

AP-2δ

AP-2ε

Other AP-2 genes*

H. sapiens

6p24

6p12

20q13.2

6p12.1

1p34.3

 

P. troglodytes

6p22.3

6p12

21

-

-

 

M. musculus

13 A5-B1

1 A2-A4

2 H3-H4

1 A3

4 D2.2

 

R. norvegicus

17p12

9q13

3q42

9q13

5q36

 

G. gallus

2 3

-

3

-

  

X. tropicalis

scaffold_278

-

-

-

-

 

D. rerio

24

20

-

-

-

 

C. elegans

     

II

D. melanogaster

     

3L

*The AP-2 genes of C. elegans and D. melanogaster are not orthologous to any of the five mammalian genes. Data taken from the database entries for the accession numbers given in Table 2. No information on mapping is available for the C. intestinalis AP-2 gene.

Table 2

Accession numbers for AP-2 proteins from selected species

 

AP-2α

AP-2β

AP-2γ

AP-2δ

AP-2ε

Other AP-2 proteins*

H. sapiens

NP_003211

NP_003212

NP_003213

NP_758438

NP_848643

 

P. troglodytes

-

XP_518532

XP_526337

-

-

 

M. musculus

NP_035677

NP_033360

NP_033361

NP_694794

NP_945198

 

R. norvegicus

XP_225238

XP_217356

NP_958823

XP_236975

XP_233526

 

G. gallus

NP_990425

NP_990226

-

XP_426224

-

 

X. tropicalis

AAD53289

-

-

-

-

 

X. laevis

AAA49972

-

-

-

-

 

D. rerio

NP_789829

NP_001019836

-

-

-

 

C. elegans

     

NP_4951819

D. melanogaster

     

NP_730664

C. intestinalis

     

BAE06307 and BAE06308

*The AP-2 genes of C. elegans, D. melanogaster and C. intestinalis are not orthologous to any of the five mammalian genes.

Analysis of the phylogenetic tree (Figure 1) reveals that the vertebrate AP-2 proteins are grouped together and are divided into five groups. The single Xenopus AP-2 is most closely related to mammalian AP-2α proteins. As the genes AP-2β and AP-2δ are found on the same chromosome in chickens, rodents and humans (Table 1), it is likely that they are the result of an internal duplication. According to the phylogenetic tree, AP-2δ genes appear to have separated from the rest of the family early in the vertebrate clade and to have evolved separately (Figure 1). A BLAST search of the puffer fish Fugu rubripes fourth genome assembly database [5] suggests that there are orthologs of AP-2α, AP-2β, AP-2γ and AP-2ε but not AP-2δ genes in bony fish, although only orthologs of AP-2α and AP-2β have been found in zebrafish.
https://static-content.springer.com/image/art%3A10.1186%2Fgb-2005-6-13-246/MediaObjects/13059_2005_Article_990_Fig1_HTML.jpg
Figure 1

Phylogenetic tree of the AP-2 family. Amino-acid sequence alignments were performed using ClustalW implemented in Sequence Data Explorer of the MEGA3 software [67]. The phylogenetic tree was created using the neighbor-joining method (gaps setting: pairwise deletion; distance method: number of differences). Numbers at selected nodes indicate the percentage frequencies of branch association on the basis of 1,000 bootstrap repetitions. The scale bar indicates the number of residue changes. Asterisks indicate predicted proteins; brackets denote subfamilies in vertebrates. Species: Caenorhabditis elegans (nematode); Ciona intestinalis (sea squirt); Drosophila melanogaster (fruit fly); Danio rerio (zebrafish); Gallus gallus (chicken); Homo sapiens (human); Mus musculus (mouse); Pan troglodytes (chimpanzee); Rattus norvegicus (rat); Xenopus laevis and Xenopus tropicalis (frog).

In the genome of the protochordate Ciona intestinalis a single AP-2 gene has been predicted; the phylogenetic tree shows that the protein evolved before the split of the AP-2α, AP-2β, AP-2γ and AP-2ε proteins, with the highest sequence similarity with the AP-2α group, suggesting that AP-2α might be most similar to the ancestor of AP-2 proteins. This hypothesis is further supported by the conserved epithelial expression patterns of murine AP-2α[6], Xenopus AP-2 [7] and the amphioxus and lamprey AP-2[8] genes. As expected, the two Caenorhabditis elegans and the single Drosophila melanogaster AP-2 proteins show the weakest phylogenetic relationship with vertebrate and protochordate AP-2 transcription factors; they form an outgroup to the other AP-2 family members (Figure 1). Given that no AP-2 gene has been identified in yeast, the family probably originated late in evolution and expanded considerably in the vertebrates.

