DYNC1I2 Antibody

What is DYNC1I2 and what cellular functions does it mediate?

DYNC1I2 serves as a non-catalytic accessory component of the cytoplasmic dynein 1 complex involved in linking dynein to cargos and adapter proteins that regulate dynein function. The protein mediates binding of dynein to dynactin via its 150 kDa component (p150-glued) DCTN1, facilitating membrane transport processes involving Golgi apparatus, late endosomes, and lysosomes. Recent research has revealed DYNC1I2's critical role in intracellular retrograde motility of vesicles and organelles along microtubules . Importantly, cytoplasmic dynein 1 intermediate chain 2 acts as a crucial linker within the dynein-dynactin complex essential for proper microtubule-based transport.

What applications are DYNC1I2 antibodies validated for?

DYNC1I2 antibodies have been extensively validated for multiple applications, with different products showing specific reactivity profiles:

This multi-method validation ensures reliability across different experimental designs, allowing researchers to confidently choose appropriate applications based on their specific research questions .

How should I select the appropriate DYNC1I2 antibody for my research?

Selection of the appropriate DYNC1I2 antibody should be based on several key factors:

• Target region specificity: Consider whether targeting specific domains (e.g., C-terminal) is critical for your research. Some antibodies target specific regions like the recombinant fragment within amino acids 100-200 of human DYNC1I2, while others target C-terminal regions .

• Species reactivity: Verify cross-reactivity with your experimental model. Available antibodies show reactivity against human, mouse, and rat DYNC1I2, but reactivity profiles vary between products .

• Application compatibility: Match the antibody to your planned application. While many antibodies work across multiple applications, performance can vary significantly between different techniques .

• Validation depth: Review the validation data available for specific applications and cell/tissue types similar to your experimental system. Comprehensive validation data significantly increases reliability of experimental outcomes .

Look for antibodies with validation in knockdown/knockout systems as these provide the most stringent specificity controls, as evidenced by siRNA experiments showing significant signal reduction in Western blot analyses .

What optimization strategies improve DYNC1I2 detection in immunofluorescence studies?

Optimizing DYNC1I2 detection in immunofluorescence requires careful consideration of fixation, permeabilization, and epitope accessibility:

These optimization strategies have been validated in studies examining DYNC1I2's association with dynactin and its role in dynein activation through protein interactions .

How can I validate DYNC1I2 antibody specificity in my experimental system?

Rigorous validation of DYNC1I2 antibody specificity is essential for generating reliable data. A comprehensive validation approach includes:

• Genetic knockdown/knockout controls: Utilize siRNA-mediated knockdown of DYNC1I2 (as demonstrated in U-2 OS cell experiments with specific siRNA probes) to confirm antibody specificity. Western blot analysis following knockdown should show significant signal reduction .

• Peptide competition assays: Pre-incubation of the antibody with immunizing peptide should abolish specific staining in both Western blot and immunofluorescence applications.

• Recombinant protein controls: Use purified recombinant DYNC1I2 as a positive control in Western blot applications to confirm appropriate molecular weight detection (68-72 kDa) .

• Multiple antibody validation: Compare staining patterns using antibodies targeting different DYNC1I2 epitopes, such as those against the C-terminal region versus those against amino acids 100-200, to confirm consistent localization patterns .

• Cross-species reactivity assessment: If working with model organisms, confirm antibody specificity across species by comparing staining patterns in cells from multiple species where sequence homology is known .

Implementation of these validation approaches has been critical in studies identifying novel dynein activators and characterizing dynein-dynactin interactions .

What experimental approaches can identify novel DYNC1I2 protein interactions?

Several complementary approaches have proven effective for identifying and characterizing novel DYNC1I2 protein interactions:

• BioID proximity labeling: This approach successfully identified DYNC1I2 interactions by fusing BioID to IC2, allowing biotinylation of proximal proteins. Gel filtration analysis confirmed that 51% of BioID-tagged IC2 was incorporated into the dynein complex, validating this approach for discovering physiologically relevant interactions .

• Co-immunoprecipitation (Co-IP): Using validated DYNC1I2 antibodies for immunoprecipitation followed by mass spectrometry analysis has identified key interaction partners. This approach requires careful optimization of lysis conditions (typically using 0.5-4.0 μg antibody for 1.0-3.0 mg protein lysate) .

