B-Box-type zinc finger;

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                   ....*....|....*....|....*....|....*....|....*..
gi 1121825184   55 MKGKVCGQCETKNALLVCLECGEDYCGSCFAKIHQKgalklHRMIPL 101
Cdd:smart00336   1 QRAPKCDSHGDEPAEFFCEECGALLCRTCDEAEHRG-----HTVVLL 42

B-box-type 1 zinc finger (Bbox1); The B-box-type zinc finger is a short zinc binding domain of around 40 amino acid residues in length. It has been found in transcription factors, ribonucleoproteins and proto-oncoproteins, such as 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). The B-box-type zinc finger often presents in combination with other motifs, like RING zinc finger, NHL motif, coiled-coil or RFP domain, in functionally unrelated proteins, most likely mediating protein-protein interactions. Based on different consensus sequences and the spacing of the 7-8 zinc-binding residues, the B-box-type zinc fingers can be divided into two groups, type 1 (Bbox1: C6H2) and type 2 (Bbox2: CHC3H2). This family corresponds to the type 1 B-box (Bbox1).

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                  ....*....|....*....|....*....|....*....|....
gi 1121825184  59 VCGQCETKNALLVCLECGEDYCGSCFAKIHQKG-ALKLHRMIPL 101
Cdd:cd19757     1 LCDECEEREATVYCLECEEFLCDDCSDAIHRRGkLTRSHKLVPL 44

B-Box-type zinc finger;

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                   ....*....|....*....|....*....|....*....|....*..
gi 1121825184   55 MKGKVCGQCETKNALLVCLECGEDYCGSCFAKIHQKgalklHRMIPL 101
Cdd:smart00336   1 QRAPKCDSHGDEPAEFFCEECGALLCRTCDEAEHRG-----HTVVLL 42

first B-box-type 2 zinc finger found in tripartite motif-containing protein 23 (TRIM23) and similar proteins; TRIM23, also known as ADP-ribosylation factor domain-containing protein 1, GTP-binding protein ARD-1, or RING finger protein 46 (RNF46), is an E3 ubiquitin-protein ligase belonging to the C-IX subclass of TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, two Bbox2, and a coiled coil region, as well as C-terminal ADP ribosylation factor (ARF) domains. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif. TRIM23 is involved in nuclear factor (NF)-kappaB activation. It mediates atypical lysine 27 (K27)-linked polyubiquitin conjugation to NF-kappaB essential modulator NEMO, also known as IKKgamma, which plays an important role in the NF-kappaB pathway, and this conjugation is essential for TLR3- and RIG-I/MDA5-mediated antiviral innate and inflammatory responses. It also regulates adipocyte differentiation via stabilization of the adipogenic activator peroxisome proliferator-activated receptor gamma (PPARgamma) through atypical ubiquitin conjugation to PPARgamma. Moreover, TRIM23 interacts with and polyubiquitinates yellow fever virus (YFV) NS5 to promote its binding to STAT2 and trigger type I interferon (IFN-I) signaling inhibition.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1121825184  59 VCGQCETKNALLVCLECGEDYCGSCFAKIHQKGALKLHRMIPLQAK 104
Cdd:cd19773     4 PCDENEDHEATLYCTVCSTNLCEECFTSTHSTKTLSKHRRVPLSEK 49

B-box-type 1 zinc finger found in promyelocytic leukemia protein (PML) and similar proteins; Protein PML, also known as RING finger protein 71 (RNF71) or tripartite motif-containing protein 19 (TRIM19), is predominantly a nuclear protein with a broad intrinsic antiviral activity. It is the eponymous component of PML nuclear bodies (PML NBs) and has been implicated in a wide variety of cellular processes, including DNA damage signaling, apoptosis, and transcription. PML interferes with the replication of many unrelated viruses, including human immunodeficiency virus 1 (HIV-1), human foamy virus (HFV), poliovirus, influenza virus, rabies virus, EMCV, adeno-associated virus (AAV), and vesicular stomatitis virus (VSV). It also selectively interacts with misfolded proteins through distinct substrate recognition sites, and conjugates these proteins with the small ubiquitin-like modifiers (SUMOs) through its SUMO ligase activity. PML belongs to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and a coiled coil region, as well as an uncharacterized region positioned C-terminal to the RBCC domain. The type 1 B-box (Bbox1) zinc finger is characterized by a C6H2 zinc-binding consensus motif.

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                  ....*....|....*....|....*....|....*....|....*
gi 1121825184  59 VCGQCETKNALLVCLECGEDYCGSCFaKIHQKGALKL-HRMIPLQ 102
Cdd:cd19804     3 MCNRCSESEAEFWCSECEEFLCRKCF-EAHQRFKKRKkHEALRLA 46