Characteristic structural features

All AP-2 proteins share a highly conserved helix-span-helix dimerization motif at the carboxyl terminus, followed by a central basic region and a less conserved domain rich in proline and glutamine at the amino terminus (Figure 2). The proteins are able to form hetero- as well as homodimers. The helix-span-helix motif together with the basic region mediates DNA binding [9, 10], and the proline- and glutamine-rich region is responsible for transactivation. AP-2 has been shown to bind to the palindromic consensus sequence 5'-GCCN3GGC-3', found in various cellular and viral enhancers (reviewed in [1]); a binding-site selection assay in vitro also revealed the additional binding motifs 5'-GCCN3GGC-3', 5'-GCCN4GGC-3' and 5'-GCCN3/4GGG-3' [11]. Other binding sites differing from these sequence motifs, for example, the SV40 enhancer element 5'-CCCCAGGC-3' [12], indicate that AP-2 proteins may bind to a range of G/C-rich elements with variable affinities. Target genes with AP-2-binding sites in their promoter sequences are involved in biological processes such as cell growth and differentiation and include, for example, those encoding insulin-like growth factor binding protein 5 (IGF-BP5) with the binding site 5'-GCCAGGGGC-3' [13], prothymosin-α (5'-GCCGGTGGGC-3') [14] and the estrogen receptor (5'-GCCTGCGGGG-3') [15].
https://static-content.springer.com/image/art%3A10.1186%2Fgb-2005-6-13-246/MediaObjects/13059_2005_Article_990_Fig2_HTML.jpg
Figure 2

A schematic representation of the protein structure of an AP-2α dimer, showing the proline- and glutamine (P/Q)-rich transactivation domain (89 amino acids, red), the PY motif within this domain (5 amino acids, green), the basic domain (20 amino acids, yellow) and the helix-span-helix motif (131 amino acids, blue). The helix-span-helix motif is responsible for dimerization of the proteins and mediates DNA binding together with the basic domain. Modified from SwissProt, ID: P34056 [68].

Most AP-2 proteins have a PY motif (XPPXY) and other highly conserved critical residues in the transactivation domain; by contrast, the PY motif is missing in AP-2δ but the amino- and carboxy-terminal ends of the core sequence of the transactivation domain are still conserved. In addition, the binding affinity of AP-2δ to conserved AP-2-binding sites is much lower than that of other AP-2 proteins [2]. This suggests that AP-2δ might transactivate genes in vivo by a different mechanism from that used by other AP-2 proteins, probably through interactions with a novel group of coactivators and through a different affinity for AP-2-binding sites. Alternatively, AP-2δ might act as a negative regulator, inhibiting or modulating the transactivation capability or DNA-binding affinity of the other AP-2 family members. The crystal structure of the AP-2 proteins has not yet been solved.

Localization and function

AP-2 transcription factors are localized predominantly in the nucleus, where they bind to target sequences and regulate transcription of target genes. AP-2 proteins have also been shown to interfere with other signal transduction pathways; for example, it has been proposed that they modulate the pathway downstream of the developmental signaling molecule Wnt by associating with the Adenomatous polyposis coli (APC) tumor suppressor protein in the nucleus [16].

The activity of AP-2 proteins can be controlled at multiple levels: their transactivation potential, their DNA binding, their subcellular localization [1719] and their degradation [20, 21] can all be modified. Mechanisms of regulation include post-translational modifications, such as protein kinase A-mediated phosphorylation [22, 23], sumoylation [24] and redox regulation [25, 26], as well as physical interaction with various proteins (see Table 3 for a comprehensive list). Interacting proteins either modulate the activity of AP-2 proteins or are influenced in their function by binding to AP-2 proteins.
Table 3

Proteins that physically interact with AP-2 transcription factors

Protein

Description

Domain of AP-2 proteins that interacts*

Function of interaction

Reference

APC

Adenomatous polyposis coli tumor suppressor

Basic region

Inhibition of β-catenin/TCF/LEF-dependent transcription

[16]

CITED2

Coactivator

DD

Transcriptional activation

[69]

CITED4

Coactivator

n.d.

Transcriptional activation

[70]

CDP

CCAAT displacement protein

DBD, DD

Repression of the hamster histone H3.2 promoter

[71]

DEK

Oncoprotein, chromatin remodeling

n.d.

Transcriptional activation

[72]

E1A

Transforming protein of adenovirus

DBD, DD

Repression of AP-2 target genes

[73]

c-Myc

Oncoprotein

Carboxyl terminus

Impairment of Myc/Max DNA-binding and transactivation

[14]

PARP

PolyADP-ribose polymerase

Carboxyl terminus

Transcriptional activation

[74]

PAX-6

Transcription factor

n.d.

Stimulation of gelatinase B activation

[75]

PC4

Coactivator

 

Transcriptional activation

[24]

P300/CBP

Coactivator

Amino terminus

Transcriptional activation

[69]

p53

Tumor suppressor

n.d.

Augmentation of p53-dependent transcription

[76]

RAP74

Subunit of transcription factor TFIIF

Central region containing DBD

Unknown

[74]

Rb

Retinoblastoma tumor suppressor

Amino terminus

Repression of the hamster histone H3.2 promoter; transcriptional activation of the E-cadherin gene

[77,78]

SP1

Transcription factor

Basic region

Transcriptional activation of the ovine CYP11A1 gene

[79]

SV40T

Transforming protein of SV40 virus

n.d.

