DNA unwinding component of the nonhistone chromatin proteins

A subclass of nonhistone chromatin proteins from rat liver, previously shown to exhibit high affinity for DNA, has been fractionated by single-stranded DNA-agarose affinity chromatography. The protein fraction that bound to DNA-agarose in 0.19 M NaCl-buffer and was eluted with 2 M NaCl-buffer is enriched for a protein component of approximately 20,000 daltons and exhibits preferential binding to denatured DNA. This nonhistone protein fraction specific for single strands binds to DNA in a non-species-specific manner, and causes helix-coil transition of synthetic poly[d(A-T)· d(A-T)] at 25 degrees, as indicated by the increase in absorbance of ultraviolet light at 260 nm. The observed hyperchromicity does not result from any nuclease activity in the protein fraction, because addition of Mg+2 results in partial hypochromic shift, and the protein/DNA complex is retained by nitrocellulose filters

DERIVED DEMAND FOR WHEAT BY CLASS

To quantify price responsiveness and economic substitutability among wheat classes, derived demand functions were specified from a normalized quadratic profit function. Own-price and cross-price elasticities were estimated for hard red winter, hard red spring, soft wheat (combined red and white), and durum wheat. In general, soft wheat varieties were less responsive to their own price than were hard wheat varieties. Cross-price elasticities indicate that hard red winter wheat, hard red spring wheat, and soft wheat varieties are economic substitutes. Cross-price elasticities are different from those previously reported, which can have important policy implications.elasticities, normalized quadratic, substitution, Crop Production/Industries, Demand and Price Analysis,