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Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
Multiple calmodulin mRNA species are derived from two distinct genes
Molecular and Cellular Biology
|May 1, 1987
Summary
Researchers identified two functional calmodulin genes (CaMI and CaMII) in rats, alongside two pseudogenes. These genes generate distinct calmodulin mRNA species, with CaMI expressed broadly and CaMII primarily in the brain.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Calmodulin (CaM) is a crucial calcium-binding protein involved in numerous cellular processes.
- Previous observations indicated the existence of multiple calmodulin mRNA species in rat tissues.
Purpose of the Study:
- To determine the number of expressed genes encoding calmodulin in the rat genome.
- To characterize the genomic organization and expression patterns of calmodulin genes.
Main Methods:
- cDNA cloning and sequencing from a rat brain library.
- Genomic Southern hybridization.
- Cloning and sequencing of calmodulin-related genes from genomic libraries.
- Northern blotting and S1 nuclease mapping to analyze mRNA expression.
Main Results:
- Two distinct calmodulin cDNAs (pRCM1 and pRCM3) were identified, originating from two functional genes, CaMI and CaMII.
- Genomic analysis revealed two additional calmodulin-related genes, identified as processed pseudogenes (lambda SC9 and lambda SC8).
- CaMI gene is expressed in liver, muscle, and brain, producing 1.7 and 4 kb mRNA species.
- CaMII gene is primarily expressed in the brain, producing a 1.4 kb mRNA species.
Conclusions:
- The rat genome contains at least two functional calmodulin genes (CaMI and CaMII) and two processed pseudogenes.
- Differential expression and alternative splicing contribute to the diversity of calmodulin mRNA species observed in rat tissues.
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