34 research outputs found
Dynamic Secure Interconnection for Security Enhancement in Cloud Computing
Cloud computing brings efficiency improvement on resource utilization nd other benefits such as on-demand service provisioning, location independence and biquitous access, elastic resource pooling, pay as usage pricing mode, etc. However, t also introduces new security issues because the data management and ownership re separated, and the management is operated on a virtualized platform. In this paper, novel dynamic secure interconnection (DSI) mechanism is proposed to isolate he cloud computing system into a couple of dynamic virtual trust zones with different ecurity policies implemented for different customers so as to enhance security. xperimental results are presented to demonstrate the feasibility and effectiveness of he DSI mechanism
Isolation and Functional Characterization of a Floral Repressor, BcMAF1, From Pak-choi (Brassica rapa ssp. Chinensis)
MADS-box genes form a large gene family in plants and are involved in multiple biological processes, such as flowering. However, the regulation mechanism of MADS-box genes in flowering remains unresolved, especially under short-term cold conditions. In the present study, we isolated BcMAF1, a Pak-choi (Brassica rapa ssp. Chinensis) MADS AFFECTING FLOWERING (MAF), as a floral repressor and functionally characterized BcMAF1 in Arabidopsis and Pak-choi. Subcellular localization and sequence analysis indicated that BcMAF1 was a nuclear protein and contained a conserved MADS-box domain. Expression analysis revealed that BcMAF1 had higher expression levels in leaves, stems, and petals, and could be induced by short-term cold conditions in Pak-choi. Overexpressing BcMAF1 in Arabidopsis showed that BcMAF1 had a negative function in regulating flowering, which was further confirmed by silencing endogenous BcMAF1 in Pak-choi. In addition, qPCR results showed that AtAP3 expression was reduced and AtMAF2 expression was induced in BcMAF1-overexpressing Arabidopsis. Meanwhile, BcAP3 transcript was up-regulated and BcMAF2 transcript was down-regulated in BcMAF1-silencing Pak-choi. Yeast one-hybrid and dual luciferase transient assays showed that BcMAF1 could bind to the promoters of BcAP3 and BcMAF2. These results indicated that BcAP3 and BcMAF2 might be the targets of BcMAF1. Taken together, our results suggested that BcMAF1 could negatively regulate flowering by directly activating BcMAF2 and repressing BcAP3
Genome-Wide Identification and Analysis of <i>ZF-HD</i> Gene Family in Moso Bamboo (<i>Phyllostachys edulis</i>)
Zinc finger-homeodomain (ZF-HD) proteins play essential roles in plant growth, development and stress responses. However, knowledge of the expression and evolutionary history of ZF-HD genes in moso bamboo remains limited. In this study, a total of 24 ZF-HD genes were found unevenly distributed on 12 chromosomes in moso bamboo (Phyllostachys edulis). Phylogenetic analysis indicated that PeZF-HDs were divided into two subfamilies: ZHD and MIF. The ZHD subfamily genes were further classified into seven groups according to their orthologous relationships among the rice and Arabidopsis ZF-HD gene family. The gene structures and conserved motifs of PeZF-HDs were analyzed. Whole-genome duplication (WGD) or segmental duplication promoted the evolution and expansion of the moso bamboo ZF-HD gene family. Ka/Ks ratios suggested that the twenty-four duplication pairs had undergone purifying selection. Promoter analysis showed that most PeZF-HDs contained cis-elements associated with stress responses and hormones. Expression analysis demonstrated that many PeZF-HDs were responsive to abiotic stress treatment. Overall, this work investigated PeZF-HD genes in moso bamboo using bioinformatic approaches. The evolutionary research on gene structure, motif distribution and cis-regulatory elements indicated that PeZF-HDs play distinct roles in biological processes, which provides a theoretical basis for exploring the physiological functions of ZF-HDs and selecting candidate stress-related genes in moso bamboo
Identification, evolution and functional inference on the cold-shock domain protein family in Pak-choi (Brassica rapa ssp. chinensis) and Chinese cabbage (Brassica rapa ssp. pekinensis)
The cold shock domain proteins (CSPs) play important roles in plant developmental processes and stress responses. Multiple sequence alignments found that these CSPs all have a cold shock domain fragment. Phylogenetic tree analysis found that most BcCSPs were more closely related to BrCSPs than other crops. Furthermore, we observed the conserved intron/exon structural patterns of these CSP genes in Pak-choi, Chinese cabbage and Arabidopsis, all motif were observed to be conserved among several boxes subgroups. Comparative analysis of expression patterns of CSP genes in Pak-choi, Chinese cabbage and Arabidopsis suggest that the CSP genes play various roles in plants through qRT-PCR analysis. Further, the CSP expression pattern in different tissues (roots, stems and leaves) of Chinese cabbage was also studied. This study showed that these gene family members might play roles in abiotic stresses responses, and might benefit from their functional characterization and utilization in the resistance engineering of Pak-choi and Chinese cabbage