Blocks DNA binding of AP-2 protein

[12]

UBC9

E2-conjugating enzyme

DBD, DD

Sumoylation

[80]

WWOX

Tumor suppressor

Amino terminus PY motif

Cytoplasmic localization PPPY motif

[17]

YB-1

Transcription factor

n.d.

Stimulation of gelatinase A transcription

[81]

YY1

Transcription factor

DBD, DD

Stimulation of the hamster histone H3.2 promoter

[82]

*Abbreviations: DBD, DNA-binding domain; DD, dimerization domain; n.d., not determined. It is currently not entirely clear whether Rb binds AP-2 only via the amino terminus [78], or whether the DNA-binding domain is also necessary [77].

The tissue distribution and developmental functions of AP-2 transcription factors have been studied extensively in several species. Drosophila AP-2 (dAP-2) is expressed in the maxillary segment and neural structures during embryogenesis, and in the central nervous system (CNS) and the leg, antennal and labial imaginal disks during larval development [27, 28]. Mutation of the dAP-2 gene leads to defects in proboscis development and leg-joint formation [29, 30].

The multiple overlapping and diverging expression patterns of AP-2 family proteins suggest that, following the expansion of the family during vertebrate evolution, redundant and non-redundant functions of the individual AP-2 family members evolved. Although the single AP-2 protein in the cephalochordate amphioxus is expressed mainly in non-neuronal ectoderm, in the lamprey, a primitive vertebrate, AP-2 has co-opted a second expression domain, the neural crest [8]. The single AP-2 homolog described so far in Xenopus is expressed in the epidermis and neural crest and has been shown to be critical for the development of these structures [7, 3133]. In zebrafish, the two AP-2 family members, tfap2a and tfap2b [34], are coexpressed in the neural tube, the ectoderm and the pronephric ducts of the developing kidney, but only tfap2a is expressed in neural crest cells [35, 36]. Positional cloning revealed that the zebrafish point mutants named mont blanc [35] and lockjaw [36] encode tfap2a; the mutant animals display impaired development of neural-crest derivatives, such as the facial skeleton, the peripheral nervous system and pigment cells [37, 38]. It is also interesting to note that AP-2 proteins are expressed in the primitive ectoderm of both invertebrates and vertebrates, suggesting an evolutionarily conserved role for the family in the formation of this tissue.

In mice, three of the five AP-2 family members (AP-2α, AP-2β and AP-2γ) are coexpressed in neural-crest cells, the peripheral nervous system, facial and limb mesenchyme, various epithelia of the developing embryo and the extraembryonic trophectoderm [2, 3941]. AP-2δ expression is restricted mainly to the developing heart, CNS and retina [39], whereas AP-2ε expression is detected in cells of the olfactory bulb [3, 4]. Despite the overlapping expression patterns of AP-2α, AP-2β and AP-2γ, disruption of these AP-2 genes reveals non-redundant roles during development. Mutation of AP-2α predominantly affects the cranial neural crest and the limb mesenchyme, leading to disturbances of facial and limb development in a manner reminiscent of the defects described in dAP2 mutant flies [42, 43]. AP-2β and AP-2γ, on the other hand, are essential for kidney development [44, 45] or placentation of the embryo [46, 47], respectively. In humans, mutations generating a dominant negative allele of AP-2β have been shown to be the cause of Char syndrome (Online Mendelian Inheritance in Man (OMIM) ID 169100 [48]); the hallmarks of this syndrome are patent ductus arteriosus (abnormal persistence of a normal fetal heart structure after birth) with facial dysmorphism and abnormal fifth digits [49, 50].

Comparing all mutant phenotypes, it can be seen that loss of AP-2 transcription factor activity generally impairs proliferation and induces premature differentiation and/or apoptosis in various cell types during development. This conclusion is further substantiated by results from a screen for AP-2α target genes [51] and supported by gain-of-function studies in Xenopus and mice [31, 52, 53]. As uncontrolled proliferation leads to malignancies, AP-2 transcription factors are not only implicated in normal development, but also seem to be involved in cellular neoplasia, and enhanced AP-2 levels have been reported in various types of cancer [19, 5460]. In a murine breast-cancer model, tumor progression is enhanced after transgenic overexpression of AP-2γ [55]. Thus, AP-2 proteins can be viewed as gatekeepers controlling the balance between proliferation and differentiation during embryogenesis.

Frontiers

The lethal phenotypes of the AP-2 mutants generated so far have precluded an analysis of the roles of AP-2 transcription factors in adult tissues. We and others are currently exploiting the power of conditional mouse mutants to overcome these restrictions [6163]. Such approaches will not only shed light on normal AP-2 functions but will probably also lead to unique insights into human disorders.

