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Protein Domain : IPR000315

Name  Zinc finger, B-box Short Name  Znf_B-box
Type  Domain Description  Zinc finger (Znf) domains are relatively small protein motifs which contain multiple finger-like protrusions that make tandem contacts with their target molecule. Some of these domains bind zinc, but many do not; instead binding other metals such as iron, or no metal at all. For example, some family members form salt bridges to stabilise the finger-like folds. They were first identified as a DNA-binding motif in transcription factor TFIIIA from Xenopus laevis(African clawed frog), however they are now recognised to bind DNA, RNA, protein and/or lipid substrates [, , , , ]. Their binding properties depend on the amino acid sequence of the finger domains and of the linker between fingers, as well as on the higher-order structures and the number of fingers. Znf domains are often found in clusters, where fingers can have different binding specificities. There are many superfamilies of Znf motifs, varying in both sequence and structure. They display considerable versatility in binding modes, even between members of the same class (e.g. some bind DNA, others protein), suggesting that Znf motifs are stable scaffolds that have evolved specialised functions. For example, Znf-containing proteins function in gene transcription, translation, mRNA trafficking, cytoskeleton organisation, epithelial development, cell adhesion, protein folding, chromatin remodelling and zinc sensing, to name but a few []. Zinc-binding motifs are stable structures, and they rarely undergo conformational changes upon binding their target. This entry represents B-box-type zinc finger domains, which are around 40 residues in length. B-box zinc fingers can be divided into two groups, where types 1 and 2 B-box domains differ in their consensus sequence and in the spacing of the 7-8 zinc-binding residues. Several proteins contain both types 1 and 2 B-boxes, suggesting some level of cooperativity between these two domains. B-box domains are found in over 1500 proteins from a variety of organisms. They are found in TRIM (tripartite motif) proteins that consist of an N-terminal RING finger (originally called an A-box), followed by 1-2 B-box domains and a coiled-coil domain (also called RBCC for Ring, B-box, Coiled-Coil). TRIM proteins contain a type 2 B-box domain, and may also contain a type 1 B-box. In proteins that do not contain RING or coiled-coil domains, the B-box domain is primarily type 2. Many type 2 B-box proteins are involved in ubiquitinylation. Proteins containing a B-box zinc finger domain include transcription factors, ribonucleoproteins and proto-oncoproteins; for example, MID1, MID2, TRIM9, TNL, TRIM36, TRIM63, TRIFIC, NCL1 and CONSTANS-like proteins [].The microtubule-associated E3 ligase MID1 () contains a type 1 B-box zinc finger domain. MID1 specifically binds Alpha-4, which in turn recruits the catalytic subunit of phosphatase 2A (PP2Ac). This complex is required for targeting of PP2Ac for proteasome-mediated degradation. The MID1 B-box coordinates two zinc ions and adopts a beta/beta/alpha cross-brace structure similar to that of ZZ, PHD, RING and FYVE zinc fingers [, ].

Publication Counts Displayer

1 Child Features

DB identifier Name Short Name Type
IPR020457 Zinc finger, B-box, chordata Znf_B-box_chordata Domain

0 Contains

4 Cross References

Identifier
Source . Name

Subject . Primary Identifier
PF00643 PFAM IPR000315
PS50119 PROFILE IPR000315
SM00336 SMART IPR000315
G3DSA:4.10.45.10 GENE3D IPR000315

3 Data Sets

Name URL
Swiss-Prot data set http://ca.expasy.org/sprot
InterPro data set  
InterPro GO Annotation data set  

0 Found In

2 GO Annotation


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
Zinc finger, B-box   GO:0008270 zinc ion binding
Zinc finger, B-box   GO:0005622 intracellular

2 Ontology Annotations


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
Zinc finger, B-box   GO:0008270 zinc ion binding
Zinc finger, B-box   GO:0005622 intracellular

0 Parent Features

158 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0293057 M9MRI4 Drosophila melanogaster
FBpp0079685 Q86P21 Drosophila melanogaster
FBpp0080702 Q8MQJ9 Drosophila melanogaster
FBpp0307610 M9MSJ1 Drosophila melanogaster
FBpp0083320 Q9VDK5 Drosophila melanogaster
FBpp0084258 Q8IMS5 Drosophila melanogaster
FBpp0084259 Q9VBP7 Drosophila melanogaster
FBpp0079210 Q9VLR7 Drosophila melanogaster
FBpp0071238 Q9W378 Drosophila melanogaster
FBpp0309300 M9PH32 Drosophila melanogaster
FBpp0289357 Q9V4M2 Drosophila melanogaster
FBpp0289844 A8WHL4 Drosophila melanogaster
FBpp0288118 Q29GC6 Drosophila pseudoobscura
FBpp0287812 Q29KR7 Drosophila pseudoobscura
FBpp0280034 Q29ML5 Drosophila pseudoobscura
FBpp0287278 Q29K31 Drosophila pseudoobscura
FBpp0278286 Q28YH9 Drosophila pseudoobscura
FBpp0282817 Q29BS0 Drosophila pseudoobscura
FBpp0282199 B5DY13 Drosophila pseudoobscura
FBpp0159801 B4K8F5 Drosophila mojavensis
FBpp0163210 B4KKF7 Drosophila mojavensis
FBpp0164938 B4L4B6 Drosophila mojavensis
FBpp0166224 B4KGW7 Drosophila mojavensis
FBpp0169014 B4KQ51 Drosophila mojavensis
FBpp0172549 B4K8M8 Drosophila mojavensis
FBpp0224750 B4M3Y2 Drosophila virilis
FBpp0225386 B4M4M5 Drosophila virilis
FBpp0229667 B4MCW7 Drosophila virilis
FBpp0232663 B4M942 Drosophila virilis
FBpp0232871 B4ME25 Drosophila virilis