In molecular biology, the AN1-type zinc finger domain, which has a dimetal (zinc)-bound alpha/beta fold. This domain was first identified as a zinc finger at the C terminus of AN1 SWISSPROT, a

ubiquitin-like protein Ubiquitin-like proteins (UBLs) are a family of small proteins involved in post-translational modification of other proteins in a cell (biology), cell, usually with a regulatory protein, regulatory function. The UBL protein family derives its name ...

in ''Xenopus laevis''. The AN1-type zinc finger contains six conserved

cysteine Cysteine (; symbol Cys or C) is a semiessential proteinogenic amino acid with the chemical formula, formula . The thiol side chain in cysteine enables the formation of Disulfide, disulfide bonds, and often participates in enzymatic reactions as ...

s and two

histidines Histidine (symbol His or H) is an essential amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated –NH3+ form under biological conditions), a carboxylic acid group (which is in the d ...

that could potentially coordinate 2 zinc

atom Atoms are the basic particles of the chemical elements. An atom consists of a atomic nucleus, nucleus of protons and generally neutrons, surrounded by an electromagnetically bound swarm of electrons. The chemical elements are distinguished fr ...

s. Certain stress-associated

proteins Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, re ...

(SAP) contain AN1 domain, often in combination with A20 zinc finger domains (SAP8) or C2H2 domains (SAP16). For example, the

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

protein Znf216 has an A20

zinc-finger A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) which stabilizes the fold. The term ''zinc finger'' was originally coined to describe the finger-like appearance of a hy ...

at the N terminus and an AN1 zinc-finger at the C terminus, acting to negatively

regulate Regulate may refer to: * Regulation Regulation is the management of complex systems according to a set of rules and trends. In systems theory, these types of rules exist in various fields of biology and society, but the term has slightly diff ...

the NFkappaB

activation In chemistry and biology, activation is the process whereby something is prepared or excited for a subsequent reaction. Chemistry In chemistry, "activation" refers to the reversible transition of a molecule into a nearly identical chemical or ...

pathway and to

interact Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization advocating for the legal and human rights of children with intersex traits. The organization was founded in 2006 and fo ...

with components of the

immune response An immune response is a physiological reaction which occurs within an organism in the context of inflammation for the purpose of defending against exogenous factors. These include a wide variety of different toxins, viruses, intra- and extracellula ...

like RIP, IKKgamma and TRAF6. The

of Znf216 with IKK-gamma and RIP is mediated by the A20 zinc-finger domain, while its interaction with TRAF6 is mediated by the AN1 zinc-finger domain; therefore, both zinc-finger domains are involved in regulating the

immune In biology, immunity is the state of being insusceptible or resistant to a noxious agent or process, especially a pathogen or infectious disease. Immunity may occur naturally or be produced by prior exposure or immunization. Innate and adaptive ...

response. The AN1 zinc finger domain is also found in proteins containing a ubiquitin-like domain, which are involved in the

ubiquitination Ubiquitin is a small (8.6 kDa) regulatory protein found in most tissues of eukaryotic organisms, i.e., it is found ''ubiquitously''. It was discovered in 1975 by Gideon Goldstein and further characterized throughout the late 1970s and 19 ...

pathway. Proteins containing an AN1-type zinc finger include: *Ascidian posterior end mark 6 (pem-6) protein . *

Human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

AWP1 protein (associated with PRK1), which is expressed during early

embryogenesis An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male ...

. *Human

immunoglobulin An antibody (Ab) or immunoglobulin (Ig) is a large, Y-shaped protein belonging to the immunoglobulin superfamily which is used by the immune system to identify and neutralize antigens such as pathogenic bacteria, bacteria and viruses, includin ...

mu binding protein 2 (SMUBP-2),

mutations In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosi ...

which cause muscular atrophy with respiratory distress type 1. AN1-type zinc finger domains are widely present across diverse "

Euryarchaeota Methanobacteriota is a phylum in the domain Archaea. Taxonomy The phylum ''Methanobacteriota'' was introduced to prokaryotic nomenclature in 2023. It contains following classes: *Archaeoglobi Garrity & Holt (2002) *Halobacteria Grant ''et al ...

" and

Nitrososphaerota The Nitrososphaerota (syn. Thaumarchaeota) are a phylum of the Archaea proposed in 2008 after the genome of '' Cenarchaeum symbiosum'' was sequenced and found to differ significantly from other members of the hyperthermophilic phylum Thermopr ...

, where they are often fused to membrane-associated peptidase domains such as the rhomboid family serine peptidase, transglutaminase-like thiol peptidases of the

papain Papain, also known as papaya proteinase I, is a cysteine protease () enzyme present in papaya (''Carica papaya'') and mountain papaya (''Vasconcellea cundinamarcensis''). It is the namesake member of the papain-like protease family. It has wi ...

fold, and Zn-dependent

metallopeptidase A metalloproteinase, or metalloprotease, is any protease enzyme whose catalytic mechanism involves a metal. An example is ADAM12 which plays a significant role in the fusion of muscle cells during embryo development, in a process known as myoge ...

s. Archaeal AN1 domains are also linked to transmembrane helices, and domains such as DNAJ and SCP/PR1. These fusions suggest membrane-associated roles for AN1 domain containing proteins in archaea, such as in the proteolytic processing of polypeptides and in regulating protein folding or stability. The architectural syntax is remarkably similar to that of the prokaryotic

B-box zinc finger In molecular biology the B-box-type zinc finger domain is a short protein domain of around 40 amino acid 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 a ...

and LIM domains.

References

{{InterPro content, IPR000058 Protein domains