LDHB encodes the B (also called H, "heart") subunit of L-lactate dehydrogenase (LDH; EC 1.1.1.27), a cytosolic NAD-dependent oxidoreductase. It catalyses the reversible, stereospecific interconversion of pyruvate + NADH + H+ and L-lactate + NAD+. Catalytically active LDH is a tetramer assembled in variable ratios from LDHA (M) and LDHB (H) subunits, producing the five classic isoenzymes (M4 through H4). LDHB-rich isoenzymes (H4) are kinetically tuned to favour the oxidation of L-lactate back to pyruvate and predominate in oxidative tissues such as heart and kidney that consume lactate as a metabolic fuel, whereas LDHA-rich isoenzymes favour the reduction of pyruvate to lactate during fermentative glycolysis. LDHB also participates in cytosolic NAD+/NADH redox balance. Loss-of-function LDHB variants cause lactate dehydrogenase B (H-subunit) deficiency, a generally benign condition of interest chiefly to laboratory medicine.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0019244 pyruvate fermentation to lactate | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: Phylogenetic (IBA) annotation to the pyruvate-to-lactate fermentation process for the LDH family node. LDHB is a bona fide L-lactate dehydrogenase and catalyses this reversible reaction, so the annotation is biologically correct at the family level, but its named direction (pyruvate -> lactate, fermentation) is the direction favoured by the LDHA (M) subunit; the LDHB-rich H4 isoenzyme is kinetically tuned to the reverse (lactate -> pyruvate) direction in oxidative tissues. Reason: The reaction is correctly assigned to the family, but for LDHB specifically the fermentation (lactate-producing) direction is not the physiologically dominant role; the lactate-oxidising direction is more characteristic. Keep as non-core; the core metabolic role is better captured by lactate/pyruvate metabolic process. Supporting Evidence: PMID:27618187 it has been suggested that LDHA preferentially reduces pyruvate to lactate, while LDHB supports conversion of lactate to pyruvate in cells that utilize lactate as a nutrient source for oxidative metabolism or gluconeogenesis |
| GO:0004459 L-lactate dehydrogenase (NAD+) activity | IBA GO_REF:0000033 | ACCEPT | Summary: Phylogenetic (IBA) assignment of the core catalytic molecular function, L-lactate dehydrogenase (NAD+) activity (EC 1.1.1.27). This is the defining activity of LDHB and is corroborated by direct enzymatic, structural, and orthology evidence. Reason: This is the core molecular function of LDHB, strongly supported across experimental (PMID:11276087, PMID:27618187), phylogenetic, and electronic evidence. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Reaction=(S)-lactate + NAD(+) = pyruvate + NADH + H(+); PMID:11276087 Lactate dehydrogenase (LDH) interconverts pyruvate and lactate with concomitant |
| GO:0005739 mitochondrion | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: Phylogenetic (IBA) annotation placing LDHB activity in the mitochondrion. A minority of experimental work (PMID:27618187) reports LDHB association with the inner mitochondrial membrane and mitochondrial LDH activity, but the canonical, dominant localization of LDH is cytosolic. Reason: There is experimental support for a mitochondrial pool of LDHB, but this is a non-canonical, still-debated localization for a classically cytosolic glycolytic enzyme. Retain as non-core rather than a core location. Supporting Evidence: PMID:27618187 gold-labeled LDHB localizes to the inner mitochondrial membrane |
| GO:0003824 catalytic activity | IEA GO_REF:0000002 | MARK AS OVER ANNOTATED | Summary: InterPro2GO electronic mapping to the root catalytic activity term. Correct but far too general given the well-defined L-lactate dehydrogenase (NAD+) activity. Reason: Uninformative parent of the specific enzymatic function; the precise MF term GO:0004459 is annotated with strong experimental evidence and should be preferred. |
| GO:0004459 L-lactate dehydrogenase (NAD+) activity | IEA GO_REF:0000120 | ACCEPT | Summary: Electronic (multi-method IEA) assignment of the core L-lactate dehydrogenase (NAD+) activity, consistent with the EC 1.1.1.27 / RHEA:23444 mapping and with experimental evidence. Reason: Correct core molecular function, redundant with but consistent with the experimental and phylogenetic annotations of the same term. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Reaction=(S)-lactate + NAD(+) = pyruvate + NADH + H(+); |
