Recombinant Saccharomyces cerevisiae Lariat debranching enzyme (DBR1)
Description
Biochemical Properties
DBR1 exhibits high catalytic efficiency, with a turnover rate (kcat) of 5.6 sec⁻¹ when expressed in E. coli . Its activity is inhibited by chelating agents like EDTA and deferoxamine (DFO), which strip essential metal cofactors .
Catalytic Specificity
Applications in Research
Recombinant DBR1 has been instrumental in studying RNA splicing defects and retroelement replication. Its depletion in human cells increases intron retention and exon skipping , while its inhibition disrupts retroviral replication (e.g., HIV) .
Experimental Uses
4.1. Metal Cofactor Dynamics
DBR1 requires Fe²⁺ and Zn²⁺ for catalysis, with Fe²⁺ primarily localized in the β-pocket and Zn²⁺ in the α-pocket . Anaerobic conditions enhance Fe²⁺-dependent activity but suppress Zn²⁺-mediated catalysis .
4.2. Cross-Species Complementation
The human hDBR1 cDNA complements the intron accumulation phenotype of S. cerevisiae dbr1 mutants, demonstrating functional conservation . This highlights DBR1’s conserved role in RNA metabolism across eukaryotes.
4.3. Spliceosome Recycling
DBR1 depletion prolongs spliceosome association with excised lariats, delaying spliceosome recycling and promoting exon skipping . This underscores its role in maintaining splicing fidelity.
Product Specs
Target Background
KEGG: sce:YKL149C
STRING: 4932.YKL149C
