Advances on the structure of the R2TP/Prefoldin-like complex

Cellular stability, assembly and activation of a growing list of macromolecular complexes require the action of HSP90 working in concert with the R2TP/Prefoldin-like (R2TP/PFDL) co-chaperone. RNA polymerase II, snoRNPs and complexes of PI3-kinase-like kinases, a family that includes the ATM, ATR, DNA-PKcs, TRAPP, SMG1 and mTOR proteins, are among the clients of the HSP90-R2TP system. Evidence links the R2TP/PFDL pathway with cancer, most likely because of the essential role in pathways commonly deregulated in cancer. R2TP forms the core of the co-cochaperone and orchestrates the recruitment of HSP90 and clients, whereas prefoldin and additional prefoldin-like proteins, including URI, associate with R2TP, but their function is still unclear. The mechanism by which R2TP/PFLD facilitates assembly and activation of such a variety of macromolecular complexes is poorly understood. Recent efforts in the structural characterization of R2TP have started to provide some mechanistic insights. We summarize recent structural findings, particularly how cryo-electron microscopy (cryo-EM) is contributing to our understanding of the architecture of the R2TP core complex. Structural differences discovered between yeast and human R2TP reveal unanticipated complexities of the metazoan R2TP complex, and opens new and interesting questions about how R2TP/PFLD works

The impact of perceived discrimination on depressive symptoms and the role of differentiated social support among immigrant populations in South Korea

Abstract Background Previous studies demonstrated a positive association between perceived discrimination and mental health problems among immigrants in countries that traditionally host immigrants. Recent trends in international migration show that there has been a significant increase in immigrant populations in East Asian countries. These newer host countries have different social contexts from traditional ones, yet mental health among these immigrants and its relationship to discrimination are under-researched. Thus, this study aimed to examine the association between perceived discrimination and depressive symptoms among immigrants in one of the newer host countries, South Korea. Moreover, we investigated if differentiated social support (ethnic, host or other support) serves as a moderator of discrimination for depressive symptoms. Methods This study used survey data from the 2012 Korean Social Survey on Foreign Residents (N = 1068), restricted to adults 20 years or older. Multiple linear regression models were conducted to estimate the association between perceived discrimination, social support, and depressive symptoms among immigrants in South Korea. Results Perceived discrimination showed a strong positive association with depressive symptoms among immigrants, and ethnic and host support was directly positively associated with depressive symptoms. Furthermore, ethnic support moderated the effects of perceived discrimination on depressive symptoms. Conclusion Community-level interventions providing immigrants opportunities to increase social networking members from the same country as well as the native-born in a host country may be helpful resources for improving mental health among immigrants in South Korea. Also, raising awareness of racial discrimination among members in South Korea would be crucial