HDAC7 Antibody

What is HDAC7 and what biological functions does it serve?

HDAC7 is a class IIa histone deacetylase that functions as a lysine deacetylase and scaffolding protein. It plays crucial roles in:

• Removing acetyl groups from lysine residues on histones, leading to chromatin condensation and transcriptional repression

• Regulating gene expression through formation of repressor complexes with transcription factors and co-repressors such as mSin3A, SMRT and N-CoR

• Controlling cellular processes including proliferation, differentiation, and survival in multiple tissue types

• Maintaining vascular integrity during embryogenesis

• Mediating immune cell functions and development, particularly in T-cell selection processes

• Supporting neuronal survival through deacetylase-independent mechanisms

HDAC7 can be localized in both the nucleus and cytoplasm, with its cellular localization being regulated by phosphorylation events in response to various stimuli . Within the nucleus, HDAC7 generally inhibits gene expression by forming repressor complexes with transcription factors and co-regulators, with its enzymatic activity in this compartment relying on binding to HDAC3 .

What types of HDAC7 antibodies are available for research applications?

Researchers have access to various HDAC7 antibody types, each with specific characteristics and applications:

When selecting an antibody, researchers should consider the specific experimental application, species reactivity requirements, and whether the antibody targets the relevant domain or epitope of HDAC7 for their research question .

What are the recommended storage and handling conditions for HDAC7 antibodies?

Proper storage and handling of HDAC7 antibodies are essential for maintaining antibody performance:

• Most HDAC7 antibodies should be stored at -20°C in solutions containing glycerol and/or sodium azide

• Typical storage buffer consists of PBS with 0.02% sodium azide and 50% glycerol at pH 7.3

• Antibodies are generally stable for one year after shipment when properly stored

• Aliquoting may be unnecessary for -20°C storage for some formulations, reducing freeze-thaw cycles

• Some preparations contain 0.1% BSA as a stabilizer

• For applications, specific dilutions are recommended (e.g., IP: 0.5-4.0 μg for 1.0-3.0 mg of total protein lysate)

• Always titrate the antibody in each experimental system to determine optimal concentrations

Following these guidelines will help ensure consistent and reliable results when working with HDAC7 antibodies.

What are the common applications of HDAC7 antibodies in research?

HDAC7 antibodies are versatile tools employed in multiple experimental techniques:

• Western blotting (WB): For detecting HDAC7 protein expression levels (typical dilution: 0.25-0.5 μg/mL)

• Immunoprecipitation (IP): For isolating HDAC7 and its associated protein complexes (recommended amounts: 0.5-4.0 μg antibody for 1.0-3.0 mg of total protein lysate)

• Immunofluorescence (IF)/Immunocytochemistry (ICC): For examining subcellular localization of HDAC7, which shuttles between nucleus and cytoplasm

• Enzyme-linked immunosorbent assay (ELISA): For quantitative detection of HDAC7 protein

• Chromatin immunoprecipitation (ChIP): For identifying genomic regions bound by HDAC7, particularly important given its role in transcriptional regulation

• Flow cytometry: Using conjugated antibodies to quantify HDAC7 in cell populations

These applications enable researchers to comprehensively investigate HDAC7 expression, interactions, and functions in various experimental contexts.

How can researchers validate the specificity of HDAC7 antibodies?

Validating antibody specificity is crucial for producing reliable data:

• Knockdown/knockout controls: Use shRNA (e.g., shHdac7-1, shHdac7-2) or siRNA targeting HDAC7 to confirm signal reduction with the antibody after knockdown

• Multiple antibody approach: Compare results using antibodies recognizing different epitopes of HDAC7 to ensure consistent detection patterns

• Tissue expression patterns: Test antibodies in tissues with established HDAC7 expression (high in thymocytes, vascular endothelium) versus low-expressing tissues

• Peptide competition assays: Pre-incubate the antibody with immunizing peptide (such as HDAC7 fusion protein Ag24396) to confirm signal reduction

• Reactivity testing: Verify antibody performance in species of interest (most HDAC7 antibodies show reactivity with human, with some also detecting mouse/rat HDAC7)

• Molecular weight confirmation: Verify detection at the expected molecular weight (~102-103 kDa for full-length HDAC7)

Implementing these validation strategies will significantly increase confidence in experimental findings using HDAC7 antibodies.

How can HDAC7 antibodies be used to study protein-protein interactions in transcriptional regulation?

