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L S Minamide

Publications and source records attributed to L S Minamide.

4 recordsLinked to original sources

Nucleotide sequence and expression of a cDNA encoding chick brain actin depolymerizing factor.

Chick brain actin depolymerizing factor (ADF) is a 19-kDa protein that severs actin filaments and binds actin monomers. We have obtained a cDNA encoding ADF by screening a chick embryo lambda gt11 cDNA library with both a rabbit anti-ADF antiserum and two oligonucleotide probes. Several non-full-length clones of 636 bases and one full-length clone of 1886 bases were isolated and sequenced. The full-length cDNA encodes a protein of 165 amino acids with a calculated molecular weight of 18,520. The deduced amino acid sequence shows 73% identity with the porcine brain actin binding protein cofilin. The coding region of the ADF cDNA has been placed in an expression vector, and the resulting protein shows immunoreactivity with an anti-ADF antiserum but not with an anti-cofilin antibody. The expressed ADF has been purified and has an actin depolymerizing activity identical with that of brain ADF. Like cofilin, ADF contains a sequence similar to the nuclear transport signal sequence of the SV40 large T antigen and a calcium/calmodulin-dependent protein kinase II phosphorylation consensus sequence. Northern blots of both embryonic chick brain and muscle RNA revealed two ADF mRNAs of length 2.1 and 0.9 kilobases. Southern blots suggest that the ADF gene is present in a single copy within the chicken genome. ADF contains regions of homology with other actin binding proteins including tropomyosin, gelsolin, and depactin.

Actin Depolymerizing Factors

A filter paper dye-binding assay for quantitative determination of protein without interference from reducing agents or detergents.

A method is described for quantitation of protein in the presence of reducing agents, detergents, and other substances which often interfere with assays of protein in solution. The proteins are applied to Whatman No. 1 filter paper, air-dried, washed with methanol, and then stained with Coomassie brilliant blue G. Following destaining, the paper is air-dried and the protein-bound dye is extracted. Sample absorbance measurements are made in a 96-well plate using an automated microplate reader (600-405 nm) or in a cuvette at 610 nm. This filter paper assay is useful for determining 100 ng to 20 micrograms of protein in the presence of ammonium sulfate, urea, thiol-reducing agents, amino acids, DNA, ionic and nonionic detergents, and acid or base.

Animals