| GO:0005737 cytoplasm | IEA GO_REF:0000120 | ACCEPT | Summary: Electronic assignment of the cytoplasm, consistent with UniProt subcellular location and with LDH being a soluble cytosolic glycolytic enzyme. Reason: Correct, though the more specific cytosol (GO:0005829) is the preferred core location. Cytoplasm is a valid broader statement. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm. Mitochondrion inner membrane |
| GO:0005743 mitochondrial inner membrane | IEA GO_REF:0000044 | KEEP AS NON CORE | Summary: Electronic annotation derived from the UniProt Subcellular Location keyword mapping (Mitochondrion inner membrane), which in turn rests on the experimental report PMID:27618187. This is a non-canonical localization for LDHB. Reason: Supported experimentally (PMID:27618187) via the UniProt subcellular location, but a minority/debated localization; the core location is cytosolic. Keep as non-core. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm. Mitochondrion inner membrane |
| GO:0016491 oxidoreductase activity | IEA GO_REF:0000002 | MARK AS OVER ANNOTATED | Summary: InterPro2GO electronic mapping to the general oxidoreductase activity term. Correct but too general. Reason: Parent of the specific L-lactate dehydrogenase (NAD+) activity; uninformative given the well-supported specific MF term. |
| GO:0016616 oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP as acceptor | IEA GO_REF:0000002 | MARK AS OVER ANNOTATED | Summary: InterPro2GO electronic mapping to an intermediate oxidoreductase term describing the CH-OH-group / NAD(P)-acceptor chemistry. Accurate for LDH chemistry but less specific than L-lactate dehydrogenase (NAD+) activity. Reason: Correct grandparent-level chemistry but redundant with the specific MF term GO:0004459, which should be preferred. |
| GO:0005515 protein binding | IPI PMID:21044950 Genome-wide YFP fluorescence complementation screen identifi... | MARK AS OVER ANNOTATED | Summary: IntAct two-hybrid/interaction datum with TERF1 (P54274). Bare protein binding conveys no specific function. Reason: Uninformative generic protein-binding annotation from a high-throughput interaction screen; not a core function and no specific molecular function can be inferred. Retained per policy rather than removed. |
| GO:0005515 protein binding | IPI PMID:21988832 Toward an understanding of the protein interaction network o... | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with LDHA (P00338), consistent with formation of mixed M/H LDH tetramers, but captured only as generic protein binding. Reason: The underlying LDHA interaction is biologically real (heterotetramer assembly), but the bare protein binding term is uninformative; the tetramer relationship is better captured by identical protein binding / oxidoreductase complex. |
| GO:0005515 protein binding | IPI PMID:24725412 Ribosomal protein s15 phosphorylation mediates LRRK2 neurode... | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with LRRK2 (Q5S007) from a Parkinson-disease study. Bare protein binding, no specific function implied for LDHB. Reason: Uninformative generic protein-binding annotation; not a core function. |
| GO:0005515 protein binding | IPI PMID:25416956 A proteome-scale map of the human interactome network. | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with LDHA isoform (P00338-3) from a proteome-scale interactome map. Bare protein binding. Reason: Uninformative generic protein-binding annotation from a high-throughput interactome study; not a core function. |
| GO:0005515 protein binding | IPI PMID:25910212 Widespread macromolecular interaction perturbations in human... | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with LDHA isoform (P00338-3) from a study of interaction perturbations in genetic disorders. Bare protein binding. Reason: Uninformative generic protein-binding annotation; not a core function. |
| GO:0005515 protein binding | IPI PMID:28514442 Architecture of the human interactome defines protein commun... | MARK AS OVER ANNOTATED | Summary: IntAct interaction data (LDHA P00338, LDHC P07864) from an interactome community study. Consistent with LDH-family tetramer assembly but recorded as generic protein binding. Reason: Uninformative generic protein-binding term; the biologically relevant LDH-family subunit interactions are better captured elsewhere. |
