Drought causes crop losses worldwide, and its impact is expected to increase as the world warms. This has motivated the development of small-molecule tools for mitigating the effects of drought on agriculture. We show here that current leads are limited by poor bioactivity in wheat, a widely grown staple crop, and in tomato. To address this limitation, we combined virtual screening, x-ray crystallography, and structure-guided design to develop opabactin (OP), an abscisic acid (ABA) mimic with up to an approximately sevenfold increase in receptor affinity relative to ABA and up to 10-fold greater activity in vivo. Studies in Arabidopsis thaliana reveal a role of the type III receptor PYRABACTIN RESISTANCE-LIKE 2 for the antitranspirant efficacy of OP. Thus, virtual screening and structure-guided optimization yielded newly discovered agonists for manipulating crop abiotic stress tolerance and water use.

Fragile X syndrome (FXS) is a leading genetic cause of autism with symptoms that include sensory processing deficits. In both humans with FXS and a mouse model [Fmr1 knockout (KO) mouse], electroencephalographic (EEG) recordings show enhanced resting state gamma power and reduced sound-evoked gamma synchrony. We previously showed that elevated levels of matrix metalloproteinase-9 (MMP-9) may contribute to these phenotypes by affecting perineuronal nets (PNNs) around parvalbumin (PV) interneurons in the auditory cortex of Fmr1 KO mice. However, how different cell types within local cortical circuits contribute to these deficits is not known. Here, we examined whether Fmr1 deletion in forebrain excitatory neurons affects neural oscillations, MMP-9 activity, and PV/PNN expression in the auditory cortex. We found that cortical MMP-9 gelatinase activity, mTOR/Akt phosphorylation, and resting EEG gamma power were enhanced in CreNex1/Fmr1Flox/y conditional KO (cKO) mice, whereas the density of PV/PNN cells was reduced. The CreNex1/Fmr1Flox/y cKO mice also show increased locomotor activity, but not the anxiety-like behaviors. These results indicate that fragile X mental retardation protein changes in excitatory neurons in the cortex are sufficient to elicit cellular, electrophysiological, and behavioral phenotypes in Fmr1 KO mice. More broadly, these results indicate that local cortical circuit abnormalities contribute to sensory processing deficits in autism spectrum disorders.

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Introduction: Neuropsychiatric symptoms occur in 30% to 40% of patients living with systemic lupus erythematosus (SLE). Brain imaging may play a pivotal role in determining the etiology as it did for the case presented here. Methods: A new case of central nervous system (CNS) SLE is presented along with an analysis of 33 comparable cases from the scientific literature. Results: A 70-year-old female with subacute cutaneous lupus presented to a university-based geropsychiatry program after 1 year of benign visual hallucinations and several months of shuffling gait, recurrent falls, and forgetfulness. These symptoms were highly suggestive of Lewy body dementia; however, the patient’s history of basal ganglia infarct, cognitive testing demonstrating inattention and executive dysfunction, and follow-up brain imaging, which did not reveal acute findings, aligned with cerebral pathology previously attributed to vasculitis and supported the diagnosis of subcortical dementia due to SLE-CNS vasculitis. Oral prednisone 20 mg daily resolved her symptoms. Over the next 19 months, her prednisone was tapered completely and her symptoms did not return. A systematic literature search identified 33 comparable cases. Conclusion: An analysis of previously published cases suggests that extending the duration of the prednisone taper beyond 1 year may decrease the risk of later occurring neuropsychiatric symptoms in this patient population.