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Breeding of stress-tolerant plants is able to improve crop yield under stress conditions, whereas CRISPR/Cas9 genome editing has been shown to be an efficient way for molecular breeding to improve agronomic traits including stress tolerance in crops. However, genes can be targeted for genome editing to enhance crop abiotic stress tolerance remained largely unidentified. We have previously identified abscisic acid (ABA)-induced transcription repressors (AITRs) as a novel family of transcription factors that are involved in the regulation of ABA signaling, and we found that knockout of the entire family of AITR genes in Arabidopsis enhanced drought and salinity tolerance without fitness costs. Considering that AITRs are conserved in angiosperms, AITRs in crops may be targeted for genome editing to improve abiotic stress tolerance. We report here that mutation of GmAITR genes by CRISPR/Cas9 genome editing leads to enhanced salinity tolerance in soybean. By using quantitative RT-PCR analysis, we found that the expression levels of GmAITRs were increased in response to ABA and salt treatments. Transfection assays in soybean protoplasts show that GmAITRs are nucleus proteins, and have transcriptional repression activities. By using CRISPR/Cas9 to target the six GmAITRs simultaneously, we successfully generated Cas9-free gmaitr36 double and gmaitr23456 quintuple mutants. We found that ABA sensitivity in these mutants was increased. Consistent with this, ABA responses of some ABA signaling key regulator genes in the gmaitr mutants were altered. In both seed germination and seedling growth assays, the gmaitr mutants showed enhanced salt tolerance. Most importantly, enhanced salinity tolerance in the mutant plants was also observed in the field experiments. These results suggest that mutation of GmAITR genes by CRISPR/Cas9 is an efficient way to improve salinity tolerance in soybean.

Impairment of executive functions (EFs) was investigated in patients with cerebral hypoperfusion after cerebral angiostenosis/occlusion. Several EFs were measured in patients with cerebral angiostenosis/occlusion and healthy subjects. The vascular conditions, regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), mean transit time (MTT), time to peak (TTP), and delay time were assessed. The scores of the vascular stenosis/occlusion group were significantly lower than those of the control group. rCBV and rCBF were negatively correlated with the error response times in the Stroop test, and the persistent error responses in the Wisconsin Card Sorting Test (WCST) were positively correlated with the Montreal Cognitive Assessment (MoCA) scores. TTP was positively correlated with the reaction and error reaction times, and the persistent error response in WCST was negatively correlated with the times of sorting in WCST and MoCA scores. MTT was positively correlated with the persistent error response in WCST. In the Stroop test, delay time was positively correlated with response time, and negatively correlated with error response times, and the persistent error response in WCST and MoCA scores. Patients with cerebral hypoperfusion after cerebral angiostenosis/occlusion had executive dysfunctions in working memory, sustained attention, response inhibition, cognitive flexibility, thought organization, planning, and implementation. Moreover, their executive dysfunctions were related with the decline in rCBF and rCBV. The prolonged TTP, MTT, and delay time suggested a slow blood flow and the poor compensation of collateral circulation, resulting in impairment of the EFs.

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