Predictors of Postdeployment Functioning in Combat-Exposed U.S. Military Veterans.

Posttraumatic stress disorder (PTSD) and sequelae of mild traumatic brain injury (mTBI) are presumed to contribute to reintegration difficulties in combat-exposed veterans. Yet their relative impacts on postdeployment functioning are not well understood. The current study used structural equation modeling (SEM) to clarify the extent to which symptoms of internalizing disorders (e.g., depression, anxiety), mTBI symptoms, and cognitive performance are associated with functional impairment in 295 combat-exposed veterans. SEM results showed that internalizing symptoms most significantly predicted functional impairment (r = 0.72). Blast mTBI and cognitive performance were associated with internalizing (r = 0.24 and -0.25, respectively), but functional impairment was only modestly related to cognition (r = -0.17) and unrelated to mTBI. These results indicate that internalizing symptoms are the strongest predictor of functioning in trauma-exposed veterans, exceeding the effects of mTBI and cognitive performance. This evidence supports prioritizing interventions that target internalizing psychopathology to improve functioning in cases of co-occurring PTSD and mTBI.

Basic and acidic regions flanking the HMG-box domain of maize HMGB1 and HMGB5 modulate the stimulatory effect on the DNA binding of transcription factor Dof2.

The chromatin-associated high-mobility group (HMG) proteins of the plant HMGB family are characterized by a central HMG-box domain that is flanked by a basic N-terminal and an acidic C-terminal domain. By functional interaction with certain transcription factors, HMGB proteins contribute to transcriptional regulation. Previous work has shown that the maize HMGB5 protein is markedly more efficient than other HMGB proteins in stimulating the binding of transcription factor Dof2 to DNA target sites. Here we examine the structural requirements that determine the particular efficiency of HMGB5. The HMG-box domains of HMGB1 and HMGB5 (which mediate the interaction with Dof2) promoted Dof2-DNA binding to a similar extent, indicating that the terminal domains modulate the interaction with Dof2. Analysis of full-length, truncated, and chimeric HMGB1/5 proteins revealed that the acidic C-terminal domains positively influence the stimulation of Dof2-DNA binding, while the basic N-terminal domains have a rather negative effect. In particular, the C-terminal domain of HMGB5 has a striking positive effect and may account for the efficient stimulation mediated by full-length HMGB5. Interestingly, recombinant HMGB protein variants that have a relatively low affinity for linear DNA (such as proteins lacking the basic N-terminal domain) efficiently assist Dof2-DNA binding.