| 2008 |
BHMT variant allozymes expressed in COS-1 cells showed no significant differences from wild type in enzyme activity or immunoreactive protein levels, but had statistically significant differences in apparent Km values, indicating altered substrate binding. BHMT2 protein could not be functionally expressed alone but was stabilized by co-transfection with BHMT and co-precipitated with BHMT, indicating a direct physical interaction between the two paralogs. |
COS-1 cell expression of variant allozymes, enzyme activity assays, immunoreactive protein quantification, Km determination, co-transfection and co-immunoprecipitation |
Molecular genetics and metabolism |
Medium |
18457970
|
| 2011 |
Full-length endogenous BHMT (45 kDa cytosolic enzyme) is cleaved in an autophagy-dependent (3-methyladenine-sensitive) manner in isolated rat hepatocytes, generating a novel N-terminal 10-kDa fragment (p10). The cleavage is performed by the asparaginyl proteinase legumain (inhibitable by AJN-230) and occurs primarily in amphisomes rather than lysosomes. This makes BHMT a useful probe/reporter for autophagic flux. |
Isolated rat hepatocytes, 3-methyladenine inhibition, specific legumain inhibitor (AJN-230), mass spectrometry identification of p10 fragment, leupeptin protection, asparagine inhibition of amphisome-lysosome fusion |
Autophagy |
High |
21610319
|
| 2011 |
A splicing variant of BHMT exon 4 generates a frameshift with a premature termination codon in exon 5, resulting in complete loss of BHMT enzymatic activity and undetectable protein expression in HepG2 hepatocellular carcinoma cells and 5 of 6 tumor samples; this variant is absent from normal adult and fetal liver. |
RT-qPCR, exon junction analysis and sequencing, Western blot, immunohistochemistry, enzyme activity assay in HepG2 cells and tumor tissue |
The international journal of biochemistry & cell biology |
High |
22138536
|
| 2011 |
Depletion of Bhmt in zebrafish morphants causes hypoplasia of liver, exocrine pancreas, and intestine, but paradoxically increases β-cell number. Genetic epistasis experiments showed that Bhmt depletion elevates sonic hedgehog (shh) transcript levels, and Bhmt depletion in Shh-deficient (syu) mutants failed to rescue the isletless phenotype, placing Shh downstream of Bhmt in the pathway controlling β-cell development. |
Antisense morpholino knockdown in zebrafish, genetic epistasis with syu (shh-null) mutant, qRT-PCR for shh transcripts, histological analysis of organ development |
Endocrinology |
High |
21952238
|
| 2015 |
The GST-BHMT fusion reporter is cleaved in lysosomes in an autophagy-dependent manner. Under nutrient-rich conditions, proteasome inhibition induces GST-BHMT processing through a mechanism distinct from starvation-induced autophagy: it does not require MTOR or PRKAA/AMPK, but requires cargo receptors SQSTM1/p62 and NBR1, and depends on ER stress signaling via ERN1/IRE1 and MAPK8/JNK1 (but not XBP1), regulating BCL2-BECN1 dissociation. Additionally, the multimerization domain of GST-BHMT is required for proteasome inhibition-induced processing but is dispensable for starvation-induced processing. |
GST-BHMT reporter fragmentation assay, pharmacological and genetic proteasome inhibition, siRNA knockdown of MTOR, AMPK, SQSTM1, NBR1, ERN1, MAPK8, XBP1, domain deletion mutagenesis |
Autophagy |
High |
25984893
|
| 2017 |
Bhmt-null mice develop elevated S-adenosylhomocysteine concentrations and preneoplastic foci in the liver (increased placental GST and CK8-18 activity starting at 12 weeks). Whole-genome methylation analysis identified differentially methylated CpGs leading to repression of Iqgap2 and F2rl2 genes, indicating that BHMT activity is required to maintain adequate DNA methylation and normal expression of these loci in liver. |
Bhmt-null mouse model, whole-genome bisulfite sequencing, RNA expression profiling, immunohistochemistry for preneoplastic markers, metabolite measurement (S-adenosylhomocysteine) |
FASEB journal |
High |
28179424
|
| 2021 |
BHMT is present in the nucleus of oligodendrocytes (confirmed by immunocytochemistry in human MO3.13 cell line, primary rat oligodendrocytes, and MS postmortem tissue). BHMT expression is increased ~2-fold after oxidative insult. Chromatin fractionation showed direct interaction of BHMT on chromatin, and co-IP demonstrated interaction between BHMT and DNMT3a. Betaine administration increased both histone methyltransferase and DNA methyltransferase activity, and this effect was dependent on BHMT expression (abolished by siRNA knockdown), establishing BHMT as a chromatin-associated regulator of epigenetic marks in oligodendrocytes. |