Complementary approaches currently include the identification of AP-2 target genes; this might give a better understanding of developmental disturbances and pave the way to novel treatment options [51, 64]. At the molecular level, one major challenge will be the identification of specific AP-2 homo- or hetero-dimeric complexes bound to a particular promoter and the identification of the specific properties of each complex with respect to gene regulation. Also, the signaling pathways responsible for induction of AP-2 genes are currently under investigation. A cross-species comparison of the various AP-2 promoters may give insights into the evolution of tissue specificity and help to determine important enhancer elements. Moreover, given that CpG islands are present in AP-2 promoters, epigenetic regulation such as DNA methylation also needs to be considered.

AP-2 transcription factors are currently being studied extensively in human cancer, and they may be of diagnostic value, as has been demonstrated for mammary or testicular carcinoma [19, 54, 56, 65, 66]. It is tempting to speculate that AP-2 transcription factors might not only be molecular markers for certain types of cancer, but could also be causally involved in their etiologies and would therefore represent a potential target for therapeutic intervention.

Declarations

Acknowledgements

We thank Roland Dosch and Michael Pankratz for critical reading of the manuscript. This work was supported by funding from the Deutsche Forschungsgemeinschaft (# 503/6 and 503/7) that was awarded to H.S.

Authors’ Affiliations

(1)
Department of Developmental Pathology, Institute of Pathology

References

  1. Hilger-Eversheim K, Moser M, Schorle H, Buettner R: Regulatory roles of AP-2 transcription factors in vertebrate development, apoptosis and cell-cycle control. Gene. 2000, 260: 1-12. 10.1016/S0378-1119(00)00454-6.PubMedView Article
  2. Zhao F, Satoda M, Licht JD, Hayashizaki Y, Gelb BD: Cloning and characterization of a novel mouse AP-2 transcription factor, AP-2delta, with unique DNA binding and transactivation properties. J Biol Chem. 2001, 276: 40755-40760. 10.1074/jbc.M106284200.PubMedView Article
  3. Wang HV, Vaupel K, Buettner R, Bosserhoff AK, Moser M: Identification and embryonic expression of a new AP-2 transcription factor, AP-2 epsilon. Dev Dyn. 2004, 231: 128-135. 10.1002/dvdy.20119.PubMedView Article
  4. Feng W, Williams T: Cloning and characterization of the mouse AP-2 epsilon gene: a novel family member expressed in the developing olfactory bulb. Mol Cell Neurosci. 2003, 24: 460-475. 10.1016/S1044-7431(03)00209-4.PubMedView Article
  5. IMCB - Fugu Genome Project. [http://​www.​fugu-sg.​org/​]
  6. Mitchell PJ, Timmons PM, Hebert JM, Rigby PW, Tjian R: Transcription factor AP-2 is expressed in neural crest cell lineages during mouse embryogenesis. Genes Dev. 1991, 5: 105-119.PubMedView Article
  7. Snape AM, Winning RS, Sargent TD: Transcription factor AP-2 is tissue-specific in Xenopus and is closely related or identical to keratin transcription factor 1 (KTF-1). Development. 1991, 113: 283-293.PubMed
  8. Meulemans D, Bronner-Fraser M: Amphioxus and lamprey AP-2 genes: implications for neural crest evolution and migration patterns. Development. 2002, 129: 4953-4962.PubMed
  9. Williams T, Tjian R: Analysis of the DNA-binding and activation properties of the human transcription factor AP-2. Genes Dev. 1991, 5: 670-682.PubMedView Article
  10. Williams T, Tjian R: Characterization of a dimerization motif in AP-2 and its function in heterologous DNA-binding proteins. Science. 1991, 251: 1067-1071.PubMedView Article
  11. Mohibullah N, Donner A, Ippolito JA, Williams T: SELEX and missing phosphate contact analyses reveal flexibility within the AP-2[alpha] protein: DNA binding complex. Nucleic Acids Res. 1999, 27: 2760-2769. 10.1093/nar/27.13.2760.PubMedPubMed CentralView Article
  12. Mitchell PJ, Wang C, Tjian R: Positive and negative regulation of transcription in vitro: enhancer-binding protein AP-2 is inhibited by SV40 T antigen. Cell. 1987, 50: 847-861. 10.1016/0092-8674(87)90512-5.PubMedView Article
