LDHA Mouse
Description
Recombinant LDHA Proteins from Mouse Sources
Mouse LDHA is commercially available as recombinant proteins, enabling biochemical and functional studies. Key characteristics include:
Applications:
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E. coli-produced LDHA is ideal for structural studies due to high purity and cost-effectiveness.
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Glycosylated LDHA from Sf9 cells mimics natural post-translational modifications, enhancing relevance for in vivo studies .
Genetic Mouse Models of LDHA Dysfunction
Conditional KO models and tissue-specific deletions have revealed LDHA’s tissue-dependent roles:
Functional Roles of LDHA in Murine Tissues
LDHA’s isoform-specific activity is critical in diverse physiological and pathological contexts:
Hypoxia and Kidney Injury
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Proximal Tubular Cells (PTCs): Hypoxia induces LDHA (but not LDHB) expression, increasing LDH activity and lactate production .
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Mechanism: LDHA upregulation in murine PTCs under hypoxic conditions aligns with human HK-2 cell responses, suggesting conserved metabolic adaptations .
Neurological Regulation
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Astrocytic LDHA: Deletion in the dorsomedial prefrontal cortex (dmPFC) reduces extracellular lactate, lowering neuronal firing frequencies and inducing depressive-like behaviors .
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Therapeutic Implications: Rescuing LDHA in the dmPFC via viral overexpression reverses depression phenotypes in socially defeated mice .
Cancer Metabolism
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HCC Progression: Ldha deletion in hepatocytes suppresses tumor growth, highlighting LDHA as a therapeutic target for enhancing anti-cancer therapies .
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TCGA Data Correlation: Low LDHA expression in human HCCs correlates with improved survival, reinforcing its role in cancer aggressiveness .
Gene Structure and Expression Patterns
The Ldha gene (NCBI Gene ID: 16828) exhibits complex transcriptional regulation:
Developmental Expression:
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LDHA is low in neonatal testes but surges at postnatal day 21, aligning with spermatogenesis onset .
Metabolic Dependencies and Pathological Links
LDHA’s role in lactate production intersects with critical pathways:
Product Specs
Q&A
Basic Research Questions
What mouse models are most effective for studying LDHA function in neurological disorders?
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Conditional knockout models: Use GFAP-Cre x Ldha-loxp mice to delete LDHA in astrocytes, preserving systemic viability while targeting brain-specific mechanisms .
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AAV-mediated knockdown: Inject AAV9-shLDHA into the dorsomedial prefrontal cortex (dmPFC) to study cell-type-specific effects on neuronal excitability and depressive-like behaviors .
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Validation metrics: Confirm LDHA reduction via Western blot (37.5 kDa band) and measure extracellular L-lactate levels using enzymatic assays .
How do researchers measure LDHA-related behavioral phenotypes in mice?
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Depression models:
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Motor/cognitive assays:
What are standard methods to detect LDHA expression/activity in mouse tissues?
Advanced Research Questions
How do cell-type-specific LDHA deletions resolve contradictory findings in tumorigenesis studies?
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Context-dependent roles:
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Methodological insight: Use lineage-specific Cre drivers (e.g., GFAP-Cre for astrocytes, SMMHC-Cre for smooth muscle) to isolate tissue-specific effects .
What experimental designs address LDHA’s non-cell-autonomous effects on neuronal excitability?
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Dual electrophysiology: Record both virus-infected (GFP+) and neighboring (GFP−) neurons in AAV-LDHA-KD mice to distinguish direct vs. astrocyte-mediated effects .
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Lactate supplementation: Intracerebral L-lactate delivery rescues firing deficits in GFAP-Ldha−/− mice, confirming metabolic crosstalk .
How can researchers reconcile LDHA’s divergent roles in cancer vs. neuropsychiatric models?
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Unified approach: Combine single-cell RNA sequencing (to map LDHA+ cells) and LC-MS metabolomics (to track lactate flux) .
What translational strategies are emerging from LDHA mouse studies?
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Pharmacological targeting: LDHA inhibitors (e.g., GNE-140) tested in glioblastoma models reduce tumor growth by 60% .
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Gene therapy: AAV9-shLDHA decreases RVSP by 35% in hypoxic PH mice, highlighting clinical potential .
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Biomarker pipelines: Correlate plasma lactate levels (↑ in PH ) with PET imaging of brain lactate in depression models .
Methodological Best Practices
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Control for sex differences: Use male mice in PH studies (female hormones confound vascular responses) , but include both sexes in neurobehavioral work .
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AAV optimization: Titrate AAV9-shLDHA to 1×10¹¹ genome copies for smooth muscle targeting vs. 5×10¹⁰ for neuronal delivery .
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Data normalization: Express neuronal firing rates as % baseline (control = 100%) to account for slice-to-slice variability .
Product Science Overview
Lactate Dehydrogenase A (LDHA) is a crucial enzyme involved in the metabolic pathway of anaerobic glycolysis. It catalyzes the reversible conversion of pyruvate to lactate with the concomitant oxidation of NADH to NAD+. This enzyme is predominantly found in skeletal muscle and is part of the lactate dehydrogenase family .
LDHA is a protein-coding gene that encodes the A subunit of the lactate dehydrogenase enzyme. The enzyme is composed of four subunits, forming a tetrameric structure. Each subunit has a molecular weight of approximately 35 kDa, resulting in a total molecular weight of around 140 kDa for the tetrameric enzyme . The enzyme’s active site binds to pyruvate and NADH, facilitating the conversion to lactate and NAD+ under anaerobic conditions .
LDHA is predominantly expressed in muscle tissue, where it plays a vital role in energy production during intense physical activity. The expression of LDHA is hormonally regulated in rodents and is known to be overexpressed during mammary gland tumorigenesis . This overexpression is often associated with the altered glycolytic metabolism observed in cancer cells .
Recombinant LDHA from mice is produced using various expression systems, such as baculovirus. The recombinant protein typically includes a His-tag for purification purposes and corresponds to the amino acids 1-332 of the mouse LDHA sequence . The recombinant enzyme retains its functionality, with a specific activity of over 250 units/mg, defined as the amount of enzyme that converts 1.0 µmole of pyruvate to L-lactate per minute at pH 7.5 at 37°C .
