CRYM Human
Description
Domain Architecture
CRYM forms a stable homodimer with two distinct domains:
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Dimerization Domain (Residues 2–112, 195–311):
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NADPH-Binding Domain (Residues 113–294):
| Domain | Key Features | Functional Role |
|---|---|---|
| Dimerization | Hydrophobic interface, β-sheet core | Stabilizes dimer formation |
| NADPH-Binding | Rossmann fold, cofactor specificity | Binds NADPH for enzymatic activity |
Conformational Variability
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Loop Arg83–His92 adopts distinct conformations in dimer subunits.
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Peptide bond Val89–Pro90 exhibits trans-configuration in one monomer and cis-configuration in the other, suggesting dynamic flexibility .
Thyroid Hormone Binding and Regulation
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Binds 3,5,3′-triiodo-L-thyronine (T₃) and regulates gene expression in nuclei.
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T₃ acts as a nanomolar inhibitor, modulating enzymatic activity .
Enzymatic Activity
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Ketimine Reductase: Reduces imine bonds in substrates like aminoethylcysteine ketimine (AECK) at pH 5.0 and 1-piperideine-2-carboxylate at pH 7.2 .
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Cofactor Preference: Utilizes NADPH or NADH, distinguishing it from bacterial homologs (e.g., ornithine cyclodeaminase, which uses NAD+) .
Synaptic Modulation
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Astrocyte-Mediated Neurotransmission:
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Crym-positive astrocytes regulate glutamate/GABA release from orbitofrontal cortex (OFC)–striatum projections.
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Knockout (Crym KO) mice exhibit increased excitatory/inhibitory (E/I) ratios, leading to perseverative behaviors (e.g., repetitive actions) .
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Therapeutic Target: Presynaptic inhibitory chemogenetics restore synaptic balance in Crym KO models .
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Tissue Expression and Localization
Nonsyndromic Deafness (DFNA40)
Neuropsychiatric Disorders
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Downregulation in HD and OCD:
| Disease | CRYM Mutation | Phenotype | Source |
|---|---|---|---|
| DFNA40 | K314T/X315Y | Progressive sensorineural deafness | |
| Huntington’s Disease (HD) | Downregulation | Perseveration, synaptic E/I imbalance |
Recombinant Protein Production
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Expression Systems: E. coli yields non-glycosylated CRYM (35.9 kDa) with His-tag for purification .
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Purity: >95% via SDS-PAGE; lyophilized in Tris/NaCl buffer .
Therapeutic Strategies
Product Specs
Recombinant human CRYM, expressed in E. coli bacteria, is a single polypeptide chain devoid of any glycosylation modifications. It comprises 334 amino acids, with the first 314 representing the CRYM protein and an additional 20 amino acids forming a His-Tag at the N-terminus. The protein has a molecular weight of 35.9 kDa and is purified using proprietary chromatographic methods.
The CYRM solution has a concentration of 1mg/ml and is prepared in a buffer containing 20mM Tris-HCl (pH 8.0), 1mM DTT, and 10% glycerol.
While CRYM remains stable for up to one week at 4°C, it is recommended to store it below -18°C for optimal long-term preservation. Adding a carrier protein like HSA or BSA (0.1%) is advisable for prolonged storage. Repeated freezing and thawing should be avoided.
MGSSHHHHHH SSGLVPRGSH MSRVPAFLSA AEVEEHLRSS SLLIPPLETA LANFSSGPEG GVMQPVRTVV PVTKHRGYLG VMPAYSAAED ALTTKLVTFY EDRGITSVVP SHQATVLLFE PSNGTLLAVM DGNVITAKRT AAVSAIATKF LKPPSSEVLC ILGAGVQAYS HYEIFTEQFS FKEVRIWNRT KENAEKFADT VQGEVRVCSS VQEAVAGADV IITVTLATEP ILFGEWVKPG AHINAVGASR PDWRELDDEL MKEAVLYVDS QEAALKESGD VLLSGAEIFA ELGEVIKGVK PAHCEKTTVF KSLGMAVEDT VAAKLIYDSW SSGK
Q&A
A:
To study the impact of interventions on human resilience, you can use a true experimental design. This involves randomly assigning participants to either an experimental group (receiving the intervention) or a control group (receiving no intervention or "treatment as usual"). Both groups should undergo pre- and post-intervention assessments to measure changes in resilience. Ensure that both groups are as similar as possible in terms of demographics and other relevant factors to control for extraneous variables .