HDAC7 functions through multiple protein-protein interactions to regulate gene expression. Researchers can employ several methodological approaches:

• Co-immunoprecipitation (Co-IP):

  • Use HDAC7 antibodies to pull down HDAC7 complexes from nuclear or cytoplasmic fractions

  • Probe for interaction partners including MEF2 family proteins, HDAC3, SMRT, N-CoR, and PLZF

  • Consider native vs. cross-linking conditions to preserve transient or weaker interactions

  • Example protocol: Use 0.5-4.0 μg HDAC7 antibody for IP from 1.0-3.0 mg of total protein lysate

• Sequential ChIP (ChIP-re-ChIP):

  • First perform ChIP with HDAC7 antibody to isolate HDAC7-bound chromatin

  • Re-immunoprecipitate with antibodies against suspected interaction partners

  • This identifies genomic regions co-occupied by HDAC7 and its binding partners

  • Particularly useful for studying HDAC7's interactions with MEF2 transcription factors at specific promoters

• Proximity Ligation Assay (PLA):

  • Combine HDAC7 antibody with antibodies against potential interaction partners

  • Visualize and quantify protein interactions with subcellular resolution

  • Especially valuable for studying nuclear vs. cytoplasmic interactions of HDAC7

Research findings demonstrate that HDAC7 interacts with MEF2 family transcription factors through a conserved binding motif in its N-terminal region, enabling repression of MEF2-dependent genes involved in processes like muscle differentiation and vascular integrity . Additionally, HDAC7's enzymatic activity in the nucleus relies on binding to HDAC3, whereas cytoplasmic HDAC7 was found to be enzymatically inactive as it does not bind to this class I HDAC .

What methodological approaches can be used to study HDAC7's role in T-cell development and selection?

HDAC7 plays critical roles in T-cell development, particularly in thymic selection processes. Advanced methodological approaches include:

• Gene expression profiling after HDAC7 manipulation:

  • Express HDAC7 mutant proteins (constitutively nuclear or lacking deacetylase domain) in T-cell lines

  • Use DNA microarrays to identify transcriptional targets of HDAC7 in T cells

  • Compare gene expression changes to profiles associated with positive and negative thymic selection

  • Research has revealed that HDAC7 regulates genes differentially expressed during both positive and negative thymic selection

• ChIP-seq to map HDAC7 binding sites:

  • Use HDAC7 antibodies for genome-wide chromatin immunoprecipitation in thymocytes

  • Identify HDAC7 binding sites at promoters of genes involved in T-cell development

  • Research has shown HDAC7 binds to the promoter of Nur77, an orphan steroid receptor important in negative selection

• Phosphorylation-specific studies:

  • Use antibodies that distinguish between phosphorylated and non-phosphorylated HDAC7

  • Track HDAC7 phosphorylation status and subcellular localization after T-cell receptor engagement

  • The release of HDAC7 from the Nur77 promoter is coupled to antigen receptor engagement by the activation of PKD

• Transgenic/knockout models with immunophenotyping:

  • Express phosphorylation-deficient, constitutively nuclear HDAC7 in thymus (HDAC7-ΔP)

  • Examine effects on T-cell development, selection, and autoimmunity

  • Research found that HDAC7-ΔP expression blocks negative selection and diverts Vα14/Jα18 TCR transgenic thymocytes into a conventional T-cell-like lineage

Research findings demonstrate that HDAC7 controls the thymic effector programming of Natural Killer T (NKT) cells, and interference with this function contributes to tissue-specific autoimmunity . HDAC7 binds PLZF and modulates PLZF-dependent transcription, potentially explaining its role in NKT cell development .

What approaches should be used to study HDAC7's role in cancer progression and therapeutic resistance?

HDAC7 has been implicated in various cancers. Sophisticated methodological approaches include:

• Clinical sample analysis:

  • Use immunohistochemistry with HDAC7 antibodies on tissue microarrays

  • Correlate HDAC7 expression/localization with patient outcomes

  • Published findings link HDAC7 to ovarian cancer, glioblastoma, and non-small cell lung cancer (NSCLC)

• Mechanistic pathway studies:

  • Combine HDAC7 antibody-based detection with signaling pathway analysis

  • For example, research has shown HDAC7 promotes NSCLC proliferation and metastasis via stabilization by deubiquitinase USP10 and activation of β-catenin-FGF18 pathway

  • In glioblastoma, FBXW7 has been shown to induce apoptosis by regulating HDAC7

• Therapeutic resistance mechanisms:

  • Use HDAC7 antibodies to study its role in resistance to therapeutic antibodies

  • Research found that HDAC7 is an actionable driver of therapeutic antibody resistance by modulating phagocytic responses in chronic lymphocytic leukemia (CLL)

  • Class IIa-selective HDAC inhibitor (TMP195) enhances phagocytic responses to antibody-opsonised CLL cells within 30 minutes of treatment

• HDAC7 knockdown/inhibition in cancer models:

  • Combine genetic approaches (shRNA, CRISPR) with pharmacological inhibition

  • Track consequences using HDAC7 antibodies for protein detection

  • Research showed HDAC7 knockdown induces hyperacetylation and hyperphosphorylation of Bruton's tyrosine kinase (BTK), and BTK inhibitors abrogated the enhanced response to HDAC7 inhibition

These methodologies allow researchers to elucidate HDAC7's complex roles in cancer biology and potentially identify novel therapeutic targets.

