53 research outputs found
A Method for the Rapid and Efficient Elution of Native Affinity-Purified Protein A Tagged Complexes
Nanoscale stiffness topography reveals structure and mechanics of the transport barrier in intact nuclear pore complexes
The nuclear pore complex (NPC) is the gate for transport between the cell nucleus and the cytoplasm. Small molecules cross the NPC by passive diffusion, but molecules larger than ∼5 nm must bind to nuclear transport receptors to overcome a selective barrier within the NPC1. Although the structure and shape of the cytoplasmic ring of the NPC are relatively well characterized2, 3, 4, 5, the selective barrier is situated deep within the central channel of the NPC and depends critically on unstructured nuclear pore proteins5, 6, and is therefore not well understood. Here, we show that stiffness topography7 with sharp atomic force microscopy tips can generate nanoscale cross-sections of the NPC. The cross-sections reveal two distinct structures, a cytoplasmic ring and a central plug structure, which are consistent with the three-dimensional NPC structure derived from electron microscopy2, 3, 4, 5. The central plug persists after reactivation of the transport cycle and resultant cargo release, indicating that the plug is an intrinsic part of the NPC barrier. Added nuclear transport receptors accumulate on the intact transport barrier and lead to a homogenization of the barrier stiffness. The observed nanomechanical properties in the NPC indicate the presence of a cohesive barrier to transport and are quantitatively consistent with the presence of a central condensate of nuclear pore proteins in the NPC channel
Working in a digital world: new leadership practices for the development of a digital library workforce
Complexity Theory for a New Managerial Paradigm: A Research Framework
In this work, we supply a theoretical framework of how organizations
can embed complexity management and sustainable development into their policies
and actions. The proposed framework may lead to a new management paradigm,
attempting to link the main concepts of complexity theory, change management,
knowledge management, sustainable development, and cybernetics. We highlight
how the processes of organizational change have occurred as a result of the move to
adapt to the changes in the various global and international business environments
and how this transformation has led to the shift toward the present innovation
economy. We also point how organizational change needs to deal with sustainability,
so that the change may be consistent with present needs, without compromising
the future
Management practices and performance of mergers and acquisitions in Pakistan: mediating role of psychological contract
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