Sequence of an avian non-muscle caldesmon.
We have sequenced a cloned cDNA from a chicken gizzard library which encodes a short version of caldesmon with the properties expected for the non-muscle protein. The predicted protein is 524 amino acids long with a molecular mass of 60,174 daltons. Expression in bacteria produces a protein with an apparent molecular weight on SDS gels of 75-77,000, that comigrates with human platelet caldesmon. The expressed protein binds to F-actin and is retained on calmodulin-Sepharose in the presence, but not absence of Ca2+. This non-muscle caldesmon isoform is identical to the smooth muscle protein at the N- and C-terminal ends, but is missing 232 amino acids from the centre. This central segment is thought to be helical, suggesting that non-muscle caldesmon is approximately 35 nm shorter, about 40 nm overall length, than smooth muscle caldesmon.
Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030.
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J
Bryan
R
R
Lee
D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001717:Birds / Q000235:genetics*; D002118:Calcium / Q000378:metabolism; D002148:Calmodulin-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010957:Plasmids
D000199:Actins; D002148:Calmodulin-Binding Proteins; D002118:Calcium