Structural organization of calmodulin genes in the rat genome.
In summary, we present a list of phage clones we have obtained from rat genomic libraries (from lamba SC1 to lambda SC31, lambda WC1 and lambda WC40) together with cDNA clones we have obtained from a rat brain cDNA library (PRCM1,5,3 and 4). pRCM5 corresponds to 4.0 kb mRNA species observed primarily in skeletal muscle. These clones can be classified into three groups. They belong to three bona fide calmodulin genes with five to six exons called CaM I, CaM II and CaM III and four intronless retropseudogenes, one derived from CaM I and three derived from CaM II. We have not obtained retropseudogenes for CaM III so far. These three bona fide genes are transcribed into multiple sized mRNA species in a tissue-specific manner, that is, CaM I is ubiquitous, CaM II is transcribed mainly in brain and CaM III is transcribed primarily in brain and skeletal muscle. Four retropseudogenes do not appear to be transcribed. They are probably relics of inactivated genes. The physiological meanings of multiple calmodulin mRNA species and mechanisms of transcriptional regulation of these three bona fide genes will be the main subjects of our future experiments.
Nojima
H
H
Department of Pharmacology, Jichi Medical School, Lochigi-ken, Japan.
Sokabe
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D015139:Blotting, Southern; D002147:Calmodulin / Q000235:genetics*; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005796:Genes; D015698:Genomic Library; D008969:Molecular Sequence Data; D051381:Rats / Q000235:genetics*; D014158:Transcription, Genetic
D002147:Calmodulin; D004247:DNA