Transmembrane protein 132B is a protein encoding gene that encodes the human TMEM132B protein. Variant 1 of human TMEM132B consists of 1078 amino acids.

Gene The TMEM132B gene is located on chromosome 12 at 12q24.31 and contains 18 exons. In humans, exons 1-9 include the coding region and exons 10-18 include only 3' untranslated region (UTR). TMEM132B primarily localizes in the cytoplasm.

Expression Human TMEM132B is expressed in the brain as well as the fetal brain. Small amounts of TMEM132B have been found in the thyroid, salivary gland, prostate, intestinal organs, and the placenta.

TMEM132B is expressed under various conditions, most of which occur in the brain. One example of TMEM132B expression in the brain is seen in Parkinson's disease, particularly in the substantia nigra. The substantia nigra is located in the basal ganglia of the brain and is essential for controlling body movements.Professional, C. C. medical. (2025, March 19). Substantia nigra (SN): What it is, Function & Anatomy. Cleveland Clinic. https://my.clevelandclinic.org/health/body/23010-substantia-nigra-sn Microarray dataParkinson’s disease: substantia nigra (HG-U133B) microarray suggests that individuals with Parkinson's disease have moderate to low TMEM132B expression (68%–75%) compared to those without Parkinson's disease (75%–91%).

Protein The human TMEM132B gene encodes a protein of 1078 amnio acids in length. Human TMEME132B has one transmembrane region and three N-glycosylation sites. TMEM132B has a predicted molecular weight of 119.5 kD and a predicted isoelectric point (pI) of 5.

Interacting Proteins TMEM132B has different proteins that interact with it. There are four main proteins that were found to have interactions with TMEM132B. Of the four that were found, two are located in the cytoplasm, one is in the cytosol, and one is in the postsynaptic membrane (see table 1). + Table 1. Proteins that interact with TMEM132B and their function. Full Name Abbreviated Name Protein Function Basis of Identification Cell Location Guanylate kinase-associated protein DIgap1 Plays a role in the function and structure of synapse and is a scaffolding protein. Anti bait co-immunoprecipitation Intracellular side of the postsynaptic membrane SNAP-25-interacting protein Scrin1 In the SNARE complex. Regulates kinase activity and postsynaptic organization in the cytoplasm and cytoskeleton. Cross-linking study Cytoplasm Ring finger protein 123 RNF123 Innate antiviral signaling inhibitor. Has E3 ubiquitin ligase activity. Cyclin-dependent kinase inhibitor. Affinity Capture-MS Cytoplasm and nucleus Peptidylprolyl isomerase A (cyclophilin A) PPIA Protein folding enzyme. Important in protein folding and catalyzing certain peptide bonds. Cross-Linking-MS (XL-MS) Cytosol. It can be secreted to extracellular regions

Evolution

Orthologs Ortholog sequences for TMEM132B were found in primates, mammals, reptiles, birds, and amphibians. Amphibians were the last taxon group found that contained TMEM132B. Ortholog sequences were organized by median date of divergence with the farthest date of divergence being 352 MYA. See Table 2. + Table 2. 20 orthologs for TMEM132B.NCBI BLASTClustal OmegaTimeTree Seq Genus species Common name Taxon Date of Div (MYA) Seq Length (AA) Seq ID % Seq similarity % 1 Homo sapiens Humans Primates 0 1078 100 100 2 Theropithecus gelada Gelada Primates 29 1078 98.8 99.1 3 Chlorocebus sabaeus Green Monkey Primates 29 1083 96.3 97.1 4 Lemur catta Ring-Tailed Lemur Primates 74 1183 84.8 87.1 5 Mus musculus House Mouse Rodentia 87 1078 84.7 90.8 6 Bubalus bubalis Water Buffalo Even-Toed Ungulates 94 1084 86.4 92.4 7 Lynx rufus Bobcat Carnivore 94 1099 84.8 91.1 8 Monodelphis domestica Gray Short-Tailed Opossum Didelphidae 160 709 84.65 65.0 9 Vombatus ursinus Common Wombat Diprotodontia 160 1066 77.6 86.310 Tachyglossus aculeatus Short-Beaked Echidna Monotremata 180 1094 72.9 83.311 Terrapene triunguis Three-Toed Box Turtle Testudines 319 1090 71.8 82.212 Gallus gallus Chicken Aves 319 1062 71.3 82.613 Rhea pennata Darwin's Rhea Aves 319 1086 70.1 81.714 Gymnogyps californianus California Condor Aves 319 1087 69.9 81.015 Rhinatrema bivittatum Two-Lined Caecilian Caecilian 352 1087 66.3 79.316 Pelobates fuscus Common Spadefoot Pelobatidae 352 1108 62.1 74.617 Bufo bufo Common Toad Anura 352 1089 62.0 75.618 Pleurodeles waltl Iberian Ribbed Newt Salamander 352 1097 61.7 73.719 Xenopus laevis African Clawed Frog Anura 352 1101 59.8 74.020 Ambystoma mexicanum Axolotl Salamander 352 1122 59.7 73.0

Paralogs TMEM132B has a lot of paralogs in humans. The main paralogs were TMEM132A, TMEM132C, TMEM132D, and TMEM132E. These four paralogs are what make up the human TMEM132 family. + Table 3. Paralogs for TMEM132B. Sequence Accession # Seq Length (AA) E-value Identity % TMEM132B NP_443139.2 1078 0 100% TMEM132D KAI2568702.1 637 0 52.50% TMEM132C KAI2568693.1 1108 0 52.21% TMEM132E KAI2582325.1 1074 0 35.78% TMEM132A KAI2560231.1 1024 3.00E-133 34.37%

References