JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. This content downloaded from 130.15.241.167 on Fri AbstractIn 1989, the IT function of the exploration and production division of British Petroleum Company set out to transform itself in response to a severe economic environment and poor internal perceptions of IT performance. This case study traces and analyzes 'Robert Zmud was the accepting senior editor for this paper. the changes made over six years. The authors derive a model of the transformed IT organization comprising seven components that they suggest can guide IT departments in general as they seek to reform themselves in the late 1990s.This model is seen to fit well with recent thinking on general management in that the seven components of change can be reclassified into the Bartlett and Ghoshal (1994) framework of purpose, process, and people. Some suggestions are made on how to apply the model in other organizations.

Extensive evidence favors the view that auxins cause at least their initial effect on cell elongation in shoot tissues by inducing the secretion of hydrogen ions from within the cells into the cell wall space outside them (4,15,20). Since in other systems proton export is known to result from activity of a membrane-bound ATPase (3, 9, 25, 28), it has been suggested that auxin probably activates an 10,21 were cut at the coleoptilar node and placed on ice. Both the coleoptiles and the primary leaves were used as starting material, since both contain the binding sites (24). Tissue was chopped and ground, as previously described (23), in one volume of homogenization buffer (50 mm Tris HCI, 1.0 mm disodium EDTA, 0.10 mM MgC62, 14 mM 2-mercaptoethanol, 0.25 M sucrose, (pH 8.0, normally saturated before use with PMSF3 to retard proteolytic degradation (8). After pressing the fluid through nylon cloth (2.7x 4 threads/mm), the filter cake was rehomogenized with 0.5 volume of buffer and the fluid was again pressed through the cloth. The filtrate was centrifuged at l0,OOOg (10 min) to remove debris and larger organelles. The supernatant fluid was then centrifuged at 145,000g (20 min) to pellet the microsomal fraction, which was washed with 10 mm sodium citrate-citric acid, 0.5 mm MgCl2, 0.25 M sucrose (pH 6.0) and repelleted at the same force. This pellet was finally homogenized in resuspension buffer (10 mm sodium citrate-citric acid, 5 iM MgCl2, 0.25 M sucrose (pH 5.5) (23) and then treated for 1 hr at 0 C with the indicated amount of Triton X-100. The sample was then recentrifuged at 145,000g (60 min) to pellet the unsolubilized material. The supernatant constituted the solubilized preparation used for auxinbinding and ATPase measurements.

Summary. Several unrelated compounds are known to selectively inhibit the development of the male gametophyte. When applied at suitable dosages to plants at the appropriate stages of anther development, these substances block the formation of fertile pollen. The affected stage of pollen development is characteristic of the specific chemical structure of the compound, ranging from effects on microspore meiosis to the formation of pollen defective in the ability to germinate or fertilize. The range of effects mediated by these substances, and by known male-sterile mutants, indicates that microspore development has several critical phases that are particularly sensitive to fatal inhibition. We propose that chemical inhibitors of pollen development deserve attention as tools for elucidating the regulation of pollen development.

An auxln-blndng protein can be soh_Ilize from microsoml anes of Zes mays using either Triton X-100 extraction of the mmbranes or buffer extraction of the acetone-precipitated membranes. This paper describes the properties of the biding protein so ld by thes two methods. The bndng is assayed by gel filtration chromatography in the presence of napbthalene 12-i4CIacetlc acid. Bing is rapid and reversible with an optium at pH 5. Both preparations show similar molecular weights by gel filtratio (80,000 daons) at pH 7.6 and 0