Examination of respiratory syncytial virus fusion protein proteolytic processing and roles of the P27 domain.

The respiratory syncytial virus (RSV) fusion protein (F) facilitates virus-cell membrane fusion, which is critical for viral entry, and cell-cell fusion. In contrast to many type I fusion proteins, RSV F must be proteolytically cleaved at two distinct sites to be fusogenic. Cleavage at both sites results in the release of a 27 amino-acid fragment, termed Pep27.

Paramyxoviruses: Pathogenesis, Vaccines, Antivirals, and Prototypes for Pandemic Preparedness.

The Paramyxoviridae family includes established human pathogens such as measles virus, mumps virus, and the human parainfluenza viruses; highly lethal zoonotic pathogens such as Nipah virus; and a number of recently identified agents, such as Sosuga virus, which remain poorly understood. The high human-to-human transmission rate of paramyxoviruses such as measles virus, high case fatality rate associated with other family members such as Nipah virus, and the existence of poorly characterized zoonotic pathogens raise concern that known and unknown paramyxoviruses have significant pandemic potential. In this review, the general life cycle, taxonomic relationships, and viral pathogenesis are described for paramyxoviruses that cause both systemic and respiratory system-restricted infections.

Imaging analysis reveals budding of filamentous human metapneumovirus virions and direct transfer of inclusion bodies through intercellular extensions.

Human metapneumovirus is an important respiratory pathogen that causes significant morbidity and mortality, particularly in the very young, the elderly, and the immunosuppressed. However, the molecular details of how this virus spreads to new target cells are unclear. This work provides important new information on the formation of filamentous structures that are consistent with virus particles and adds critical new insight into the structure of extensions between cells that form during infection.

The RSV F p27 peptide: current knowledge, important questions.

Respiratory syncytial virus (RSV) remains a leading cause of hospitalizations and death for young children and adults over 65. The worldwide impact of RSV has prioritized the search for an RSV vaccine, with most targeting the critical fusion (F) protein. However, questions remain about the mechanism of RSV entry and RSV F triggering and fusion promotion.

Specific Residues in the C-Terminal Domain of the Human Metapneumovirus Phosphoprotein Are Indispensable for Formation of Viral Replication Centers and Regulation of the Function of the Viral Polymerase Complex.

Human metapneumovirus (HMPV) is a negative-strand RNA virus that frequently causes respiratory tract infections in infants, the elderly, and the immunocompromised. A hallmark of HMPV infection is the formation of membraneless, liquid-like replication and transcription centers in the cytosol termed inclusion bodies (IBs). The HMPV phosphoprotein (P) and nucleoprotein (N) are the minimal viral proteins necessary to form IB-like structures, and both proteins are required for the viral polymerase to synthesize RNA during infection.