| GO:0005515 protein binding | IPI PMID:31515488 Extensive disruption of protein interactions by genetic vari... | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with LDHA (P00338) from a study of variant-driven interaction disruption. Bare protein binding. Reason: Uninformative generic protein-binding annotation; not a core function. |
| GO:0005515 protein binding | IPI PMID:32296183 A reference map of the human binary protein interactome. | MARK AS OVER ANNOTATED | Summary: IntAct interaction data (SDCBP O00560, LDHA isoform P00338-3) from a reference binary interactome map. Bare protein binding. Reason: Uninformative generic protein-binding annotation from a high-throughput screen; not a core function. |
| GO:0005515 protein binding | IPI PMID:32814053 Interactome Mapping Provides a Network of Neurodegenerative ... | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with HTT (P42858) from a neurodegenerative-disease interactome study. Bare protein binding. Reason: Uninformative generic protein-binding annotation; not a core function. |
| GO:0005515 protein binding | IPI PMID:33961781 Dual proteome-scale networks reveal cell-specific remodeling... | MARK AS OVER ANNOTATED | Summary: IntAct interaction data (LDHA P00338, LDHC P07864) from a cell-specific interactome remodeling study. LDH-family subunit interactions recorded as generic protein binding. Reason: Uninformative generic protein-binding term; the relevant subunit interactions are better represented by the tetramer/complex annotations. |
| GO:0005515 protein binding | IPI PMID:35271311 OpenCell: Endogenous tagging for the cartography of human ce... | MARK AS OVER ANNOTATED | Summary: IntAct interaction data (LDHA P00338, LDHC P07864) from the OpenCell endogenous-tagging interactome. Bare protein binding. Reason: Uninformative generic protein-binding annotation; not a core function. |
| GO:0005515 protein binding | IPI PMID:40205054 Multimodal cell maps as a foundation for structural and func... | MARK AS OVER ANNOTATED | Summary: IntAct interaction datum with LDHC (P07864) from a multimodal cell-map study. Bare protein binding. Reason: Uninformative generic protein-binding annotation; not a core function. |
| GO:0042802 identical protein binding | IPI PMID:25416956 A proteome-scale map of the human interactome network. | KEEP AS NON CORE | Summary: IntAct self-interaction (P07195 with P07195), reflecting the homotetrameric assembly of the LDHB (H4) isoenzyme. Reason: Biologically meaningful (LDHB homotetramerization) and more informative than bare protein binding, but the self-association is a structural feature supporting the complex rather than the core catalytic function. Keep as non-core. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Homotetramer (PubMed:11276087) |
| GO:0042802 identical protein binding | IPI PMID:25502805 A massively parallel pipeline to clone DNA variants and exam... | KEEP AS NON CORE | Summary: IntAct self-interaction (P07195 with P07195) from a variant-cloning / molecular-phenotype pipeline, again reflecting LDHB homotetramerization. Reason: Consistent with homotetramer assembly; informative structural annotation but not the core catalytic function. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Homotetramer (PubMed:11276087) |
| GO:0042802 identical protein binding | IPI PMID:31515488 Extensive disruption of protein interactions by genetic vari... | KEEP AS NON CORE | Summary: IntAct self-interaction (P07195 with P07195), reflecting LDHB homotetramerization. Reason: Consistent with homotetramer assembly; informative structural annotation but not the core catalytic function. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Homotetramer (PubMed:11276087) |
| GO:0042802 identical protein binding | IPI PMID:32296183 A reference map of the human binary protein interactome. | KEEP AS NON CORE | Summary: IntAct self-interaction (P07195 with P07195) from the reference binary interactome, reflecting LDHB homotetramerization. Reason: Consistent with homotetramer assembly; informative structural annotation but not the core catalytic function. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Homotetramer (PubMed:11276087) |
