SnRK2.6 interacts with phytochrome B and plays a negative role in red light-induced stomatal opening.

Light is an important environmental factor for plant growth and development. Phytochrome B (phyB), a classical red/far-red light receptor, plays vital role in controlling plant photomorphogenesis and light-induced stomatal opening. Phytohormone abscisic acid (ABA) accumulates rapidly and triggers a series of physiological and molecular events during the responses to multiple abiotic stresses. Recent studies showed that phyB mutant synthesizes more ABA and exhibits improved tolerance to salt and cold stress, suggesting that a crosstalk exists between light and ABA signaling pathway. However, whether ABA signaling components mediate responses to light remains unclear. Here, we showed that SnRK2.6 (Sucrose Nonfermenting 1-Related Protein Kinase 2.6), a key regulator in ABA signaling, interacts with phyB and participates in light-induced stomatal opening. First, we checked the interaction between phyB and SnRK2s, and found that SnRK2.2/2.3/2.6 kinases physically interacted with phyB in yeast and in vitro. We also performed co-IP assay to support that SnRK2.6 interacts with phyB in plant. To investigate the role of SnRK2.6 in red light-induced stomatal opening, we obtained the snrk2.6 mutant and overexpression lines, and found that snrk2.6 mutant exhibited a significantly larger stomatal aperture under red light treatment, while the two independent overexpression lines showed significantly smaller stomatal aperture, indicative of a negative role for SnRK2.6 in red light-induced stomatal opening. The interaction of SnRK2.6 with red light receptor and the negative role of SnRK2.6 in red light-induced stomatal opening provide new evidence for the crosstalk between ABA and red light in guard cell signaling.

[Assessment of cognitive function, emotions and activities of daily living in patients with multiple system atrophy].

OBJECTIVE: To explore the cognitive function, emotional status and activities of daily living in patients with multiple system atrophy (MSA). METHODS: Thirty-two MSA patients and 38 healthy controls from October 2009 to November 2012 were recruited from our hospital. Their cognitive function, emotional status and activities of daily living were assessed. Cognitive function was assessed by Montreal cognitive assessment (MoCA) and mini-mental state examination (MMSE); emotional status by self-rating depression scale (SDS) and self-rating anxiety scale (SAS); daily living and activities by activities of daily living scale (ADL). Data analysis was performed with SPSS 19.0. And the results were presented as the mean ± standard deviation. Comparison of means was performed with independent sample t test. And Pearson's correlation test was used for correlation analysis. A P-value <0.05 was considered significant. RESULTS: Mild or moderate cognitive impairment was documented in 71.9% of MSA patients. The scores of MoCA and MMSE in the MSA group were significantly lower than those in the control group. And the scores of ADL, SDS and SAS in the MSA group were significantly higher than those in the control group (P < 0.05). MoCA subitems such as space/executive function, attention, abstraction, language and delayed memory of the MSA group were significantly lower than those of the control group (P < 0.05). A negative correlation existed between the scores of MoCA and MMSE with disease duration (P < 0.01). There was a positive correlation between the scores of SDS and SAS with ADL and disease duration (P < 0.05). And the relationship was significant between the scores of SDS and SAS (P < 0.01). A positive correlation existed between scores of ADL with disease duration (P < 0.05). CONCLUSION: MSA patients have certain degrees of cognitive impairment, emotion disorders and impaired ADL. Cognitive impairment in MSA patients may be more common than previously. Furthermore, the clinical features of cognitive impairment in these patients may have some clinical values for references.

[Comparative study on diagnostic significance of urethral sphincter versus external anal sphincter electromyography in patients with multiple system atrophy].

OBJECTIVE: To evaluate the diagnostic value of external anal sphincter electromyography (EAS-EMG) versus urethral sphincter electromyography (US-EMG) in patients with multiple system atrophy (MSA). METHODS: A total of 27 MSA patients were examined with EAS and US-EMG as treatment group while 28 non-MSA subjects as control group. Spontaneous activities during relaxation, mean duration & amplitude of motor unit potential (MUP), percentage of polyphasic and variations during strong contraction were recorded and analyzed statistically. RESULTS: There was significant difference in light contraction between MSA and non-MSA cases on both EAS-EMG and US-EMG (EAS-EMG, P < 0.001; US-EMG, P = 0.002) . Meanwhile, strong contraction and percentage of polyphasic showed significant differences between MSA and non-MSA cases on EAS-EMG only (strong contraction, P = 0.016; percentage of polyphasic, P = 0.004) . EAS-EMG showed more significant changes in neurogenic injury than US-EMG. CONCLUSIONS: US-EMG and EAS-EMG are valuable for the diagnosis of MSA. The differences of multiple parameters of EAS-EMG were more significant than those of US-EMG for MSA cases. US-EMG may serve as a supplement of EAS-EMG in case of restriction.