Cell growth was promoted by 0.1 mu M brassinolide (BL) and inhibited by 5 mu M brassinazole (Brz). Analysis of BR-regulated proteins in nuclear-enriched fractions was carried out using two-dimensional polyacrylamide gel electrophoresis with
a special fluorescent dye. Proteins of interest were identified by correlating normalized spot volume of proteins on the gels with cellular BR level BAY 57-1293 in vivo (Brz-treated cells, extremely low level of BRs; control cells, normal level of BRs; BL-treated cells, high level of BRs). A number of BR-responsive proteins were detected and some of these proteins were identified by nano-liquid chromatography-tandem mass spectrometry after enzymatic digestion. Fluctuations in eight identified nuclear proteins in BL-treated cells were investigated in the first 12 h of treatment. Three nuclear BR-responsive proteins, Nucleosome Assembly
Protein (NAP) 1;1, Band 7 Family Protein, and Vernalization Independence 3, significantly decreased during this time. Meanwhile, NAP1:2, S-Adenosylmethionine Synthetase 2, and 60S Ribosomal Protein L14 increased markedly over time. Since some of these proteins are reportedly related to chromosome remodeling, cell growth induced by BL may involve chromatin remodeling. Interestingly, NAP1:2 was found to be post-translationally modified in response to cellular BR levels. Our study of quantitative protein changes in the nucleus provides valuable GS-4997 cell line insight into BR-induced cellular and physiological responses. (C) 2011 Elsevier Masson SAS. All rights reserved.”
“Yttrium nitride (YN) is a promising semiconductor for use in metal/semiconductor superlattices for thermoelectric applications. We determine its electronic structure, vibrational spectrum, and thermal properties using first-principles density functional theory (DFT) based simulations with a generalized gradient approximation (GGA) of the exchange correlation LGK-974 clinical trial energy. We employ GGA+U and GW approximations in our calculations to (a) improve the accuracy of the
calculation of bandgaps and (b) determine specific features of its electronic structure relevant to transport properties, such as transverse (m(t)*) and longitudinal (m(1)*) conduction band effective mass. To evaluate consequences of forming alloys of YN with other materials to its electronic properties, we have determined the volume deformation potentials. Our results for phonons show a large longitudinal optical (LO) and transverse optical (TO) splitting at the Gamma point in the vibrational spectrum with a gap of 325 cm(-1) arising from long-range dipole-dipole interactions. We estimate temperature dependent lattice specific heat and lattice thermal conductivity based on Boltzmann transport theory to assess YN’s potential for thermoelectric applications. (C) 2011 American Institute of Physics. [doi:10.1063/1.