| GO:0004457 lactate dehydrogenase activity | IEA GO_REF:0000107 | ACCEPT | Summary: Ensembl orthology (IEA) assignment of lactate dehydrogenase activity, the immediate parent of the NAD+-specific L-lactate dehydrogenase activity. Reason: Correct and consistent with the core function; a slightly broader phrasing of the same catalytic activity. Acceptable as-is. Supporting Evidence: PMID:11276087 Lactate dehydrogenase (LDH) interconverts pyruvate and lactate with concomitant |
| GO:0005829 cytosol | IEA GO_REF:0000107 | ACCEPT | Summary: Ensembl orthology (IEA) placement of LDHB activity in the cytosol, the canonical location of this glycolytic enzyme, concordant with the HPA IDA and Reactome TAS annotations to cytosol. Reason: Correct core subcellular location; strongly corroborated by IDA (HPA) and TAS (Reactome) evidence. |
| GO:0006089 lactate metabolic process | IEA GO_REF:0000107 | ACCEPT | Summary: Ensembl orthology (IEA) assignment to lactate metabolic process, capturing LDHB's role in the interconversion of lactate and pyruvate. Also independently supported by ComplexPortal IDA (PMID:15117937). Reason: Accurately reflects the core biological process in which LDHB participates (lactate/pyruvate interconversion), and is the process best matching the LDHB-favoured lactate-oxidising direction. Supporting Evidence: PMID:27618187 LDHB supports conversion of lactate to pyruvate in cells that utilize lactate as a nutrient source for oxidative metabolism or gluconeogenesis |
| GO:0019674 NAD+ metabolic process | IEA GO_REF:0000107 | KEEP AS NON CORE | Summary: Ensembl orthology (IEA) assignment to NAD+ metabolic process, reflecting that LDHB regenerates/consumes NAD+/NADH during the lactate-pyruvate reaction and thereby contributes to cytosolic redox balance. Reason: Biologically correct (the reaction interconverts NAD+ and NADH), but NAD+ metabolism is a downstream consequence of the catalytic activity rather than the core annotated function. Keep as non-core. Supporting Evidence: PMID:15117937 central to NAD(+) regeneration |
| GO:0019900 kinase binding | IEA GO_REF:0000107 | MARK AS OVER ANNOTATED | Summary: Ensembl orthology (IEA) transfer of a kinase-binding annotation from a rat ortholog. There is no specific experimental evidence that human LDHB binds a kinase as a defined molecular function. Reason: Orthology-transferred generic binding annotation with no clear functional relevance to LDHB's role; likely an over-annotation and not a core function. |
| GO:0042802 identical protein binding | IEA GO_REF:0000107 | KEEP AS NON CORE | Summary: Ensembl orthology (IEA) transfer of identical protein binding, consistent with the homotetrameric assembly of LDHB. Reason: Reflects LDHB homotetramerization; informative structural feature but not the core catalytic function. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Homotetramer (PubMed:11276087) |
| GO:0051287 NAD binding | IEA GO_REF:0000107 | ACCEPT | Summary: Ensembl orthology (IEA) assignment of NAD binding. LDHB is an NAD-dependent dehydrogenase with a Rossmann-fold NAD-binding domain and defined NAD(+)-binding residues, so this is a correct and informative molecular function. Reason: Correct; NAD binding is a genuine, structurally documented molecular function of LDHB (NAD-binding Rossmann domain; NAD(+) binding site residues in UniProt). Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt Reaction=(S)-lactate + NAD(+) = pyruvate + NADH + H(+); |
| GO:0005829 cytosol | IDA GO_REF:0000052 | ACCEPT | Summary: Direct immunofluorescence (HPA) localization of LDHB to the cytosol, the canonical location of this glycolytic enzyme. Reason: Experimentally supported core subcellular location, concordant with electronic and TAS cytosol annotations. |
| GO:0004459 L-lactate dehydrogenase (NAD+) activity | EXP PMID:11276087 Structural basis for altered activity of M- and H-isozyme fo... | ACCEPT | Summary: Experimental (structural/biophysical) demonstration of L-lactate dehydrogenase (NAD+) activity for human LDH-H, via crystallographic ternary complexes with NADH and substrate analog and kinetic characterization. Reason: This is the defining, experimentally established core molecular function of LDHB, characterized structurally and kinetically for the H isoform. Supporting Evidence: PMID:11276087 Lactate dehydrogenase (LDH) interconverts pyruvate and lactate with concomitant PMID:11276087 the H form, found mainly in cardiac muscle |