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When analyzing data that contradicts previous studies, consider the following steps:
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Re-evaluate Methodology: Check if the study design, sample size, or data collection methods differ significantly from previous studies.
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Contextual Factors: Consider any contextual factors (e.g., cultural, environmental) that might influence the results.
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Statistical Analysis: Use robust statistical methods to account for potential biases or outliers.
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Literature Review: Conduct a thorough review of existing literature to identify any patterns or inconsistencies that could explain the contradictions .
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To adapt resilience measures for diverse populations, consider the following:
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Cultural Sensitivity: Ensure that the measure is culturally relevant and sensitive to the specific population being studied.
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Item Adaptation: Modify items in the measure if necessary to better fit the context of the population, though this may require re-validation .
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Pilot Testing: Conduct pilot tests with a small sample from the target population to ensure the measure is understood and effective.
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For longitudinal studies on resilience:
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Repeated Measures: Use repeated measures to assess changes in resilience over time.
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Control Groups: Include control groups to compare changes in resilience between intervention and non-intervention groups.
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Data Management: Ensure robust data management practices to track participant retention and handle missing data.
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Statistical Models: Use appropriate statistical models (e.g., mixed-effects models) to analyze longitudinal data .
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To combine qualitative and quantitative methods:
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Triangulation: Use qualitative data to provide depth and context to quantitative findings, enhancing validity through triangulation.
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Mixed-Methods Design: Employ a mixed-methods design where qualitative and quantitative data are collected and analyzed in an integrated manner.
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Sampling Strategy: Ensure that the sampling strategy aligns with both qualitative and quantitative objectives .
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To ensure reliability and validity in applied research:
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Pilot Testing: Conduct pilot tests to refine measures and ensure they are reliable and valid in the specific context.
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Data Quality Control: Implement rigorous data quality control measures during data collection.
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Replicability: While exact replicability may be challenging in dynamic environments, strive to eliminate biases and increase sample size to enhance reliability .
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When conducting studies on human resilience, consider the following ethical aspects:
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Informed Consent: Ensure participants provide informed consent, understanding the purpose and potential impacts of the study.
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Confidentiality: Maintain participant confidentiality and data privacy.
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Beneficence: Ensure that the study benefits participants or contributes significantly to knowledge without causing harm .
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To maximize the impact of resilience study findings:
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Peer-Reviewed Journals: Publish in reputable, peer-reviewed journals to ensure rigorous review and validation.
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Clear Communication: Present findings clearly, using accessible language to facilitate understanding by diverse audiences.
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Dissemination Strategies: Use various dissemination strategies (e.g., conferences, policy briefs) to reach different stakeholders .
Product Science Overview
Crystallins are divided into two main classes: taxon-specific and ubiquitous. Crystallin, Mu falls under the taxon-specific category. The gene encoding Crystallin, Mu is known as CRYM and is located on chromosome 16p13.11 in humans . This gene encodes a protein that is expressed in various tissues, including neural tissue, muscle, and kidney .
The recombinant form of Crystallin, Mu is typically produced in Escherichia coli (E. coli) and includes an N-terminal His-tag for purification purposes . The protein consists of 314 amino acids and has a molecular weight of approximately 35.9 kDa . The high purity of the recombinant protein (>95%) is confirmed through SDS-PAGE analysis .
Crystallin, Mu is also known as ketimine reductase or NADP-regulated thyroid-hormone-binding protein (THBP) . It plays a crucial role in the reduction of imine bonds in brain substrates, which may include cystathionine ketimine (CysK) and lanthionine ketimine (LK) . Additionally, it binds thyroid hormone, which acts as a strong reversible inhibitor . This binding is presumed to regulate the free intracellular concentration of triiodothyronine and its access to nuclear receptors .
