Coordination of actin plus-end dynamics by IQGAP1, formin, and capping protein.

Cell processes require precise regulation of actin polymerization that is mediated by plus-end regulatory proteins. Detailed mechanisms that explain plus-end dynamics involve regulators with opposing roles, including factors that enhance assembly, e.g., the formin mDia1, and others that stop growth (capping protein, CP). We explore IQGAP1's roles in regulating actin filament plus-ends and the consequences of perturbing its activity in cells. We confirm that IQGAP1 pauses elongation and interacts with plus ends through two residues (C756 and C781). We directly visualize the dynamic interplay between IQGAP1 and mDia1, revealing that IQGAP1 displaces the formin to influence actin assembly. Using four-color TIRF, we show that IQGAP1's displacement activity extends to formin-CP "decision complexes," promoting end-binding protein turnover at plus-ends. Loss of IQGAP1 or its plus-end activities disrupts morphology and migration, emphasizing its essential role. These results reveal a new role for IQGAP1 in promoting protein turnover on filament ends and provide new insights into how plus-end actin assembly is regulated in cells.

Coordination of actin plus-end dynamics by IQGAP1, formin, and capping protein.

Cell processes require precise regulation of actin polymerization that is mediated by plus-end regulatory proteins. Detailed mechanisms that explain plus-end dynamics involve regulators with opposing roles, including factors that enhance assembly, e.g., the formin mDia1, and others that stop growth (Capping Protein, CPz). We explore IQGAP1's roles regulating actin filament plus-ends and the consequences of perturbing its activity in cells. We confirm that IQGAP1 pauses elongation and interacts with plus ends through two residues (C756 and C781). We directly visualize the dynamic interplay between IQGAP1 and mDia1, revealing that IQGAP1 displaces the formin to influence actin assembly. Using four-color TIRF we show that IQGAP1's displacement activity extends to formin-CPz 'decision complexes', promoting end-binding protein turnover at plus-ends. Loss of IQGAP1 or its plus-end activities disrupts morphology and migration, emphasizing its essential role. These results reveal a new role for IQGAP1 in promoting protein turnover on filament ends and provide new insights into how plus-end actin assembly is regulated in cells.

Asynchronous assessment with the PCL-5: Practice considerations and recommendations.

The posttraumatic stress disorder (PTSD) Checklist for the Diagnostic and Statistical Manual of Mental Disorders-5 (PCL-5; Weathers et al., 2013) is a well-validated self-report instrument intended to assess provisional diagnostic status and symptom severity of PTSD. With the recent release of the Department of Veterans Affairs measurement-based care initiative, the PCL-5 is now required to be used by VA-based PTSD Specialty Clinics to track and monitor patient progress in treatment. With the rise of telehealth modalities in response to the COVID pandemic, clinicians have turned to remote, asynchronous assessment (i.e., assessments completed without the provider present through remote platforms) as a means to provide best care to virtual patients and reduce time burden on providers. We review the psychometric properties of the PCL-5 along with relevant criticisms of the measure to provide recommendations for its optimal use through remote, asynchronous means. We also explore considerations for using remote, asynchronous assessment to assist with measurement-based care more broadly. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

An ecological approach to understanding the impact of sexual violence: a systematic meta-review.

Aim: A systematic meta-review was conducted to examine (1) the broad range of negative and positive individual and interpersonal changes following adult sexual violence, as well as (2) the risk/protective factors at multiple levels of the social ecology (e.g., individual, assault, and micro/meso/exo/macro/chronosystem factors)-influencing the impact of sexual violence. Methods: Searches of Web of Science, Pubmed, and ProQuest resulted in inclusion of 46 systematic reviews or meta-analyses. Review findings were extracted for summary and a deductive thematic analysis was conducted. Results: Experiencing sexual violence is associated with many negative individual and sexual difficulties as well as revictimization risk. Only a limited number of reviews reported on interpersonal and positive changes. Factors at multiple levels of the social ecology play a role in the intensity of these changes. Reviews including macrolevel factors were non-existent, however. Conclusion: Reviews on sexual violence are fragmented in nature. Although the use of an ecological approach is often lacking, adopting such a perspective in research is necessary for a fuller understanding of the multiple influences on survivor outcomes. Future research should evaluate the occurrence of social and positive changes following sexual violence, as well as the role of macrolevel factors in influencing post-assault outcomes.

Received support in the aftermath of Hurricane Florence: reciprocal relations among perceived support, community solidarity, and PTSD.

Background and Objectives: The social support deterioration model (SSDM) posits that individuals who do not receive adequate support following a disaster are vulnerable to losses in community solidarity and perceived support, as well as the development of persistent distress. However, limited longitudinal research has evaluated the relations among support and these outcomes among disaster-affected individuals. Design: The current study utilized random intercept cross-lagged panel modeling (RI-CLPM) to examine reciprocal relations among received support, community solidarity, perceived support, and posttraumatic stress disorder (PTSD) symptoms among rural Hurricane Florence survivors (n = 261) assessed 5-8 months post-hurricane (T1), and then at two more timepoints at three-month intervals (T2 and T3). Results: Results of the RI-CLPM supported that lower received support at T2 was associated with decreases in community solidarity at T3, and higher perceived support at T1 was associated with increases in received support at T2. In supplemental analyses, higher received support at T2 was associated with lower PTSD symptoms at T3. Conclusions: Consistent with the SSDM, individuals who receive less support post-disaster are vulnerable to losses in community solidarity and potentially persistent PTSD symptoms. Conversely, those with stronger support networks may be better able to access needed support in the longer-term.