| GO:0006089 lactate metabolic process | IDA PMID:15117937 Identification and activity of a series of azole-based compo... | ACCEPT | Summary: ComplexPortal IDA annotation of the LDH complex to lactate metabolic process. LDH is central to lactate/pyruvate interconversion and NAD+ regeneration. Reason: Correctly captures the core biological process; LDHB participates in lactate metabolism as the H subunit of the LDH complex. Supporting Evidence: PMID:15117937 central to NAD(+) regeneration |
| GO:1990204 oxidoreductase complex | IPI PMID:15117937 Identification and activity of a series of azole-based compo... | ACCEPT | Summary: ComplexPortal assertion that LDHB is part of the L-lactate dehydrogenase (oxidoreductase) complex, i.e. the LDH tetramer. UniProt/ComplexPortal record the A/B (M/H) tetramer variants (CPX-6592/6594/6598/6599). Reason: Correct; catalytically active LDH is a tetramer, and LDHB is a constituent subunit. This appropriately captures the complex-level context of the enzyme. Supporting Evidence: PMID:27618187 Functional LDH is a homo or hetero tetramer composed of LDHA and LDHB subunits file:human/LDHB/LDHB-uniprot.txt Homotetramer (PubMed:11276087) |
| GO:0004459 L-lactate dehydrogenase (NAD+) activity | IDA PMID:27618187 Lactate metabolism is associated with mammalian mitochondria... | ACCEPT | Summary: Direct assay of LDHB (L-lactate dehydrogenase) activity in whole-cell and isolated mitochondrial lysates, confirming the core catalytic function. Reason: Experimentally supported core molecular function of LDHB. Supporting Evidence: PMID:27618187 the mitochondria had higher LDHB activity, further suggesting that LDHB activity is concentrated in mitochondria |
| GO:0005515 protein binding | IPI PMID:33406399 An Upstream Open Reading Frame in Phosphatase and Tensin Hom... | MARK AS OVER ANNOTATED | Summary: UniProt-curated IPI interaction with the PTEN-uORF micropeptide MP31 (C0HLV8). MP31 binds LDHB and inhibits mitochondrial LDH activity by competing for NAD+, acting as a regulatory circuit breaker of lactate-pyruvate conversion; the interaction is abolished by LDHB mutations D53A and R100A. Reason: This is the most biologically meaningful of the protein-binding annotations (a specific, functionally characterized regulatory interaction), but the term itself is the uninformative generic protein binding. Retained (not removed) per policy; a more specific enzyme-inhibitor / MP31-binding characterization would be preferable. Supporting Evidence: PMID:33406399 limits lactate-pyruvate conversion in mitochondria by PMID:33406399 competing with mitochondrial lactate dehydrogenase (mLDH) for |
| GO:0005743 mitochondrial inner membrane | IDA PMID:27618187 Lactate metabolism is associated with mammalian mitochondria... | KEEP AS NON CORE | Summary: TEM immunogold localization of LDHB to the inner mitochondrial membrane in HeLa cells, with concordant mitochondrial LDH activity in isolated mitochondria. A specific but non-canonical localization for this classically cytosolic enzyme. Reason: Experimentally supported (PMID:27618187), but a minority/debated localization; the dominant location of LDHB is cytosolic. Retain as non-core. Supporting Evidence: PMID:27618187 gold-labeled LDHB localizes to the inner mitochondrial membrane |
| GO:0045121 membrane raft | IDA PMID:25204797 Flotillin-1 facilitates toll-like receptor 3 signaling in hu... | MARK AS OVER ANNOTATED | Summary: Localization to membrane raft reported in a flotillin-1/TLR3 endothelial signaling study that used SILAC proteomics of raft/caveolae fractions. LDHB is a soluble cytosolic enzyme and its recovery in raft proteomic fractions most likely reflects abundant-protein co-purification rather than a functional raft localization. Reason: A soluble glycolytic enzyme is not expected to be a genuine membrane raft resident; this is likely a proteomic co-isolation artifact and an over-annotation. Supporting Evidence: PMID:25204797 Flotillin-1 and -2 are markers of membrane rafts |
