The nodule-specific transcriptional repressor Top Hub 4 regulates nodule structure and nitrogen fixation capacity in soybean

Most leguminous plants establish symbiotic relationships with rhizobia to form root organs called nodules(Ferguson et al.,2010).Nodules are specialized organs containing bacterial symbionts,which can provide enormous amounts of fixed nitrogen to their plant hosts(Peoples et al.,2009).Soybean(Glycine max),an economically important grain and oil crop,forms symbiotic nitrogen-fixing nodules,which reduces the demand for chemical nitrogen fertilizers and promotes yield(Saito et al.,2014).Nodule development is spatiotemporally regulated by the action of a number of transcription factors(TFs).

Consensus for prevention and management of coronavirus disease 2019 (COVID-19) for neurologists

Coronavirus disease 2019(COVID‐19)has become a pandemic disease globally.Although COVID-19 directly invades lungs,it also involves the nervous system.Therefore,patients with nervous system involvement as the presenting symptoms in the early stage of infection may easily be misdiagnosed and their treatment delayed.They become silent contagious sources or‘virus spreaders’.In order to help neurologists to better understand the occurrence,development and prognosis,we have developed this consensus of prevention and management of COVID‐19.It can also assist other healthcare providers to be familiar with and recognise COVID-19 in their evaluation of patients in the clinic and hospital environment.

Clinical time course of COVID-19, its neurological manifestation and some thoughts on its management

Coronavirus disease-2019(COVID‐19)has become a global pandemic.COVID-19 runs its course in two phases,the initial incubation phase and later clinical symptomatic phase.Patients in the initial incubation phase often have insidious clinical symptoms,but they are still highly contagious.At the later clinical symptomatic phase,the immune system is fully activated and the disease may enter the severe infection stage in this phase.Although many patients are known for their respiratory symptoms,they had neurological symptoms in their first 1-2 days of clinical symptomatic phase,and ischaemic stroke occurred 2 weeks after the onset of the clinical symptomatic phase.The key is to prevent a patient from progressing to this severe infection from mild infection.We are sharing our experience on prevention and management of COVID-19.

Characterization of two constitutive promoters RPS28 and EIF1 for studying soybean growth,development,and symbiotic nodule development

Native promoters that can drive high and stable transgene expression are important tools for modifying plant traits.Although several such promoters have been reported in soybean(Glycine max),few of them function at multiple growth and development stages and during nodule development.Here,we report that the promoters of 40S RIBOSOMAL PROTEIN SMALL SUBUNIT S28(RPS28)and EUKARYOTIC TRANSLATION INITIATION FACTOR 1(EIF1)are ideal for high expression of transgene.Through bioinformatic analysis,we determined that RPS28 and EIF1 were highly expressed during soybean growth and development,nodule development,and various biotic and abiotic stresses.Fusion of both RPS28 and EIF1 promoters,with or without their first intron,with the reporter geneβ-GLUCURONIDASE(uidA)in transgenic soybean,resulted in high GUS activity in seedlings,seeds,and nodules.Fluorimetric GUS assays showed that the RPS28 promoter and the EIF1 promoter yielded high expression,comparable to the soybean Ubiquitin(GmUbi)promoter.RPS28 and EIF1 promoters were also highly expressed in Arabidopsis thaliana and Nicotiana benthamiana.Our results indicate the potential of RPS28 and EIF1 promoters to facilitate future genetic engineering and breeding to improve the quality and yield of soybean,as well as in a wide variety of other plant species.