Tank-binding kinase 1 (TBK1) is a Ser/Thr kinase that is involved in many intracellular processes, such as innate immunity, cell cycle, and apoptosis. TBK1 is also important for phosphorylating the autophagy adaptors that mediate the selective autophagic removal of damaged mitochondria. However, the mechanism by which PINK1-Parkin-mediated mitophagy activates TBK1 remains largely unknown. Here, we show that the autophagy adaptor optineurin (OPTN) provides a unique platform for TBK1 activation. Both the OPTN-ubiquitin and the OPTN-pre-autophagosomal structure (PAS) interaction axes facilitate assembly of the OPTN-TBK1 complex at a contact sites between damaged mitochondria and the autophagosome formation sites. At this assembly point, a positive feedback loop for TBK1 activation is initiated that accelerates hetero-autophosphorylation of the protein. Expression of monobodies engineered here to bind OPTN impaired OPTN accumulation at contact sites, as well as the subsequent activation of TBK1, thereby inhibiting mitochondrial degradation. Taken together, these data show that a positive and reciprocal relationship between OPTN and TBK1 initiates autophagosome biogenesis on damaged mitochondria.

To combat SARS-CoV-2 and any unknown emerging pathogens in the future, the development of a rapid and effective method to generate high-affinity antibodies or antibody-like proteins is of critical importance. We here report a high-speed in vitro selection of multiple high-affinity antibody-like proteins against various targets including the SARS-CoV-2 spike protein. The sequences of monobodies against the SARS-CoV-2 spike protein were successfully procured within only four days. Furthermore, the obtained monobody efficiently captured SARS-CoV-2 particles from the nasal swab samples of patients and exhibited a high neutralizing activity against SARS-CoV-2 infection (IC₅₀ = 0.5 nM). The high-speed in vitro selection of antibody-like proteins would be useful for the rapid development of a detection method and a neutralizing protein against a virus responsible for an ongoing, and possibly a future, pandemic.

Chronological life span is defined by how long a cell can survive in a non-dividing state. In yeast, it is measured by viability after entry into stationary phase. To date, some factors affecting chronological life span have been identified; however, the molecular details of how these factors regulate chronological life span have not yet been elucidated clearly. Because life span is a complicated phenomenon and is supposedly regulated by many factors, it is necessary to identify new factors affecting chronological life span to understand life span regulation. To this end, we have screened for long-lived mutants and identified Pma1, an essential P-type proton ATPase, as one of the determinants of chronological life span. We show that partial loss of Pma1 activity not only by mutations but also by treatment with the Pma1 inhibitory chemical vanadate resulted in the long-lived phenotype in Schizosaccharomyces pombe. These findings suggest a novel way to manipulate chronological life span by modulating Pma1 as a molecular target.

Chemical protein synthesis assisted by an organoruthenium catalyst streamlined the production of heterochromatin factors bearing various patterns of epigenetic modifications, and their biological significance was elucidated.

The influences of plasma parameters on the deposition of a-Si:H film and particle growth have been studied with silane discharge using amplitude-modulated RF methods. Plasma parameters have been measured with the Langmuir probe system and optical emission spectrometer. Behaviors and generation processes of particles have been observed by the laser scattering method. The deposited thin film has been characterized by various techniques such as Fourier-transform infrared (FT-IR) spectrometry, ESR and the constant photocurrent method (CPM). High deposition rate with low particle density as well as high film quality has been realized for a-Si:H film by amplitude-modulated RF methods.