Recombinant Tetraodon fluviatilis SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily B member 1 (smarcb1)
Description
Overview of SMARCB1 Homologs
SMARCB1 is a conserved subunit of the SWI/SNF (BAF) chromatin remodeling complex, critical for transcriptional regulation, DNA repair, and tumor suppression. While human SMARCB1 is well-characterized (see Table 1), homologs in other species, including Tetraodon fluviatilis (green spotted pufferfish), remain understudied.
Table 1: Key Features of SMARCB1 Across Species
| Species | Gene ID | Protein Length | Key Functions | Disease Associations |
|---|---|---|---|---|
| Homo sapiens | SMARCB1 | 385 aa | Chromatin remodeling, tumor suppression | Rhabdoid tumors, schwannomas |
| Mus musculus | Smarcb1 | 385 aa | Embryonic development, hematopoiesis | Embryonic lethality (knockout) |
| Danio rerio | smarcb1 | 384 aa | Neural crest development | Not reported |
| Tetraodon fluviatilis | Unannotated | ~380–390 aa (predicted) | Hypothesized chromatin regulation | No data available |
Recombinant SMARCB1: General Principles
Recombinant SMARCB1 refers to the protein produced in vitro using heterologous expression systems (e.g., E. coli, insect cells). Key applications include:
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Functional studies: Investigating chromatin remodeling mechanisms.
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Structural analysis: Resolving 3D architecture of SWI/SNF complexes.
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Therapeutic screening: Targeting SMARCB1-deficient cancers.
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Human SMARCB1 requires co-expression with other BAF subunits (e.g., SMARCA4, SMARCC1) for stability .
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Loss of SMARCB1 disrupts enhancer regulation and promotes oncogenic gene expression .
3.1. Comparative Evolutionary Studies
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Sequence alignment: Identify conserved domains (e.g., RPT1/RPT2 repeats) critical for protein interactions .
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Functional divergence: Assess differences in chromatin targeting between aquatic and mammalian homologs.
3.2. Toxicology and Environmental Adaptation
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T. fluviatilis is a model for studying evolutionary adaptations to toxins. Recombinant SMARCB1 could clarify its role in detoxification pathways.
Challenges and Knowledge Gaps
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Genomic annotation: T. fluviatilis SMARCB1 remains unannotated in major databases (NCBI, Ensembl).
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Expression optimization: Codon usage bias in pufferfish genes may necessitate codon-harmonized expression systems.
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Functional validation: No assays (e.g., chromatin accessibility, tumor suppression) have been reported.
Future Directions
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Genome mining: Query the T. fluviatilis genome (NCBI: GCA_901000725.2) to identify SMARCB1 homologs.
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Phylogenetic analysis: Compare with zebrafish (Danio rerio) and human SMARCB1 to infer conserved motifs.
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Collaborative studies: Partner with marine biology labs to explore SMARCB1’s role in pufferfish-specific traits (e.g., tetrodotoxin resistance).
