Related Experiment Videos
Cloning and characterization of a cDNA encoding bovine mannan-binding protein
1Department of Food Microbiology, Osaka Prefectural Institute of Public Health, Japan.
Gene
|February 28, 1997
Summary
Researchers identified bovine mannan-binding protein (MBP) through cDNA cloning and protein analysis. This bovine MBP activates complement and is primarily expressed in the liver, distinguishing it from other bovine collectins.
Area of Science:
- Immunology
- Molecular Biology
- Biochemistry
Background:
- Mannan-binding protein (MBP) plays a crucial role in the innate immune system.
- Identifying homologous proteins across species aids in understanding conserved immune functions.
Purpose of the Study:
- To identify and characterize the bovine mannan-binding protein (MBP).
- To investigate the functional properties and expression patterns of bovine MBP.
Main Methods:
- cDNA library screening and sequencing to isolate bovine MBP gene.
- Protein purification using mannan-Sepharose chromatography.
- SDS-PAGE and Western blot analysis for protein identification.
- Complement activation assays (passive hemolysis).
- Northern blot analysis for gene expression.
Main Results:
- Isolation of a 747 bp cDNA encoding a 249 amino acid bovine MBP with a signal peptide.
- Purified 33 kDa bovine MBP protein confirmed by SDS-PAGE and Western blot.
- Bovine MBP demonstrated complement-activating ability.
- A 1.8-kb mRNA transcript for bovine MBP was detected exclusively in the liver.
- Genomic analysis suggests bovine MBP is a homolog of human MBP and similar to rat/mouse MBP-C.
Conclusions:
- The isolated cDNA encodes a bovine serum mannan-binding protein.
- Bovine MBP is a liver-expressed protein with complement activation capabilities.
- Bovine MBP represents a distinct collectin, separate from bovine SP-D, conglutinin, and CL-43.