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 AN
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, usually with a regulatory function. The UBL protein family derives its name from the first member of the class ...

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 formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile. When present as a deprotonated catalytic residue, sometime ...

s and two histidines that could potentially coordinate 2 zinc

atom Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, and ...

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, respo ...

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

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

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+) in order to stabilize the fold. It was originally coined to describe the finger-like appearance of a hypothesized struc ...

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

activation Activation, in chemistry and biology, 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 using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...

with components of the

immune response An immune response is a reaction which occurs within an organism for the purpose of defending against foreign invaders. These invaders include a wide variety of different microorganisms including viruses, bacteria, parasites, and fungi which could ...

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 capability of multicellular organisms to resist harmful microorganisms. Immunity involves both specific and nonspecific components. The nonspecific components act as barriers or eliminators of a wide range of pathogens ...

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 1980s. Fo ...

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

Human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

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

embryogenesis An embryo is an initial stage of development of 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 sperm ...

. *Human

immunoglobulin An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...

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, mi ...

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

Euryarchaeota Euryarchaeota (from Ancient Greek ''εὐρύς'' eurús, "broad, wide") is a phylum of archaea. Euryarchaeota are highly diverse and include methanogens, which produce methane and are often found in intestines, halobacteria, which survive extre ...

" 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 Thermoprote ...

, 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 wide ...

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 myogen ...

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 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 ...

and LIM domains.

References

{{InterPro content, IPR000058 Protein domains