| GO:0070062 extracellular exosome | HDA PMID:23533145 In-depth proteomic analyses of exosomes isolated from expres... | MARK AS OVER ANNOTATED | Summary: High-throughput proteomic detection of LDHB in urinary/prostatic-secretion exosome preparations. Abundant cytosolic enzymes are commonly detected in exosome proteomes without evidence of a functional role there. Reason: Cytosolic-enzyme detection in exosome proteomics; not a functional localization and not a core annotation. |
| GO:0016020 membrane | HDA PMID:19946888 Defining the membrane proteome of NK cells. | MARK AS OVER ANNOTATED | Summary: High-throughput proteomic detection of LDHB in an NK-cell membrane proteome preparation. Non-specific membrane assignment for a soluble enzyme. Reason: Generic membrane assignment for a cytosolic protein from a proteomic membrane-fraction study; likely co-isolation and an over-annotation. |
| GO:0070062 extracellular exosome | HDA PMID:19056867 Large-scale proteomics and phosphoproteomics of urinary exos... | MARK AS OVER ANNOTATED | Summary: High-throughput proteomic detection of LDHB in urinary exosomes. Reason: Cytosolic-enzyme detection in exosome proteomics; not a functional localization and not a core annotation. |
| GO:0070062 extracellular exosome | HDA PMID:20458337 MHC class II-associated proteins in B-cell exosomes and pote... | MARK AS OVER ANNOTATED | Summary: High-throughput proteomic detection of LDHB in B-cell exosomes. Reason: Cytosolic-enzyme detection in exosome proteomics; not a functional localization and not a core annotation. |
| GO:0005829 cytosol | TAS Reactome:R-HSA-70510 | ACCEPT | Summary: Reactome traceable-author-statement placing LDHB in the cytosol in the context of LDH tetramer oxidises LACT to PYR, the lactate-oxidising direction favoured by the LDHB-rich isoenzyme. Reason: Correct core cytosolic location, consistent with IDA and IEA cytosol annotations and with the canonical glycolytic-enzyme localization. |
| GO:0005829 cytosol | TAS Reactome:R-HSA-71849 | ACCEPT | Summary: Reactome traceable-author-statement placing LDHB in the cytosol in the context of LDH tetramer reduces PYR to LACT. Reason: Correct core cytosolic location, redundant with but consistent with the other cytosol annotations. |
| GO:0005737 cytoplasm | TAS PMID:16130169 Proteomics of human umbilical vein endothelial cells applied... | ACCEPT | Summary: Traceable-author-statement (UniProt) cytoplasm localization derived from a HUVEC proteomics study. Consistent with the soluble cytoplasmic nature of LDHB. Reason: Correct broader localization; the more specific cytosol is preferred as the core location. Supporting Evidence: file:human/LDHB/LDHB-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm. Mitochondrion inner membrane |
| GO:0004459 L-lactate dehydrogenase (NAD+) activity | TAS PMID:8314553 Analysis of a genetic mutation in an electrophoretic variant... | ACCEPT | Summary: Traceable-author-statement of L-lactate dehydrogenase (NAD+) activity, from a study characterizing an electrophoretic LDH-B(H) subunit variant (K7E) with decreased heat stability and slightly reduced activity. Reason: Correct core molecular function; the paper explicitly concerns the human LDH-B (H) subunit and its enzymatic activity. Supporting Evidence: PMID:8314553 An electrophoretic variant of the lactate dehydrogenase (LDH)-B(H) subunit was |
Loading supporting content…
Download this section (compressed HTML)Q: Is the mitochondrial (inner-membrane) pool of LDHB a genuine, functionally significant localization in vivo, or is it largely restricted to specific cell types (e.g. fermenting cancer cells) and experimental conditions?
Q: To what extent does the MP31 (PTEN-uORF) circuit-breaker regulation of LDHB operate in normal physiology versus tumour metabolism?
Experiment: Compartment-resolved activity assays (cytosol vs mitochondrial sub-fractions) across oxidative and glycolytic human tissues to quantify the physiological contribution of any mitochondrial LDHB pool.
Experiment: Structure-guided kinetic comparison of purified LDHB homotetramer versus defined M/H heterotetramers to quantify the directional (lactate to pyruvate) preference under physiological substrate/redox conditions.
Loading supporting content…
Download this section (compressed HTML)Loading supporting content…
Download this section (compressed HTML)