Protein complexes are under evolutionary selection to assemble via ordered pathways

Is the order in which proteins assemble into complexes important for biological function? Here, we seek to address this by searching for evidence of evolutionary selection for ordered protein complex assembly. First, we experimentally characterize the assembly pathways of several heteromeric complexes and show that they can be simply predicted from their three-dimensional structures. Then, by mapping gene fusion events identified from fully sequenced genomes onto protein complex assembly pathways, we demonstrate evolutionary selection for conservation of assembly order. Furthermore, using structural and high-throughput interaction data, we show that fusion tends to optimize assembly by simplifying protein complex topologies. Finally, we observe protein structural constraints on the gene order of fusion that impact the potential for fusion to affect assembly. Together, these results reveal the intimate relationships among protein assembly, quaternary structure, and evolution and demonstrate on a genome-wide scale the biological importance of ordered assembly pathways

Identificando a branquidade inominada: corpo, raça e nação nas representações sobre Gisele Bündchen na mídia transnacional Identifying the un-named whiteness: race, body, and nation in representations of Gisele Bündchen in the transnational media

Este artigo examina as configurações discursivas que associam o corpo da top model Gisele Bündchen ao corpo da nação brasileira, e analisa as formas como essas configurações definem o que significa ser brasileira/o de acordo com os discursos presentes nas mídias brasileira e transnacional. Para tanto, utilizo imagens de Gisele a fim de interrogar as formações raciais em um e outro contexto, e de examinar como tais formações têm se reconfigurado a partir das recentes mudanças demográficas e políticas nos contextos brasileiro e estadunidense. Alinho-me, nesse sentido, aos estudos sobre relações raciais, adotando aqui a perspectiva desenvolvida pelos estudos críticos sobre branquidade.<br>This article examines the discursive configurations that associate the body of top model Gisele Bündchen to the body of the Brazilian nation, and analyses the ways through which these configurations define what means to be Brazilian according to discourses that circulate in Brazilian and transnational media. In order to do that, I use images of Gisele to interrogate the racial formations in the two contexts and to examine how theses formations are being reconfigured due to recent changes in the demographic and political contexts in Brazil and in the United States. Following the studies of racial relations in the two countries, I adopt a framework developed by the studies that focus on the construction of whiteness