How can researchers investigate HDAC7's neuroprotective functions using HDAC7 antibodies?

HDAC7 has been identified as a neuroprotective protein acting through deacetylase-independent mechanisms. Advanced research approaches include:

• Expression analysis in neurodegeneration models:

  • Use HDAC7 antibodies to track expression in various neuronal stress/disease models

  • Research has shown reduced HDAC7 expression in cerebellar granule neurons (CGNs) undergoing apoptosis, in cortical neurons treated with homocysteic acid, and in the striatum of R6/2 transgenic mice (Huntington's disease model)

• Structure-function analysis:

  • Express HDAC7 truncation mutants lacking specific domains

  • Use antibodies to confirm expression and study their neuroprotective effects

  • Research using HDAC7(1–519) and HDAC7(514–953) constructs demonstrated that HDAC7-mediated neuroprotection does not require its catalytic domain

• Transcriptional regulation studies:

  • Use ChIP with HDAC7 antibodies to study its association with promoters of genes involved in neuronal survival/death

  • Research has shown HDAC7 directly associates with the c-jun gene promoter, inhibiting its expression, which is essential for neuronal survival

• Signaling pathway analysis:

  • Combine HDAC7 antibody detection with inhibitors of various signaling pathways

  • Research tested inhibitors of PI3K-Akt, Raf-MEK-ERK, PKA, PKC, and Ca2+/calmodulin-dependent protein kinase pathways, finding they failed to reduce neuroprotection by HDAC7

These methodological approaches revealed that HDAC7 is a neuroprotective protein acting through a mechanism independent of its deacetylase activity, primarily involving the inhibition of c-jun expression, a transcription factor that plays a pivotal role in promoting neuronal death .

What methodologies can researchers employ to study HDAC7-derived peptides in vascular biology?

Recent research has identified bioactive peptides derived from HDAC7, particularly a 7-amino acid peptide that promotes vascular regeneration. Advanced methodological approaches include:

• Custom antibody development:

  • Generate antibodies specifically targeting the 7-amino-acid (7A) peptide

  • Research used a synthetic peptide (MEKK1 phosphopeptide: VVESSEKAYSC) to raise specific anti-7A antibodies

• Peptide blocking experiments:

  • Pre-incubate anti-7A antibody with 7A peptide (1 μg Ab:1 μg peptide) overnight

  • Compare with non-blocked antibody to confirm specificity

• Signal transduction pathway analysis:

  • Use phospho-specific antibodies to study the role of 7A peptide as a phosphate group carrier

  • Research identified a novel signal transduction pathway (MEKK1-7A-14-3-3γ) downstream of vascular endothelial growth factor

• Cell-specific effects on progenitor cells:

  • Isolate Sca1+-vascular progenitor cells (VPCs) from arterial vessels

  • Study the effects of 7A peptide on VPC activation and vascular remodeling

  • Culture VPCs in stem cell medium (DMEM supplemented with leukemia inhibitory factor and FBS)

These methodologies revealed that a short open reading frame (sORF) within the 5′-terminal noncoding area of Hdac7 mRNA can be translated into a functional 7-amino-acid peptide that acts as a phosphate group carrier in a novel signal transduction pathway involved in vascular remodeling and angiogenesis .

How should researchers approach studying HDAC7's role in tissue-specific autoimmunity?

HDAC7 has been implicated in tissue-specific autoimmunity, particularly affecting the gastrointestinal/hepatobiliary compartment. Advanced methodological approaches include:

• Transgenic mouse models:

  • Express phosphorylation-deficient, constitutively nuclear HDAC7 (HDAC7-ΔP) in the thymus

  • Use HDAC7 antibodies to confirm expression and study effects on T-cell development

  • Research found that HDAC7-ΔP expression blocks negative selection and causes lethal autoimmunity

• NKT cell development analysis:

  • Use flow cytometry with HDAC7 antibodies to study NKT cell populations

  • Investigate the effects of HDAC7 manipulation on NKT cell development and function

  • Research demonstrated that HDAC7 controls the thymic effector programming of Natural Killer T (NKT) cells

• Protein-protein interaction studies:

  • Immunoprecipitate HDAC7 to study its interaction with PLZF

  • Investigate how HDAC7 modulates PLZF-dependent transcription

  • Research found that HDAC7 binds PLZF and modulates PLZF-dependent transcription

• Autoantibody profiling:

  • Assess autoantibody production in models with altered HDAC7 function

  • Correlate with tissue-specific autoimmune manifestations

  • Research observed autoantibodies to a comprehensive array of tissue antigens, but tissue destruction occurred almost exclusively in the gastrointestinal/hepatobiliary compartment

These approaches revealed that HDAC7 has a key role in regulating the innate effector programming of iNKT cells, partly through direct modulation of PLZF transcriptional activity. Both gain and loss of HDAC7 function in thymocytes resulted in aberrant effector programming of T cells, leading to abnormalities in peripheral populations and tissue-specific autoimmunity .