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The functional and structural significance of the intrasubunit disulfide bond in copper-zinc superoxide dismutase (SOD1) was studied by characterizing mutant forms of human SOD1 (hSOD) and yeast SOD1 lacking the disulfide bond. We determined x-ray crystal structures of metal-bound and metal-deficient hC57S SOD1. C57S hSOD1 isolated from yeast contained four zinc ions per protein dimer and was structurally very similar to wild type. The addition of copper to this four-zinc protein gave properly reconstituted 2Cu,2Zn C57S hSOD, and its spectroscopic properties indicated that the coordination geometry of the copper was remarkably similar to that of holo wild type hSOD1. In contrast, the addition of copper and zinc ions to apo C57S human SOD1 failed to give proper reconstitution. Using pulse radiolysis, we determined SOD activities of yeast and human SOD1s lacking disulfide bonds and found that they were enzymatically active at ∼10% of the wild type rate. These results are contrary to earlier reports that the intrasubunit disulfide bonds in SOD1 are essential for SOD activity. Kinetic studies revealed further that the yeast mutant SOD1 had less ionic attraction for superoxide, possibly explaining the lower rates. Saccharomyces cerevisiae cells lacking the sod1 gene do not grow aerobically in the absence of lysine, but expression of C57S SOD1 increased growth to 30-50% of the growth of cells expressing wild type SOD1, supporting that C57S SOD1 retained a significant amount of activity.

The RNA-binding protein EWS is a multifunctional protein with roles in the regulation of transcription and RNA splicing. It is one of the FET (FUS, EWS and TAF15) family of RNA binding proteins that contain an intrinsically disordered, low-complexity N-terminal domain. The FET family proteins are prone to chromosomal translocations, often fusing their low-complexity domain with a transcription factor derived DNA-binding domain, that are oncogenic drivers in several leukemias and sarcomas. The fusion protein disrupts the normal function of cells through non-canonical DNA binding and alteration of normal transcriptional programs. However, the exact mechanism for how the intrinsically disordered domain contributes to aberrant DNA binding and abnormal transcription is unknown. The purification and 1H, 13C, and 15N backbone resonance assignments of the amino terminal domain comprising 264 residues of EWS is described. This segment is common to all known EWS-fusions that are the hallmark of the pediatric cancer Ewing sarcoma. This domain is intrinsically disordered and features significant sequence degeneracy resulting in spectra with poor chemical shift dispersion. To alleviate this problem, the domain was divided into three overlapping fragments, reducing the complexity of the spectra and enabling almost complete backbone resonance assignment of the full domain. These solution NMR chemical shift assignments represent the first steps towards understanding, at atomic resolution, how the low-complexity domain of EWS contributes to the aberrant functions of its oncogenic fusion proteins. [ABSTRACT FROM AUTHOR]

Research has been conducted on the copper-zinc superoxide dismutase. The characterization of the truncated and full-length forms of the yeast copper chaperone for SOD has been carried out.

Force field analysis as a research tool is analyzed and discussed. Assessment in organizational change must consider three areas. The tool used must incorporate level analysis, diverse types of information from a plethora of variables and must account for dynamics of stability and change. A force field is constructed by choosing a change goal, actors of change, range of forces available and valuation of the forces according to their effectivity to change. The force must be potent and amenable to the actors.

The lack of correspondence between traditional economic development measures, such as GNP per capita, and human welfare measures, such as the PQLI, has been well documented in the literature. We devised and analyzed an economic development-welfare disparity measure, and found considerable geographic variability, with actual levels of human welfare much less than expected in many Middle Eastern and African countries, given the level of economic development. Exploratory correlation and regression analysis revealed that inequalities in the distribution of economic power and governmental expenditures contributed to the geographic variability. More importantly, each region improved its standing on the development-welfare disparity measure when relevant factors were controlled via multivariate regression. Key Words: economic development, human welfare, disparity measure, geographic variability.