• Yeast two-hybrid screening: While not directly evidenced in the provided search results, this approach provides complementary data to immunoprecipitation studies for identifying direct protein-protein interactions.

• Proximity ligation assay (PLA): This technique allows visualization of protein interactions in situ with high specificity and sensitivity, enabling detection of transient or weak interactions that might be lost in traditional Co-IP experiments.

These methods led to the discovery that ninein (NIN) and ninein-like (NINL) proteins represent a new family of dynein activators through interactions with DYNC1I2, demonstrating the value of systematic interaction studies .

How are DYNC1I2 antibodies utilized in neurodevelopmental disorder research?

DYNC1I2 antibodies have become essential tools in investigating neurodevelopmental disorders, particularly those involving microcephaly and intellectual disability:

• Mutation characterization: DYNC1I2 antibodies enable functional characterization of disease-associated variants, such as the homozygous splice donor site variant (c.607+1G>A) and missense variant (p.Tyr247Cys) identified in patients with syndromic microcephaly .

• Cellular phenotyping: Immunofluorescence studies using DYNC1I2 antibodies help characterize altered subcellular localization patterns in patient-derived cells harboring DYNC1I2 mutations, revealing mechanisms underlying pathogenesis .

• Protein expression analysis: Western blotting with DYNC1I2 antibodies allows quantification of expression levels in patient samples, critical for understanding haploinsufficiency or dominant-negative effects of disease variants .

• Brain tissue studies: Immunohistochemistry applications using DYNC1I2 antibodies in brain tissue samples allow visualization of expression patterns in regions affected by neurodevelopmental disorders. The recommended protocol includes heat-mediated antigen retrieval with citrate buffer pH 6 before IHC staining .

Research utilizing these approaches has established that bi-allelic variants in DYNC1I2 cause a syndrome characterized by microcephaly, intellectual disability, simplification of cerebral gyration, corpus callosum hypoplasia, and distinctive facial features .

What approaches can assess the functional impact of DYNC1I2 variants?

Assessing the functional consequences of DYNC1I2 variants requires multiple complementary approaches:

• Structural modeling: Molecular modeling using cryo-EM structures of dynein-dynactin complexes with different adaptors can predict structural consequences of missense variants like p.Tyr247Cys. This approach utilizes software like UCSF Chimera to visualize protein structures and predict functional impacts .

• Animal models: Zebrafish models employing CRISPR/Cas9 or morpholino-based knockdown of DYNC1I2 orthologs (dync1i2a and dync1i2b) have been developed to assess phenotypic consequences of DYNC1I2 loss. Analysis includes RT-PCR verification of knockdown efficiency using primers flanking the targeted regions .

• Cellular assays: Evaluating dynein-dependent processes including organelle transport, Golgi organization, and microtubule organization in cells expressing variant DYNC1I2 provides functional readouts of pathogenicity.

• Co-immunoprecipitation studies: Using DYNC1I2 antibodies for immunoprecipitation followed by Western blotting for interaction partners can reveal altered protein-protein interactions resulting from pathogenic variants .

These approaches have collectively demonstrated that pathogenic DYNC1I2 variants disrupt critical functions of the dynein-dynactin complex, particularly affecting neuronal development and migration .

How can I troubleshoot weak or non-specific signals in DYNC1I2 Western blots?

Troubleshooting DYNC1I2 Western blot issues requires systematic optimization of several parameters:

• Antibody concentration: The recommended dilution range for Western blot applications is 1:500-1:1000, but optimal concentration may vary by specific antibody and sample type . For some DYNC1I2 antibodies, 0.4 μg/mL has been established as optimal .

• Sample preparation: DYNC1I2 is a component of large protein complexes that may require specific lysis conditions. Use lysis buffers containing appropriate detergents (e.g., RIPA buffer with protease inhibitors) to ensure complete protein extraction while preserving epitope integrity.

• Loading control selection: When analyzing DYNC1I2 (predicted band size: 71 kDa; observed: 68-72 kDa), select loading controls that do not overlap with this molecular weight range .

• Blocking optimization: BSA-based blocking buffers (3-5%) may provide lower background than milk-based blockers for some DYNC1I2 antibodies.