  13. Duan C, Clemmons DR: Transcription factor AP-2 regulates human insulin-like growth factor binding protein-5 gene expression. J Biol Chem. 1995, 270: 24844-24851. 10.1074/jbc.270.42.24844.PubMedView Article
  14. Gaubatz S, Imhof A, Dosch R, Werner O, Mitchell P, Buettner R, Eilers M: Transcriptional activation by Myc is under negative control by the transcription factor AP-2. EMBO J. 1995, 14: 1508-1519.PubMedPubMed Central
  15. Newman SP, Bates NP, Vernimmen D, Parker MG, Hurst HC: Cofactor competition between the ligand-bound oestrogen receptor and an intron 1 enhancer leads to oestrogen repression of ERBB2 expression in breast cancer. Oncogene. 2000, 19: 490-497. 10.1038/sj.onc.1203416.PubMedView Article
  16. Li Q, Dashwood RH: Activator protein 2alpha associates with adenomatous polyposis coli/beta-catenin and inhibits beta-catenin/T-cell factor transcriptional activity in colorectal cancer cells. J Biol Chem. 2004, 279: 45669-45675. 10.1074/jbc.M405025200.PubMedPubMed CentralView Article
  17. Aqeilan RI, Palamarchuk A, Weigel RJ, Herrero JJ, Pekarsky Y, Croce CM: Physical and functional interactions between the Wwox tumor suppressor protein and the AP-2gamma transcription factor. Cancer Res. 2004, 64: 8256-8261. 10.1158/0008-5472.CAN-04-2055.PubMedView Article
  18. Mazina OM, Phillips MA, Williams T, Vines CA, Cherr GN, Rice RH: Redistribution of transcription factor AP-2alpha in differentiating cultured human epidermal cells. J Invest Dermatol. 2001, 117: 864-870. 10.1046/j.0022-202x.2001.01472.x.PubMedView Article
  19. Pellikainen J, Naukkarinen A, Ropponen K, Rummukainen J, Kataja V, Kellokoski J, Eskelinen M, Kosma VM: Expression of HER2 and its association with AP-2 in breast cancer. Eur J Cancer. 2004, 40: 1485-1495. 10.1016/j.ejca.2004.02.020.PubMedView Article
  20. Li M, Wang Y, Hung MC, Kannan P: Inefficient proteasomal-degradation pathway stabilizes AP-2alpha and activates HER-2/neu gene in breast cancer. Int J Cancer. 2005, doi:10.1002/ijc.21426.
  21. Nyormoi O, Wang Z, Doan D, Ruiz M, McConkey D, Bar-Eli M: Transcription factor AP-2alpha is preferentially cleaved by caspase 6 and degraded by proteasome during tumor necrosis factor alpha-induced apoptosis in breast cancer cells. Mol Cell Biol. 2001, 21: 4856-4867. 10.1128/MCB.21.15.4856-4867.2001.PubMedPubMed CentralView Article
  22. Garcia MA, Campillos M, Marina A, Valdivieso F, Vazquez J: Transcription factor AP-2 activity is modulated by protein kinase A-mediated phosphorylation. FEBS Lett. 1999, 444: 27-31. 10.1016/S0014-5793(99)00021-6.PubMedView Article
  23. Park K, Kim KH: The site of cAMP action in the insulin induction of gene expression of acetyl-CoA carboxylase is AP-2. J Biol Chem. 1993, 268: 17811-17819.PubMed
  24. Zhong L, Wang Y, Kannan P, Tainsky MA: Functional characterization of the interacting domains of the positive coactivator PC4 with the transcription factor AP-2alpha. Gene. 2003, 320: 155-164. 10.1016/S0378-1119(03)00823-0.PubMedView Article
  25. Grether-Beck S, Felsner I, Brenden H, Krutmann J: Mitochondrial cytochrome c release mediates ceramide-induced activator protein 2 activation and gene expression in keratinocytes. J Biol Chem. 2003, 278: 47498-47507. 10.1074/jbc.M309511200.PubMedView Article
  26. Huang Y, Domann FE: Redox modulation of AP-2 DNA binding activity in vitro. Biochem Biophys Res Commun. 1998, 249: 307-312. 10.1006/bbrc.1998.9139.PubMedView Article
  27. Bauer R, McGuffin ME, Mattox W, Tainsky MA: Cloning and characterization of the Drosophila homologue of the AP-2 transcription factor. Oncogene. 1998, 17: 1911-1922. 10.1038/sj.onc.1202114.PubMedView Article
  28. Monge I, Mitchell PJ: DAP-2, the Drosophila homolog of transcription factor AP-2. Mech Dev. 1998, 76: 191-195. 10.1016/S0925-4773(98)00125-7.PubMedView Article
  29. Kerber B, Monge I, Mueller M, Mitchell PJ, Cohen SM: The AP-2 transcription factor is required for joint formation and cell survival in Drosophila leg development. Development. 2001, 128: 1231-1238.PubMed
  30. Monge I, Krishnamurthy R, Sims D, Hirth F, Spengler M, Kammermeier L, Reichert H, Mitchell PJ: Drosophila transcription factor AP-2 in proboscis, leg and brain central complex development. Development. 2001, 128: 1239-1252.PubMed
