Article

Molecular cloning and RNA expression of a novel Drosophila calpain, Calpain C.

Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, P.O. Box 7, Budapest H-1518, Hungary.
Biochemical and Biophysical Research Communications (impact factor: 2.48). 04/2003; 303(1):343-9. pp.343-9
Source: PubMed

ABSTRACT The calpains are Ca(2+)-activated cysteine proteases whose biochemical properties have been extensively characterized in vitro. Less is known, however, about the physiological role of calpains. In this respect, Drosophila melanogaster is a useful experimental organism to study calpain activity and regulation in vivo. The sequencing of the fly genome has been recently completed and a novel calpain homologue has been identified in the CG3692 gene product. We embarked on the cloning and characterization of this putative novel calpain. We demonstrate that the actual calpain is different from the predicted protein and we provide experimental evidence for the correction of the genomic annotation. This novel protein, Calpain C, must be catalytically inactive, having mutated active site residues but is otherwise structurally similar to the other known fly calpains. Moreover, we analysed Calpain C RNA expression during Drosophila development by RT-PCR and RNA in situ hybridization, which revealed strong expression in the salivary glands.

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    Sen Zhao, Zhe Liang, Viktor Demko, Rob Wilson, Wenche Johansen, Odd-Arne Olsen, Kamran Shalchian-Tabrizi
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    Peter Friedrich
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    Biochemical and Biophysical Research Communications 11/2004; 323(4):1131-3. · 2.48 Impact Factor
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    Article: The calpain-system of Drosophila melanogaster: coming of age.
    Peter Friedrich, Peter Tompa, Attila Farkas
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    ABSTRACT: Drosophila melanogaster is one of the most popular and powerful model organisms that help our understanding of mammalian (human) life processes at the molecular level. Calpains are Ca(2+)-activated cytoplasmic proteases thought to play multiple roles in intracellular signal processing by limited proteolysis of target substrate proteins, thereby changing their function. The calpain superfamily consists of 14 genes in mammals, but only 4 genes in Drosophila. One may assume that the calpain system, i.e. recognizing calpain-dependent life processes and identifying the substrates cleaved while exerting their functions, would prove easier to solve in Drosophila than in mammals. Recently, major progress has been made in characterizing Drosophila Calpain A, Calpain B and Calpain C. The fourth member, Calpain D (or SOL), was analyzed earlier. At this juncture, it seems justifiable to summarize our knowledge about the Drosophila enzymes, in comparison to the ubiquitous mammalian ones, as regards structure-function relations, mode of activation by Ca(2+) and other factors, inhibition, potential targeting, expression pattern in vivo, etc. Equipped with all this information, we may now embark on the genetic modification of family members, interpreting mutant phenotypes in terms of the cell biology of calpains.
    BioEssays 11/2004; 26(10):1088-96. · 4.95 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

actual calpain
 
Calpain C
 
calpains
 
CG3692 gene product
 
correction
 
Drosophila development
 
experimental evidence
 
genomic annotation
 
mutated active site residues
 
novel calpain homologue
 
novel protein
 
physiological role
 
predicted protein
 
putative novel calpain
 
revealed strong expression
 
RNA
 
salivary glands
 
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vitro