Metallothionein-1B (MT1B)

Metallothionein-1B (MT1B) is a low-molecular-weight, intracellular metal-binding protein that belongs to the metallothionein superfamily and plays a critical role in cellular metal ion homeostasis, particularly for zinc and copper[2][3][4][6]. MT1B is part of the MT1 subfamily and is encoded on chromosome 16q13, one of several highly homologous genes including other MT1 isoforms[1][6]. MT1B binds heavy metals through its high cysteine content, providing protection against metal toxicity and oxidative stress by sequestering excess metal ions and scavenging reactive oxygen species[2][3]. It is ubiquitously expressed, particularly in organs such as the liver, kidney, and intestine, and is rapidly induced in conditions of increased metal exposure, oxidative stress, or inflammation[1][4]. Functionally, MT1B regulates immune responses by modulating key signaling pathways, including STAT1/3, NF-κB, and PI3K/Akt, and is implicated in diseases such as cancer, autoimmune disorders, liver diseases (notably hepatic steatosis), neurodegenerative disorders, and inflammatory conditions[1][5]. Due to its inducible nature, MT1 and its isoforms like MT1B are studied as biomarkers for metal exposure and oxidative/inflammatory status, and are being investigated as potential therapeutic targets for modulating immune and inflammatory responses[2][5]. Currently, there are no specific drugs developed to target MT1B directly, but its functional modulation represents an area of ongoing research.

Other names

Metallothionein-1BMT1BMT1QMT-1BMT-IBMetallothionein-IBMT1MTPmetallothionein 1B (functional)metallothionein 1Qmetallothionein-IB

Metal chelation and detoxification (binding and sequestration of toxic metals); Negative regulation of STAT1/STAT3 pathways; Modulation of NF-κB and PI3K/Akt signaling; Regulation of cellular zinc and copper availability