  31. Luo T, Matsuo-Takasaki M, Thomas ML, Weeks DL, Sargent TD: Transcription factor AP-2 is an essential and direct regulator of epidermal development in Xenopus. Dev Biol. 2002, 245: 136-144. 10.1006/dbio.2002.0621.PubMedView Article
  32. Winning RS, Shea LJ, Marcus SJ, Sargent TD: Developmental regulation of transcription factor AP-2 during Xenopus laevis embryogenesis. Nucleic Acids Res. 1991, 19: 3709-3714.PubMedPubMed CentralView Article
  33. Luo T, Lee YH, Saint-Jeannet JP, Sargent TD: Induction of neural crest in Xenopus by transcription factor AP2alpha. Proc Natl Acad Sci USA. 2003, 100: 532-537. 10.1073/pnas.0237226100.PubMedPubMed CentralView Article
  34. Knight RD, Javidan Y, Zhang T, Nelson S, Schilling TF: AP2-dependent signals from the ectoderm regulate craniofacial development in the zebrafish embryo. Development. 2005, 132: 3127-3138. 10.1242/dev.01879.PubMedView Article
  35. Holzschuh J, Barrallo-Gimeno A, Ettl AK, Durr K, Knapik EW, Driever W: Noradrenergic neurons in the zebrafish hindbrain are induced by retinoic acid and require tfap2a for expression of the neurotransmitter phenotype. Development. 2003, 130: 5741-5754. 10.1242/dev.00816.PubMedView Article
  36. Knight RD, Nair S, Nelson SS, Afshar A, Javidan Y, Geisler R, Rauch GJ, Schilling TF: lockjaw encodes a zebrafish tfap2a required for early neural crest development. Development. 2003, 130: 5755-5768. 10.1242/dev.00575.PubMedView Article
  37. Barrallo-Gimeno A, Holzschuh J, Driever W, Knapik EW: Neural crest survival and differentiation in zebrafish depends on mont blanc/tfap2a gene function. Development. 2004, 131: 1463-1477. 10.1242/dev.01033.PubMedView Article
  38. Knight RD, Javidan Y, Nelson S, Zhang T, Schilling T: Skeletal and pigment cell defects in the lockjaw mutant reveal multiple roles for zebrafish tfap2a in neural crest development. Dev Dyn. 2004, 229: 87-98. 10.1002/dvdy.10494.PubMedView Article
  39. Zhao F, Lufkin T, Gelb BD: Expression of Tfap2d, the gene encoding the transcription factor Ap-2 delta, during mouse embryogenesis. Gene Expr Patterns. 2003, 3: 213-217. 10.1016/S1567-133X(02)00067-4.PubMedView Article
  40. Moser M, Ruschoff J, Buettner R: Comparative analysis of AP-2 alpha and AP-2 beta gene expression during murine embryogenesis. Dev Dyn. 1997, 208: 115-124. 10.1002/(SICI)1097-0177(199701)208:1<115::AID-AJA11>3.0.CO;2-5.PubMedView Article
  41. Chazaud C, Oulad-Abdelghani M, Bouillet P, Decimo D, Chambon P, Dolle P: AP-2.2, a novel gene related to AP-2, is expressed in the forebrain, limbs and face during mouse embryogenesis. Mech Dev. 1996, 54: 83-94. 10.1016/0925-4773(95)00463-7.PubMedView Article
  42. Schorle H, Meier P, Buchert M, Jaenisch R, Mitchell PJ: Transcription factor AP-2 essential for cranial closure and craniofacial development. Nature. 1996, 381: 235-238. 10.1038/381235a0.PubMedView Article
  43. Zhang J, Hagopian-Donaldson S, Serbedzija G, Elsemore J, Plehn-Dujowich D, McMahon AP, Flavell RA, Williams T: Neural tube, skeletal and body wall defects in mice lacking transcription factor AP-2. Nature. 1996, 381: 238-241. 10.1038/381238a0.PubMedView Article
  44. Moser M, Dahmen S, Kluge R, Grone H, Dahmen J, Kunz D, Schorle H, Buettner R: Terminal renal failure in mice lacking transcription factor AP-2 beta. Lab Invest. 2003, 83: 571-578.PubMedView Article
  45. Moser M, Pscherer A, Roth C, Becker J, Mucher G, Zerres K, Dixkens C, Weis J, Guay-Woodford L, Buettner R, et al: Enhanced apoptotic cell death of renal epithelial cells in mice lacking transcription factor AP-2beta. Genes Dev. 1997, 11: 1938-1948.PubMedPubMed CentralView Article
  46. Auman HJ, Nottoli T, Lakiza O, Winger Q, Donaldson S, Williams T: Transcription factor AP-2gamma is essential in the extraembryonic lineages for early postimplantation development. Development. 2002, 129: 2733-2747.PubMed
  47. Werling U, Schorle H: Transcription factor gene AP-2 gamma essential for early murine development. Mol Cell Biol. 2002, 22: 3149-3156. 10.1128/MCB.22.9.3149-3156.2002.PubMedPubMed CentralView Article
