3-Dimensional architecture of the human multi-tRNA synthetase complex
NUCLEIC ACIDS RESEARCH
Authors: Khan, Krishnendu; Baleanu-Gogonea, Camelia; Willard, Belinda; Gogonea, Valentin; Fox, Paul L.
Abstract
In mammalian cells, eight cytoplasmic aminoacyltRNA synthetases (AARS), and three non-synthetase proteins, reside in a large multi-tRNA synthetase complex (MSC). AARSs have critical roles in interpretation of the genetic code during protein synthesis, and in non-canonical functions unrelated to translation. Nonetheless, the structure and function of the MSC remain unclear. Partial or complete crystal structures of all MSC constituents have been reported; however, the structure of the holo-MSC has not been resolved. We have taken advantage of cross-linking mass spectrometry (XL-MS) and molecular docking to interrogate the three-dimensional architecture of the MSC in human HEK293T cells. The XL-MS approach uniquely provides structural information on flexibly appended domains, characteristic of nearly all MSC constituents. Using the MS-cleavable cross-linker, disuccinimidyl sulfoxide, inter-protein cross-links spanning all MSC constituents were observed, including cross-links between eight protein pairs not previously known to interact. Intra-protein cross-links defined new structural relationships between domains in several constituents. Unexpectedly, an asymmetric AARS distribution was observed featuring a clustering of tRNA anti-codon binding domains on one MSC face. Possibly, the non-uniform localization improves efficiency of delivery of charged tRNA's to an interacting ribosome during translation. In summary, we show a highly compact, 3D structural model of the human holo-MSC.
Alignment of CanMEDS-Based Undergraduate and Postgraduate Pharmacy Curricula in The Netherlands
PHARMACY
Authors: Koster, Andries S.; Mantel-Teeuwisse, Aukje K.; Woerdenbag, Herman J.; Mulder, Wilhelmina M. C.; Wilffert, Bob; Schalekamp, Tom; Buurma, Henk; Wilting, Ingeborg; Westein, Marnix P. D.
Abstract
In this article the design of three master programs (MSc in Pharmacy) and two postgraduate specialization programs for community or hospital pharmacist is described. After a preceding BSc in Pharmacy, these programs cover the full pharmacy education capacity for pharmacists in primary and secondary health care in the Netherlands. All programs use the CanMEDS framework, adapted to pharmacy education and specialization, which facilitates the horizontal integration of pharmacists' professional development with other health care professions in the country. Moreover, it is illustrated that crossing the boundary from formal (university) education to experiential (workplace) education is eased by a gradual change in time spent in these two educational environments and by the use of comparable monitoring, feedback, and authentic assessment instruments. A reflection on the curricula, based on the principles of theIntegrative Pedagogy Modeland theSelf-determination Theory, suggests that the alignment of these educational programs facilitates the development of professional expertise and professional identity of Dutch pharmacists.