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Plant roots are sustained through meristem activity at the root tip. Two transcriptional pathways, one mediated by PLETHORAs (PLTs) and the other by SHORTROOT and SCARECROW, play major roles in root meristem development. The role of PLTs during root meristem development requires a concentration gradient, which is not only contributed by posttranslational regulation such as growth dilution and intercellular movement but also likely by a largely unknown fine-tuned transcriptional regulatory mechanism. We report here that Arabidopsis (Arabidopsis thaliana) JANUS positively regulates PLT1 expression in the root meristem by recruiting RNA polymerase II (Pol II) to PLT1 and by interacting with PLT1. JANUS-dependent recruitment of Pol II is inhibited through the competitive binding of JANUS by GRF-INTERACTING FACTOR1 (GIF1)/ANGUSTIFOLIA3, a transcriptional cofactor that negatively regulates PLT1 expression. Finally, GIF1 and JANUS, the antagonistic regulators of PLT1, both depend on Arabidopsis IMPORTIN β4 for their nuclear accumulation. The combination of an importin and its two antagonistic cargos in PLT1 transcription may have logistic benefits in fine-tuning the transcription of PLT1 in root meristem.

Summary Embryonic pattern formation relies on positional coordination of cell division and specification. Early axis formation during Arabidopsis embryogenesis requires WUSCHEL RELATED HOMEOBOX (WOX)-mediated transcription activation and PIN-FORMED7 (PIN7)-mediated auxin asymmetry. How these events are regulated is obscure. We report that Arabidopsis JANUS, a putative subunit of spliceosome, is essential for embryonic pattern formation. Significantly reduced transcription but not mRNA processing of WOX2 and PIN7 in janus suggested its role in transcriptional regulation. JANUS interacts with RNA polymerase II (Pol II) through a region outside of its spliceosome-association domain. We further show that Pol II mediates the transcription of WOX2 and PIN7 in a JANUS-dependent way and is essential for embryonic pattern formation. These findings reveal that JANUS recruits Pol II for the activation of two parallel pathways to ensure proper pattern formation during embryogenesis., Graphical Abstract, Highlights • Arabidopsis JANUS, a putative spliceosome subunit, is essential for embryogenesis • JANUS mediates the transcription but not RNA processing of WOX2 and PIN7 • JANUS interacts with RNA polymerase II whose mutations caused embryo lethality • Pol II mediates the transcription of WOX2 and PIN7 in a JANUS-dependent manner, Biological Sciences; Molecular Biology; Plant Biology; Plant Development

Plant roots are sustained through meristem activity at the root tip. Two transcriptional pathways, one mediated by PLETHORAs (PLTs) and the other by SHORTROOT and SCARECROW, play major roles in root meristem development. The role of PLTs during root meristem development requires a concentration gradient, which is not only contributed by posttranslational regulation such as growth dilution and intercellular movement but also likely by a largely unknown fine-tuned transcriptional regulatory mechanism. We report here that Arabidopsis (Arabidopsis thaliana) JANUS positively regulates PLT1 expression in the root meristem by recruiting RNA polymerase II (Pol II) to PLT1 and by interacting with PLT1. JANUS-dependent recruitment of Pol II is inhibited through the competitive binding of JANUS by GRF-INTERACTING FACTOR1 (GIF1)/ANGUSTIFOLIA3, a transcriptional cofactor that negatively regulates PLT1 expression. Finally, GIF1 and JANUS, the antagonistic regulators of PLT1, both depend on Arabidopsis IMPORTIN β4 for their nuclear accumulation. The combination of an importin and its two antagonistic cargos in PLT1 transcription may have logistic benefits in fine-tuning the transcription of PLT1 in root meristem.

There is growing concern in West Africa about the spread of the Ebola hemorrhagic fever virus. With the increasing global public health risk, a coordinated international response is necessary. The Chinese government is prepared to work in collaboration with West African countries to assist in the containment and control of the epidemic through the contribution of medical expertise and mobile laboratory testing teams. Nationally, China is implementing prevention programs in major cities and provinces, the distribution of Ebola test kits, and the deployment of a new national Ebola research laboratory. (Disaster Med Public Health Preparedness. 2015;0:1-2)

To explore the mental health status of residents scattered living in Anxian after Wenchuan earthquake so as to provide scientific basis for further mental health intervention.A face to face interview was conducted among the scattered residents with designed questionnaire, which had three parts of the physical and emotional reaction, the relax methods and the social care and supports expected. Two-stage probability proportional to size (PPS) sample method was performed to sample 2184 from 0.44 million scattered residents in Anxian. On the basis of statistical description, mental health of different characteristics groups was compared.Three main symptoms of posttraumatic stress disorders in 2184 residents (11.23+/-3.44) were higher than the 103 fire victims in Hunan in 2003 (10.06+/-3.26), three factor scores of SCL-90 (5.76+/-1.74) were higher than normal in 1998 repair mode (n=23 891) (4.72+/-1.44), and the statistical difference was observed (t=10.77, P0.05; t=706.04, P0.05). Comparing the mental health of different groups, some significant differences were found by age, gender and education background.The earthquake disaster brought prevalent physical and emotional reaction. Elderly people, female, junior students need mental intervention immediately. Therefore, strengthen the mental education and assistance (especially in high risk groups) would be of more significance.

To explore the public health situation and needs in Anxian after Wenchuan earthquake so as to make an effective strategy for disease control and prevention.69 concentrated settlements with 100 residents were investigated. Probability proportion to size was adopted for sampling of 2200 residents from 687 scattered households (about 440 000 scattered residents). The content of this survey included drinking water, food hygiene, environment sanitation, planning immunity and medical health service, disease surveillance and so on. SPSS 16.0 was used for data analysis, and statistical interpretation was used to describe the results.90.9% (31/66) resettled residents in Anxian lived in tents, 7.6% (5/66) lived in the movable-plate house, 93.3% (621/666) scattered households lived in tents and 71.9% (446/621) of them lived in tents which were built by residents themselves; the rate of drinking water disinfection in resettlement sites and scattered households were 97.1% (66/68) and 94.6% (650/687); 12.8% scattered residents had mouldy or food; 50% of resettlement sites raised animals; 43.6% (17/39) medical station didn't have bacterin inoculation service; 66.7% (10/15) lacked sufficient disinfection equipment; register rate was 50.0% (33/66) and report rate of symptoms and infectious diseases was 56.1% (37/66).There was still some risk of enteric and vector-borne diseases in Anxian, therefore, some tailored measures should be very important.