  48. OMIM - Online Mendelian Inheritance in Man. [http://​www.​ncbi.​nlm.​nih.​gov/​entrez/​query.​fcgi?​db=​OMIM]
  49. Zhao F, Weismann CG, Satoda M, Pierpont ME, Sweeney E, Thompson EM, Gelb BD: Novel TFAP2B mutations that cause Char syndrome provide a genotype-phenotype correlation. Am J Hum Genet. 2001, 69: 695-703. 10.1086/323410.PubMedPubMed CentralView Article
  50. Satoda M, Zhao F, Diaz GA, Burn J, Goodship J, Davidson HR, Pierpont ME, Gelb BD: Mutations in TFAP2B cause Char syndrome, a familial form of patent ductus arteriosus. Nat Genet. 2000, 25: 42-46. 10.1038/75578.PubMedView Article
  51. Pfisterer P, Ehlermann J, Hegen M, Schorle H: A subtractive gene expression screen suggests a role of transcription factor AP-2 alpha in control of proliferation and differentiation. J Biol Chem. 2002, 277: 6637-6644. 10.1074/jbc.M108578200.PubMedView Article
  52. Zhang J, Brewer S, Huang J, Williams T: Overexpression of transcription factor AP-2alpha suppresses mammary gland growth and morphogenesis. Dev Biol. 2003, 256: 127-145. 10.1016/S0012-1606(02)00119-7.PubMedView Article
  53. Jager R, Werling U, Rimpf S, Jacob A, Schorle H: Transcription factor AP-2gamma stimulates proliferation and apoptosis and impairs differentiation in a transgenic model. Mol Cancer Res. 2003, 1: 921-929.PubMed
  54. Pauls K, Jager R, Weber S, Wardelmann E, Koch A, Buttner R, Schorle H: Transcription factor AP-2gamma, a novel marker of gonocytes and seminomatous germ cell tumors. Int J Cancer. 2005, 115: 470-477. 10.1002/ijc.20913.PubMedView Article
  55. Jager R, Friedrichs N, Heim I, Buttner R, Schorle H: Dual role of AP-2gamma in ErbB-2-induced mammary tumorigenesis. Breast Cancer Res Treat. 2005, 90: 273-280. 10.1007/s10549-004-4815-x.PubMedView Article
  56. Hoei-Hansen CE, Nielsen JE, Almstrup K, Sonne SB, Graem N, Skakkebaek NE, Leffers H, Meyts ER: Transcription factor AP-2gamma is a developmentally regulated marker of testicular carcinoma in situ and germ cell tumors. Clin Cancer Res. 2004, 10: 8521-8530. 10.1158/1078-0432.CCR-04-1285.PubMedView Article
  57. Hurst HC: Update on HER-2 as a target for cancer therapy: the ERBB2 promoter and its exploitation for cancer treatment. Breast Cancer Res. 2001, 3: 395-398. 10.1186/bcr329.PubMedPubMed CentralView Article
  58. Beger M, Butz K, Denk C, Williams T, Hurst HC, Hoppe-Seyler F: Expression pattern of AP-2 transcription factors in cervical cancer cells and analysis of their influence on human papillomavirus oncogene transcription. J Mol Med. 2001, 79: 314-320. 10.1007/s001090100211.PubMedView Article
  59. Turner BC, Zhang J, Gumbs AA, Maher MG, Kaplan L, Carter D, Glazer PM, Hurst HC, Haffty BG, Williams T: Expression of AP-2 transcription factors in human breast cancer correlates with the regulation of multiple growth factor signalling pathways. Cancer Res. 1998, 58: 5466-5472.PubMed
  60. Bosher JM, Totty NF, Hsuan JJ, Williams T, Hurst HC: A family of AP-2 proteins regulates c-erbB-2 expression in mammary carcinoma. Oncogene. 1996, 13: 1701-1707.PubMed
  61. Nelson DK, Williams T: Frontonasal process-specific disruption of AP-2alpha results in postnatal midfacial hypoplasia, vascular anomalies, and nasal cavity defects. Dev Biol. 2004, 267: 72-92. 10.1016/j.ydbio.2003.10.033.PubMedView Article
  62. Brewer S, Feng W, Huang J, Sullivan S, Williams T: Wnt1-Cre-mediated deletion of AP-2alpha causes multiple neural crest-related defects. Dev Biol. 2004, 267: 135-152. 10.1016/j.ydbio.2003.10.039.PubMedView Article
  63. Werling U, Schorle H: Conditional inactivation of transcription factor AP-2gamma by using the Cre/loxP recombination system. Genesis. 2002, 32: 127-129. 10.1002/gene.10057.PubMedView Article
  64. Luo T, Zhang Y, Khadka D, Rangarajan J, Cho KW, Sargent TD: Regulatory targets for transcription factor AP2 in Xenopus embryos. Dev Growth Differ. 2005, 47: 403-413. 10.1111/j.1440-169X.2005.00809.x.PubMedView Article
  65. Friedrichs N, Jager R, Paggen E, Rudlowski C, Merkelbach-Bruse S, Schorle H, Buettner R: Distinct spatial expression patterns of AP-2alpha and AP-2gamma in non-neoplastic human breast and breast cancer. Mod Pathol. 2005, 18: 431-438. 10.1038/modpathol.3800292.PubMedView Article