Immunocytochemistry, chromatin fractionation, co-immunoprecipitation, qRT-PCR, siRNA knockdown, histone and DNA methyltransferase activity assays |
PloS one |
Medium |
33975330
|
| 2023 |
After irradiation, SDC1 transports TGM2 from the cell membrane into the cytoplasm and to lysosomes via binding to FLOT1; TGM2 then recognizes BHMT on autophagosomes to coordinate the encounter between autophagosomes and lysosomes. This SDC1-TGM2-FLOT1-BHMT complex maintains autophagic flux in irradiated GBM cells and enhances radioresistance. |
Co-IP, immunofluorescence, mRFP-GFP-LC3 reporter, transmission electron microscopy, flow cytometry, colony formation, Western blot, qPCR in radioresistant GBM cells |
Theranostics |
Medium |
37441590
|
| 2023 |
In a monkey hydroxynonenal-injection model of hepatocyte injury, BHMT protein was carbonylated (~2-fold increase by proteomics) and showed increased cleavage without upregulation. Impaired rough ER caused deficient BHMT synthesis, contributing to hepatic steatosis consistent with BHMT's role in phosphatidylcholine metabolism via choline pathway. |
Proteomics (DIA), Western blot, immunohistochemistry, electron microscopy in monkey liver model |
Nutrients |
Low |
37111122
|
| 2024 |
Betaine upregulates BHMT expression, leading to increased NADPH production. Elevated NADPH in turn upregulates FTO expression. FTO then reduces m6A methylation in the CDS of Ppargc1α (PGC1α) mRNA, increasing PGC1α expression and inhibiting hepatic lipid accumulation, placing BHMT upstream in a betaine→BHMT→NADPH→FTO→m6A-PGC1α axis. |
Cell-based assays, siRNA knockdown, Western blot, m6A methylation quantification, gene expression analysis in NAFLD models |
The Journal of nutritional biochemistry |
Low |
39154792
|
| 2026 |
BHMT overexpression in renal cells reduces ROS production and apoptosis under hypoxia/reoxygenation by enhancing SAM synthesis, which increases DNMT activity, leading to methylation of the NOX4 promoter and suppression of NOX4 transcription and expression. Rescue assays confirmed BHMT-mediated protection is dependent on NOX4 downregulation. |
RT-qPCR, Western blot, MTT assay, flow cytometry, ROS assays, promoter methylation analysis, BHMT overexpression and rescue experiments in vitro and in vivo IRI model |
Archives of biochemistry and biophysics |
Medium |
41643883
|
| 2026 |
In murine hepatocytes, BRCA1 deficiency suppresses Bhmt expression. Concomitant knockdown of BRCA1 and BHMT in human hepatoma cells produced additive accumulation of DNA double-strand breaks and increased cell death susceptibility. BHMT repression under BRCA1-deficiency was associated with downregulation of choline metabolism (confirmed by metabolomics), identifying BHMT as a mediator of BRCA1's effects on choline metabolism and DNA damage response. |
Single nuclear RNA sequencing, siRNA knockdown in human hepatoma cells, DNA damage assays (DSBs), metabolomics in Brca1-deficient mice |
Scientific reports |
Medium |
41781465
|
| 2016 |
Betaine supplementation in MCD diet-fed rats reversed the reduction of methionine and SAM and elevation of homocysteine by inducing BHMT and MAT expression. In H4IIE cells (which express BHMT), betaine prevented homocysteine-induced reduction of pAMPK/pACC/pSREBP-1c/pLKB1, but not in HepG2 cells (which lack BHMT), demonstrating that BHMT expression is required for the betaine-mediated activation of the AMPK pathway and anti-lipogenic effect. |
Rat dietary model, cell-based assays in H4IIE and HepG2 cells, Western blot for phosphorylated signaling proteins, BHMT and MAT protein expression, homocysteine and SAM measurement |
Biochemical and biophysical research communications |
Medium |
27320863
|
| 2023 |
In Bhmt-KO mice, deletion of BHMT in the liver leads to homocysteine-induced ER stress, activation of hepatic transcription factor CREBH, and increased hepatic and plasma FGF21, which in turn promotes adipose browning and atrophy. This establishes a liver-to-adipose signaling axis downstream of BHMT loss. |
Bhmt-KO mouse model (C57Bl6/J background), histological analysis, gene expression profiling, metabolite/hormone measurements (Hcy, FGF21), ER stress marker analysis |
Heliyon |
Medium |
36755585
|