The Future of the Clean Development Mechanism. Note on the report “A Call to Action” of the High-Level Panel on CDM Policy Dialogue. CEPS Special Report No. 71, 20 November 2012

The clean development mechanism (CDM) has been through a long and complex growing process since it was approved as part of the Kyoto Protocol. It was designed within the framework of the UNFCCC and the Kyoto Protocol, and reflected the political and economic realities of that time. To ensure its continued effectiveness in contributing to future global climate action and to reflect on how best to position the CDM to respond to future challenges, a high-level panel (HLP) was formed at the Durban climate change conference in 2011. Following extensive consultations, the panel published its report in September 2012. Through this Special Report, the CEPS Carbon Market Forum offers its reflections on findings and recommendations of the HLP, as well as, by extension, its own views on the future of the CDM. In the context of the latter, it explores the following questions: Is there a need for an instrument such as the CDM in the future? What ‘demand’ can it fill? In the roles identified under the first question, what can be done to adapt it and also continue to increase its efficacy?

Ribonucleocapsid formation of severe acute respiratory syndrome coronavirus through molecular action of the N-terminal domain of N protein

Conserved among all coronaviruses are four structural proteins: the matrix (M), small envelope (E), and spike (S) proteins that are embedded in the viral membrane and the nucleocapsid phosphoprotein (N), which exists in a ribonucleoprotein complex in the lumen. The N-terminal domain of coronaviral N proteins (N-NTD) provides a scaffold for RNA binding, while the C-terminal domain (N-CTD) mainly acts as oligomerization modules during assembly. The C terminus of the N protein anchors it to the viral membrane by associating with M protein. We characterized the structures of N-NTD from severe acute respiratory syndrome coronavirus (SARS-CoV) in two crystal forms, at 1.17 A (monoclinic) and at 1.85 A (cubic), respectively, resolved by molecular replacement using the homologous avian infectious bronchitis virus (IBV) structure. Flexible loops in the solution structure of SARS-CoV N-NTD are now shown to be well ordered around the beta-sheet core. The functionally important positively charged beta-hairpin protrudes out of the core, is oriented similarly to that in the IBV N-NTD, and is involved in crystal packing in the monoclinic form. In the cubic form, the monomers form trimeric units that stack in a helical array. Comparison of crystal packing of SARS-CoV and IBV N-NTDs suggests a common mode of RNA recognition, but they probably associate differently in vivo during the formation of the ribonucleoprotein complex. Electrostatic potential distribution on the surface of homology models of related coronaviral N-NTDs suggests that they use different modes of both RNA recognition and oligomeric assembly, perhaps explaining why their nucleocapsids have different morphologies.