SiaA/D interconnects c-di-GMP and RsmA signaling to coordinate cellular aggregation of Pseudomonas aeruginosa in response to environmental conditions

© 2016 Colley, Dederer, Carnell, Kjelleberg, Rice and Klebensberger. Pseudomonas aeruginosa has emerged as an important opportunistic human pathogen that is often highly resistant to eradication strategies, mediated in part by the formation of multicellular aggregates. Cellular aggregates may occur attached to a surface (biofilm), at the air-liquid interface (pellicle), or as suspended aggregates. Compared to surface attached communities, knowledge about the regulatory processes involved in the formation of suspended cell aggregates is still limited. We have recently described the SiaA/D signal transduction module that regulates macroscopic cell aggregation during growth with, or in the presence of the surfactant SDS. Targets for SiaA/D mediated regulation include the Psl polysaccharide, the CdrAB two-partner secretion system and the CupA fimbriae. While the global regulators c-di-GMP and RsmA are known to inversely coordinate cell aggregation and regulate the expression of several adhesins, their potential impact on the expression of the cupA operon remains unknown. Here, we investigated the function of SiaA (a putative ser/thr phosphatase) and SiaD (a di-guanylate cyclase) in cupA1 expression using transcriptional reporter fusions and qRT-PCR. These studies revealed a novel interaction between the RsmA posttranscriptional regulatory system and SiaA/D mediated macroscopic aggregation. The RsmA/rsmY/Z system was found to affect macroscopic aggregate formation in the presence of surfactant by impacting the stability of the cupA1 mRNA transcript and we reveal that RsmA directly binds to the cupA1 leader sequence in vitro. We further identified that transcription of the RsmA antagonist rsmZ is controlled in a SiaA/D dependent manner during growth with SDS. Finally, we found that the siaD transcript is also under regulatory control of RsmA and that overproduction of RsmA or the deletion of siaD results in decreased cellular cyclic di-guanosine monophosphate (c-di-GMP) levels quantified by a transcriptional reporter, demonstrating that SiaA/D connects c-di-GMP and RsmA/rsmY/Z signaling to reciprocally regulate cell aggregation in response to environmental conditions

Mechanism of human PINK1 activation at the TOM complex in a reconstituted system

Loss-of-function mutations in PTEN-induced kinase 1 (PINK1) are a frequent cause of early-onset Parkinson’s disease (PD). Stabilization of PINK1 at the translocase of outer membrane (TOM) complex of damaged mitochondria is critical for its activation. The mechanism of how PINK1 is activated in the TOM complex is unclear. Here, we report that co-expression of human PINK1 and all seven TOM subunits in Saccharomyces cerevisiae is sufficient for PINK1 activation. We use this reconstitution system to systematically assess the role of each TOM subunit toward PINK1 activation. We unambiguously demonstrate that the TOM20 and TOM70 receptor subunits are required for optimal PINK1 activation and map their sites of interaction with PINK1 using AlphaFold structural modeling and mutagenesis. We also demonstrate an essential role of the pore-containing subunit TOM40 and its structurally associated subunits TOM7 and TOM22 for PINK1 activation. These findings will aid in the development of small-molecule activators of PINK1 as a therapeutic strategy for PD

The impact of in-service professional development on the quality of teacher-child interactions in early education and care: A meta-analysis

High-quality interactions between young children and teachers in early childhood education and care (ECEC) are the cornerstone of educational quality. International findings suggest that the quality of interactions that support emotions and classroom organization is at a medium to high level, but the quality of instructional support is at a lower level. Within the “Teaching Through Interactions” framework developed by Hamre and colleagues (2013), several efforts were made to evaluate and improve key teacher-child interactions through in-service training. Our review includes experimental studies that evaluate professional development using the Classroom Assessment Scoring System measures. The systematic literature search and coding of studies was carried out by two independent reviewers. Our review includes 15 recent studies with 18 treatments. The meta-analysis (random effect model) showed an overall statistically significant professional development effect of g = 0.39 (SE = .08), i.e. close to a medium-size effect. In addition, effect sizes were almost equal for interactions related to emotional support, classroom organization, and instructional support (g= 0.35, 0.30, and 0.43, respectively). The quality of experimental studies and professional development was at a high level (e.g., individual component, feedback, or modeling) and experimental findings were generally positive. Our meta-analysis indicates that high-quality in-service programs have the strength to improve teacher-child interactions and pedagogical quality across all three domains

Über die Inhaltsstoffe des grünen Knollenblätterpilzes, LIX. Die Raumstruktur der Phallotoxine

Die Thioetherbrücke [CH2 ‐ S ‐ C(α‐indol)] in den Phallotoxinen ist ein inhärent dissymmetrischer Chromophor, der die positiven Cottoneffekte um 290 nm im CD‐Spektrum verursacht. Bei einer früheren Strukturanalyse durch 1H‐NMR konnte die M‐ oder P‐Helizität dieses Strukturelements nicht eindeutig bestimmt werden. Das einfacher gebaute cyclische Thioethertripeptid 2‐Mercapto‐L‐tryptophylglycylcystein‐cyclosulfid (1 → 3) (2a) weist im CD‐Spektrum um 290 nm zu denen der Phallotoxine genau spiegelbildliche negative Cottoneffekte (Abb. 1) auf. Die Strukturanalyse von 2a durch 1H‐NMR (360 MHz) führte zu einem Strukturvorschlag mit M‐Helizität. Das N‐p‐Brombenzolsulfonylderivat 2c mit analogem CD‐Spektrum bildete mit Aceton Kristalle, die zur Röntgenstrukturanalyse geeignet waren. Die dadurch erhaltene Raumformel zeigt für das fragliche Strukturelement negative M‐Helizität. Demnach enthalten die Phallotoxine den spiegelbildlich analogen Chromophor mit positiver P‐Helizität. Die Einführung eines weiteren chiralen Zentrums in den Peptidring (2b: L‐Alanin statt Glycin in 2a) hat auf die Gestalt des CD‐Spektrums keinen Einfluß

Replacement of ovocytes in the ovary of normal and hormone-injected young rats

No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49743/1/1090790112_ftp.pd