• Validation strategy: Confirm specificity using siRNA-mediated knockdown, as demonstrated in U-2 OS cells where a significant reduction in signal was observed following transfection with target-specific siRNA probes .

These troubleshooting approaches have proven effective in studies analyzing DYNC1I2 incorporation into the dynein complex and its interactions with dynactin components .

What are the critical controls for DYNC1I2 immunoprecipitation experiments?

Successful DYNC1I2 immunoprecipitation experiments require several essential controls:

• Negative controls: Include isotype-matched irrelevant antibodies and no-antibody controls to identify non-specific binding to beads or other components of the immunoprecipitation system.

• Input control: Always include an input sample (typically 5-10% of the material used for immunoprecipitation) to evaluate immunoprecipitation efficiency and verify the presence of proteins of interest in the starting material.

• Known interaction partners: Include blotting for established DYNC1I2 binding partners (e.g., dynactin components like p150-glued/DCTN1) as positive controls for successful immunoprecipitation of the intact complex .

• Reciprocal immunoprecipitation: When studying novel interactions, perform reciprocal immunoprecipitation with antibodies against the putative binding partner followed by Western blotting for DYNC1I2.

• Antibody amount optimization: Titrate antibody amounts (recommended range: 0.5-4.0 μg for 1.0-3.0 mg of total protein lysate) to identify conditions that maximize specific immunoprecipitation while minimizing non-specific binding .

These controls were instrumental in studies that identified novel dynein activators including ninein (NIN) and ninein-like (NINL) through co-immunoprecipitation with dynein and dynactin complexes .

How can DYNC1I2 antibodies be utilized in advanced imaging technologies?

DYNC1I2 antibodies can be leveraged in cutting-edge imaging applications to provide dynamic insights into cytoplasmic dynein function:

• Super-resolution microscopy: DYNC1I2 antibodies compatible with techniques like STORM, PALM, or STED enable visualization of dynein complex organization at nanometer resolution, revealing previously undetectable structural features.

• Live-cell imaging: While conventional antibodies require cell fixation, emerging technologies like antibody fragments (Fabs) labeled with cell-permeable fluorescent tags enable tracking of DYNC1I2 dynamics in living cells.

• Correlative light and electron microscopy (CLEM): DYNC1I2 antibodies validated for both immunofluorescence and immunogold labeling allow precise localization within cellular ultrastructure, correlating functional data with structural context.

• Expansion microscopy: This technique physically expands samples after DYNC1I2 immunolabeling, enabling super-resolution imaging on conventional microscopes while maintaining the specificity of antibody-based detection.

• Imaging mass cytometry: Conjugating DYNC1I2 antibodies to metal isotopes enables multiplexed protein detection in tissues with spatial resolution, allowing simultaneous visualization of multiple components of the dynein-dynactin complex and associated proteins.

Immunofluorescent analysis using DYNC1I2 antibodies at 4 μg/ml concentration has successfully visualized its distribution in fixed and permeabilized cells, providing a foundation for more advanced imaging applications .

What approaches can detect post-translational modifications of DYNC1I2?

Detecting post-translational modifications (PTMs) of DYNC1I2 requires specialized approaches:

• Modification-specific antibodies: Development of antibodies specifically targeting phosphorylated, ubiquitinated, or otherwise modified forms of DYNC1I2 enables direct detection of these species in complex samples.

• Phosphatase/deubiquitinase treatments: Comparing DYNC1I2 immunoblots before and after treatment with these enzymes reveals shifts in molecular weight or changes in band patterns indicative of specific modifications.

• Mass spectrometry approaches: Immunoprecipitation of DYNC1I2 followed by mass spectrometry analysis allows comprehensive mapping of PTMs and identification of modification sites.

• Phos-tag SDS-PAGE: This technique improves separation of phosphorylated protein species and can be combined with DYNC1I2 immunoblotting to detect phosphorylation events that may not cause significant mobility shifts in conventional SDS-PAGE.

• 2D gel electrophoresis: Separating proteins by isoelectric point before size-based separation can resolve differently modified forms of DYNC1I2 that conventional 1D electrophoresis might miss.

Although the search results do not specifically address PTM detection for DYNC1I2, these approaches represent state-of-the-art methodologies applicable to studying modifications that may regulate dynein complex assembly and function.