Identification and Functional Characterization of a Cold-Related Protein, BcHHP5, in Pak-Choi (Brassica rapa ssp. chinensis)
In plants, heptahelical proteins (HHPs) have been shown to respond to a variety of abiotic stresses, including cold stress. Up to the present, the regulation mechanism of HHP5 under low temperature stress remains unclear. In this study, BcHHP5 was isolated from Pak-choi (Brassica rapa ssp. chinensis cv. Suzhouqing). Sequence analysis and phylogenetic analysis indicated that BcHHP5 in Pak-choi is similar to AtHHP5 in Arabidopsis thaliana. Structure analysis showed that the structure of the BcHHP5 protein is relatively stable and highly conservative. Subcellular localization indicated that BcHHP5 was localized on the cell membrane and nuclear membrane. Furthermore, real-time quantitative polymerase chain reaction (RT-qPCR) analysis showed that BcHHP5 was induced to express by cold and other abiotic stresses. In Pak-choi, BcHHP5-silenced assay, inhibiting the action of endogenous BcHHP5, indicated that BcHHP5-silenced might have a negative effect on cold tolerance, which was further confirmed. All of these results indicate that BcHHP5 might play a role in abiotic response. This work can serve as a reference for the functional analysis of other cold-related proteins from Pak-choi in the future
Molecular cloning, characterization and expression analysis of BcHHP3 under abiotic stress in Pak-choi (Brassica rapa ssp. Chinensis)
In this study, BcHHP3 was isolated from Pak-choi; it has an open-reading frame (ORF) of 1044 base pairs, encoding 347 amino acids, a molecular weight of 39.35 kDa, isoelectric point (pI) of 9.08, an instability index of 48.35, and grand average of hydropathicity of 0.382. Multi-alignment and phylogenetic analysis showed that BcHHP3 bears a high similarity to AtHHP2. As predicted by SOMPA and SWISS-MODEL databases, the structure of the BcHHP3 protein is relatively stable and highly conservative. Real-time quantitative polymerase chain reaction (qRT-PCR) analysis showed that BcHHP3 was induced to co-express under cold and abscisic acid (ABA) stresses. The BcHHP3-GFP fusion protein was localized on the cell membrane and nuclear membrane. This work might be useful for future analysis of other HHP-like genes in Pak-choi
Table_1.xlsx
<p>MADS-box genes form a large gene family in plants and are involved in multiple biological processes, such as flowering. However, the regulation mechanism of MADS-box genes in flowering remains unresolved, especially under short-term cold conditions. In the present study, we isolated BcMAF1, a Pak-choi (Brassica rapa ssp. Chinensis) MADS AFFECTING FLOWERING (MAF), as a floral repressor and functionally characterized BcMAF1 in Arabidopsis and Pak-choi. Subcellular localization and sequence analysis indicated that BcMAF1 was a nuclear protein and contained a conserved MADS-box domain. Expression analysis revealed that BcMAF1 had higher expression levels in leaves, stems, and petals, and could be induced by short-term cold conditions in Pak-choi. Overexpressing BcMAF1 in Arabidopsis showed that BcMAF1 had a negative function in regulating flowering, which was further confirmed by silencing endogenous BcMAF1 in Pak-choi. In addition, qPCR results showed that AtAP3 expression was reduced and AtMAF2 expression was induced in BcMAF1-overexpressing Arabidopsis. Meanwhile, BcAP3 transcript was up-regulated and BcMAF2 transcript was down-regulated in BcMAF1-silencing Pak-choi. Yeast one-hybrid and dual luciferase transient assays showed that BcMAF1 could bind to the promoters of BcAP3 and BcMAF2. These results indicated that BcAP3 and BcMAF2 might be the targets of BcMAF1. Taken together, our results suggested that BcMAF1 could negatively regulate flowering by directly activating BcMAF2 and repressing BcAP3.</p
Table_4.xlsx
<p>MADS-box genes form a large gene family in plants and are involved in multiple biological processes, such as flowering. However, the regulation mechanism of MADS-box genes in flowering remains unresolved, especially under short-term cold conditions. In the present study, we isolated BcMAF1, a Pak-choi (Brassica rapa ssp. Chinensis) MADS AFFECTING FLOWERING (MAF), as a floral repressor and functionally characterized BcMAF1 in Arabidopsis and Pak-choi. Subcellular localization and sequence analysis indicated that BcMAF1 was a nuclear protein and contained a conserved MADS-box domain. Expression analysis revealed that BcMAF1 had higher expression levels in leaves, stems, and petals, and could be induced by short-term cold conditions in Pak-choi. Overexpressing BcMAF1 in Arabidopsis showed that BcMAF1 had a negative function in regulating flowering, which was further confirmed by silencing endogenous BcMAF1 in Pak-choi. In addition, qPCR results showed that AtAP3 expression was reduced and AtMAF2 expression was induced in BcMAF1-overexpressing Arabidopsis. Meanwhile, BcAP3 transcript was up-regulated and BcMAF2 transcript was down-regulated in BcMAF1-silencing Pak-choi. Yeast one-hybrid and dual luciferase transient assays showed that BcMAF1 could bind to the promoters of BcAP3 and BcMAF2. These results indicated that BcAP3 and BcMAF2 might be the targets of BcMAF1. Taken together, our results suggested that BcMAF1 could negatively regulate flowering by directly activating BcMAF2 and repressing BcAP3.</p