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11  structures 284  species 0  interactions 2313  sequences 29  architectures

Family: AF-4 (PF05110)

Summary: AF-4 proto-oncoprotein N-terminal region

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This is the Wikipedia entry entitled "AF4/FMR2 family". More...

AF4/FMR2 family Edit Wikipedia article

Transcriptional factor AF4/FMR2

AF4/FMR2 (AFF) is a family of nuclear transcriptional activators that encourage RNA elongation.[1]

A Drosophila FMR2 orthologue has been identified. Cells homozygous for a defective mutant of the gene are abnormally small, so the researchers named the gene Lilliputian (Lilli; Q9VQI9). It contains an AT-hook domain. It represents a novel pair-rule gene that acts in cytoskeleton regulation, segmentation and morphogenesis in Drosophila [2]

Human genes include AFF1, AFF2, AFF3, and AFF4. Fusion genes involving AFF1 can produce a rogue activator leading to leukemia. Mutations in AFF2 is implicated in breast cancer. A trinucleotide repeat disorder [1]


  1. ^ a b Melko M, Douguet D, Bensaid M, Zongaro S, Verheggen C, Gecz J, Bardoni B (May 2011). "Functional characterization of the AFF (AF4/FMR2) family of RNA-binding proteins: insights into the molecular pathology of FRAXE intellectual disability". Human Molecular Genetics. 20 (10): 1873–85. doi:10.1093/hmg/ddr069. PMID 21330300.
  2. ^ Wittwer, F; van der Straten, A; Keleman, K; Dickson, BJ; Hafen, E (March 2001). "Lilliputian: an AF4/FMR2-related protein that controls cell identity and cell growth". Development (Cambridge, England). 128 (5): 791–800. PMID 11171403. which we renamed lilliputian (lilli) based on the small size of homozygous lilli mutant cells

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.

AF-4 proto-oncoprotein N-terminal region Provide feedback

This family consists of AF4 (Proto-oncogene AF4) and FMR2 (Fragile X E mental retardation syndrome) nuclear proteins. These proteins have been linked to human diseases such as acute lymphoblastic leukaemia and mental retardation [1]. The family also contains a Drosophila AF4 protein homologue Lilliputian which contains an AT-hook domain. Lilliputian represents a novel pair-rule gene that acts in cytoskeleton regulation, segmentation and morphogenesis in Drosophila [2].

Literature references

  1. Wittwer F, van der Straten A, Keleman K, Dickson BJ, Hafen E; , Development 2001;128:791-800.: Lilliputian: an AF4/FMR2-related protein that controls cell identity and cell growth. PUBMED:11171403 EPMC:11171403

  2. Tang AH, Neufeld TP, Rubin GM, Muller HA; , Development 2001;128:801-813.: Transcriptional regulation of cytoskeletal functions and segmentation by a novel maternal pair-rule gene, lilliputian. PUBMED:11171404 EPMC:11171404

This tab holds annotation information from the InterPro database.

No InterPro data for this Pfam family.

Domain organisation

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

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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.

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Curation and family details

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Seed source: Pfam-B_6407 (release 7.7)
Previous IDs: none
Type: Family
Sequence Ontology: SO:0100021
Author: Moxon SJ , Bateman A
Number in seed: 26
Number in full: 2313
Average length of the domain: 296.4 aa
Average identity of full alignment: 31 %
Average coverage of the sequence by the domain: 38.92 %

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 25.1 25.1
Trusted cut-off 25.1 25.1
Noise cut-off 25.0 25.0
Model length: 514
Family (HMM) version: 16
Download: download the raw HMM for this family

Species distribution

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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 AF-4 domain has been found. There are 11 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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