Protein Dynamics in Complex DNA Lesions

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The protective activity of 2 normal immunoglobulin preparations for intravenous administration in experimental Pseudomonas aeruginosa infection

The antibody levels in 18 batches of the preparations of human immunoglobulin, Immunovenin and Immunovenin-Intact, for intravenous injection were determined in the enzyme immunoassay with the use of the mixture of P. aeruginosa lipopolysaccharide antigens of seven immunotypes. The average antibody titers in these preparations were identical. The preparations were found to have protective action against P. aeruginosa experimental infection in mice.     

Behavior of dominant and non dominant arms during ballistic protractive target-directed movements

The purpose of this study is to investigate the asymmetry of dominant and non-dominant arms regarding reaction time (RT), velocity, force and power generated during ballistic target-directed movements. Fifty six, right-handed young males performed protractile movements with both arms separately by pushing a joystick towards a target-line as quickly and as accurately as possible. Participants performed 21 repetitions with each hand. The temporal, spatial, kinetic and kinematic parameters were computed. All movements were grouped regarding their accuracy (when joystick fell short, stopped precisely or overreached the target). Each group of movements was analyzed separately and the data obtained was compared across groups. The results showed that although the left arm was less accurate than the right one, it reached the target significantly faster, developing greater average force and power. The forces of acceleration and deceleration of the left arm were greater too. We did not observe a significant lateral difference in RT in situations when the arm fell short of the target, or stopped precisely on the target. It was only when the target was overreached that the left arm displayed a significantly greater RT than the right one. We explain the results from the asymmetry of motor behavior in favor of the influence of both hemispheres in this process.     

Common formin-regulating sequences in Smy1 and Bud14 are required for the control of actin cable assembly in vivo

Formins comprise a large family of proteins with diverse roles in remodeling the actin cytoskeleton. However, the spatiotemporal mechanisms used by cells to control formin activities are only beginning to be understood. Here we dissected Smy1, which has dual roles in regulating formins and myosin. Using mutagenesis, we identified specific sequences in Smy1 critical for its in vitro inhibitory effects on the FH2 domain of the formin Bnr1. By integrating smy1 alleles targeting those sequences, we genetically uncoupled Smy1’s functions in regulating formins and myosin. Quantitative imaging analysis further demonstrated that the ability of Smy1 to directly control Bnr1 activity is crucial in vivo for proper actin cable length, shape, and velocity and, in turn, efficient secretory vesicle transport. A Smy1-like sequence motif was also identified in a different Bnr1 regulator, Bud14, and found to be essential for Bud14 functions in regulating actin cable architecture and function in vivo. Together these observations reveal unanticipated mechanistic ties between two distinct formin regulators. Further, they emphasize the importance of tightly controlling formin activities in vivo to generate specialized geometries and dynamics of actin structures tailored to their physiological roles.