Proteins in the plant apoplast are essential for many physiological processes. We have analysed and compared six different infiltration solutions for proteins contained in the apoplast to recognize the most suitable method for leaves and to establish proteome maps for each extraction. The efficiency of protocols was evaluated by comparing the protein patterns resolved by 1-DE and 2-DE, and revealed distinct characteristics for each infiltration solution. Nano-LC-ESI-Q-TOF MS analysis of all fractions was applied to cover all proteins differentially extracted by infiltration solutions and led to the identification of 328 proteins in total in apoplast preparations. The predicted subcellular protein localisation distinguished the examined infiltration solutions in those with high or low amounts of intracellular protein contaminations, and with high or low quantities of secreted proteins. All tested infiltration solution extracted different subsets of proteins, and those implications on apoplast-specific studies are discussed.

Na + accumulation in the leaf apoplast has been suggested to lead to dehydration, later wilting and finally, the death of the affected leaves. Our aim has been to evaluate whether the reduction in the plant growth of sensitive maize in response to salinity is correlated with higher amounts of Na + and Cl ) concentrations in the leaf apoplast. Subcellular ion patterns in intact leaves were investigated by using deionised water infiltration. We found an increase in soluble Na + and Cl ) concentrations of about 16-and 4-fold, respectively, compared with the control. These concentrations characterized the apoplasts of expanding leaves that had entirely developed under salinity. Interestingly, the K + concentration was significantly reduced by 64 % compared with its control in the symplast under salinity. Our finding of a significantly decreased Ca 2+ concentration in shoots suggested a possible association of Ca 2+ concentration with the reduction in leaf expansion under salinity. As the absolute increase in the apoplastic Na + concentration during salt treatment was much lower compared with the increase in the symplastic Na + concentration, salt treatment in maize appears not to result in osmotic stress imposed by a high apoplastic Na + concentration as has been suggested for other plant species (Oertli hypothesis).

Soil pollution caused by heavy metals is one of the major problems throughout the world. To maintain a safe and healthy environment for human beings, there is a dire need to identify hyperaccumulator plants and the underlying genes involved in heavy metals stress tolerance and accumulation. The goal of this research is to explore the potential of hemp as a decontaminator of heavy metals by identifying the two important heavy metals responsive genes, glutathione-disulfidereductase (GSR) and phospholipase D-a (PLDa). The results revealed heavy metals accumulation; Cu (1530 mg kg ) in hemp plants' leaves collected from the contaminated site. This shows the ability of the hemp plant to tolerate heavy metals, perhaps due to the presence of stress tolerance genes. In this study, partial sequences of putative GSR (215 bp) and PLDa (517 bp) genes were identified, responsive to heavy metals stress in hemp leaves. Both genes exhibited 40-60% sequence identity to previously reported genes from other plant species. Glutathione binding residues and conserved arginine residues were found identical in a putative GSR gene to those of other plant species, while the phospholipids binding domain and catalytic domain were found in the PLDa gene. These results will help to improve our understanding about the phytoremediation potential of hemp as well as in manipulating GSR and PLDa genes in breeding programs to produce transgenic heavy-metals-tolerant varieties.

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Objective Several essential factors have played a crucial role in the spreading mechanism of COVID-19 (Coronavirus disease 2019) in the human population. These factors include undetected cases, asymptomatic cases, and several non-pharmaceutical interventions. Because of the rapid spread of COVID-19 worldwide, understanding the significance of these factors is crucial in determining whether COVID-19 will be eradicated or persist in the population. Hence, in this study, we establish a new mathematical model to predict the spread of COVID-19 considering mentioned factors. Results Infection detection and vaccination have the potential to eradicate COVID-19 from Jakarta. From the sensitivity analysis, we find that rapid testing is crucial in reducing the basic reproduction number when COVID-19 is endemic in the population rather than contact trace. Furthermore, our results indicate that a vaccination strategy has the potential to relax social distancing rules, while maintaining the basic reproduction number at the minimum possible, and also eradicate COVID-19 from the population with a higher vaccination rate. In conclusion, our model proposed a mathematical model that can be used by Jakarta’s government to relax social distancing policy by relying on future COVID-19 vaccine potential.