  66. Hoei-Hansen CE, Nielsen JE, Almstrup K, Hansen MA, Skakkebaek NE, Rajpert-DeMeyts E, Leffers H: Identification of genes differentially expressed in testes containing carcinoma in situ. Mol Hum Reprod. 2004, 10: 423-431. 10.1093/molehr/gah059.PubMedView Article
  67. Kumar S, Tamura K, Nei M: MEGA3: Integrated software for Molecular Evolutionary Genetics Analysis and sequence alignment. Brief Bioinform. 2004, 5: 150-163. 10.1186/1471-2105-5-150.PubMedView Article
  68. Swiss-Prot. [http://​us.​expasy.​org/​sprot/​]
  69. Braganca J, Eloranta JJ, Bamforth SD, Ibbitt JC, Hurst HC, Bhattacharya S: Physical and functional interactions among AP-2 transcription factors, p300/CREB-binding protein, and CITED2. J Biol Chem. 2003, 278: 16021-16029. 10.1074/jbc.M208144200.PubMedView Article
  70. Braganca J, Swingler T, Marques FI, Jones T, Eloranta JJ, Hurst HC, Shioda T, Bhattacharya S: Human CREB-binding protein/p300-interacting transactivator with ED-rich tail (CITED) 4, a new member of the CITED family, functions as a co-activator for transcription factor AP-2. J Biol Chem. 2002, 277: 8559-8565. 10.1074/jbc.M110850200.PubMedView Article
  71. Wu F, Lee AS: CDP and AP-2 mediated repression mechanism of the replication-dependent hamster histone H3.2 promoter. J Cell Biochem. 2002, 84: 699-707. 10.1002/jcb.10094.PubMedView Article
  72. Campillos M, Garcia MA, Valdivieso F, Vazquez J: Transcriptional activation by AP-2alpha is modulated by the oncogene DEK. Nucleic Acids Res. 2003, 31: 1571-1575. 10.1093/nar/gkg247.PubMedPubMed CentralView Article
  73. Somasundaram K, Jayaraman G, Williams T, Moran E, Frisch S, Thimmapaya B: Repression of a matrix metalloprotease gene by E1A correlates with its ability to bind to cell type-specific transcription factor AP-2. Proc Natl Acad Sci USA. 1996, 93: 3088-3093. 10.1073/pnas.93.7.3088.PubMedPubMed CentralView Article
  74. Kannan P, Yu Y, Wankhade S, Tainsky MA: PolyADP-ribose polymerase is a coactivator for AP-2-mediated transcriptional activation. Nucleic Acids Res. 1999, 27: 866-874. 10.1093/nar/27.3.866.PubMedPubMed CentralView Article
  75. Sivak JM, West-Mays JA, Yee A, Williams T, Fini ME: Transcription factors Pax6 and AP-2alpha interact to coordinate corneal epithelial repair by controlling expression of matrix metalloproteinase gelatinase B. Mol Cell Biol. 2004, 24: 245-257. 10.1128/MCB.24.1.245-257.2004.PubMedPubMed CentralView Article
  76. McPherson LA, Loktev AV, Weigel RJ: Tumor suppressor activity of AP2alpha mediated through a direct interaction with p53. J Biol Chem. 2002, 277: 45028-45033. 10.1074/jbc.M208924200.PubMedView Article
  77. Wu F, Lee AS: Identification of AP-2 as an interactive target of Rb and a regulator of the G1/S control element of the hamster histone H3.2 promoter. Nucleic Acids Res. 1998, 26: 4837-4845. 10.1093/nar/26.21.4837.PubMedPubMed CentralView Article
  78. Batsche E, Muchardt C, Behrens J, Hurst HC, Cremisi C: RB and c-Myc activate expression of the E-cadherin gene in epithelial cells through interaction with transcription factor AP-2. Mol Cell Biol. 1998, 18: 3647-3658.PubMedPubMed CentralView Article
  79. Pena P, Reutens AT, Albanese C, D'Amico M, Watanabe G, Donner A, Shu IW, Williams T, Pestell RG: Activator protein-2 mediates transcriptional activation of the CYP11A1 gene by interaction with Sp1 rather than binding to DNA. Mol Endocrinol. 1999, 13: 1402-1416. 10.1210/me.13.8.1402.PubMedView Article
  80. Eloranta JJ, Hurst HC: Transcription factor AP-2 interacts with the SUMO-conjugating enzyme UBC9 and is sumolated in vivo. J Biol Chem. 2002, 277: 30798-30804. 10.1074/jbc.M202780200.PubMedView Article
  81. Mertens PR, Alfonso-Jaume MA, Steinmann K, Lovett DH: A synergistic interaction of transcription factors AP2 and YB-1 regulates gelatinase A enhancer-dependent transcription. J Biol Chem. 1998, 273: 32957-32965. 10.1074/jbc.273.49.32957.PubMedView Article
  82. Wu F, Lee AS: YY1 as a regulator of replication-dependent hamster histone H3.2 promoter and an interactive partner of AP-2. J Biol Chem. 2001, 276: 28-34. 10.1074/jbc.M006074200.PubMedView Article

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