فهرست مطالب seyyed hamidreza hashemi petroudi

Chitosan (Cs) was extracted from shrimp shell and its derivative forms including N-alkyl (AlkCs) and nanoparticles (CsNPs) were prepared. First, the properties of nanoparticles were determined by dynamic light scattering (DLS) and the morphology of nanoparticles and N-alkylated by scanning electron microscopy (SEM). Then their antibacterial activity was evaluated by the test of minimum inhibitory (MIC) and lethal (MBC) concentration, diffusion on agar by disk, permeability of cell membrane by measurement of cytoplasmic beta-galactosidase release (ONPG). The type of apoptosis cell death was also examined by DAPI staining and changes in cell surface integrity by atomic force microscopy (AFM). The results showed that the nanoparticles are spherical with an average hydrodynamic diameter of 240 nm. N-alkyl had a rough surface structure compared to native chitosan. At the least of MIC (78 μg/ml) and MBC (100 μg/ml) points were observed for CsNPs (P < 0.05). Nanoparticles and N-alkyl of chitosan showed the highest diameter of growth inhibition zone at 1250 concentration compared to other disks (p <0.05). Outer membrane permeability of derivative forms of chitosan showed significant differences with native chitosan and cells of control. DAPI staining test showed higher cell death of chitosan-derived forms. DAPI staining test showed higher cell death of derivative of chitosan. The images obtained from AFM showed a change in the membrane integrity of the treated cells compared to spherical and clustered of control cells. Thus, the antibacterial properties of native chitosan improved by physical and chemical modification.

Calcineurin B-like (CBL) proteins, as calcium sensors, serve roles in plant responses to varied abiotic stressors and in growth and development through interaction with CBL-interacting protein kinases (CIPKs). However, information on the roles and development of CBLs in sweet orange plants is limited. We surveyed the whole Citrus sinensis genome and found eight CBL genes. Domains features, position and distribution, and conserved motif revealed that the EF-hands domain was conserved across the eight CsCBLs. CsCBL proteins are classed as acidic CBL, and five myristoylation sites and six palmitoylation sites were predicted. Eight CsCBLs were distributed across chromosomes Chr01, Chr02, Chr04, and Chr05 and contig chrNW-006257104.1. In chromosome 05, tandem duplications likely gave rise to two CsCBL4 and CsCBL5 genes. The phylogeny tree of 37 CBL proteins from different plant species including Arabidopsis thaliana, Oryza sativa, Sesamum indicum, and C. sinensis showed that these CBLs are closely related. A meta-analysis of the CsCBL gene family's expression in different tissues/stresses revealed that CsCBL genes expressed differently in tissues, which could be evidence for CsCBL tissue/stress-specific expression. The results of this study highlight the functional properties of the CsCBL gene family and provide crucial data for future research on their functional activities.

Calcineurin B-like proteins (CBLs) are a subfamily of calcium sensors that play a role in various plant cell processes and molecular functions. In sesame (Sesamum indicum), in silico analysis of the CBL gene family was performed to identify CBL proteins involved in calcium signaling. Using their orthologic relationships with Arabidopsis homolog genes, the nine SiCBL genes were identified and subdivided into six groups: SiCBL1, SiCBL2, SiCBL3, SiCBL4, SiCBL8, SiCBL10. The molecular weight of SiCBL proteins ranged from 24.4 to 37.9 kDa, the Isoelectric acid pH range, the instability index ranged from 33.99 to 47.46 percent, the aliphatic index ranged from 80.29 to 10.89, and the GRAVY ranged from -0.420 to 0.061. Prediction of post-translational modifications revealed that palmitoylation motif was observed in all siCBL, however majority of them did not have myristoylaton motif. In term of gene structure, 11% of SiCBL genes had nine exons, 11% had eight exons and 77% had seven exons. The RNA-seq pattern of the SiCBL subfamily under PEG treatment revealed that, whereas members of this gene family had generally similar expression patterns in both susceptible and tolerant cultivars, due to functional Convergence, each member of this gene family had a distinct expression pattern. Future research on the expression of SiCBL and SiCIPK gene family genes under various abiotic conditions could aid in understanding the mechanism of expression control of SOS-related genes.

The calcineurin B-like protein (CBL) is an essential calcium sensor that plays a crucial role in plant growth, development and stress responses. The identification of a cis-acting element in the promoter region of the CBL gene family in three plants, including Oryza sativa (OsCBL), Arabidopsis thaliana (AtCBL), and Arabidopsis littoralis (AtCBL), was investigated because of their importance and involvement in signal transduction under abiotic and biological stresses. Sub-cellular localization of 10 AtCBL, 10 OsCBL and six AlCBL genes showed that AtCBL4, AtCBL10, AlCBL4.2, AlCBL4.3 and AlCBL10 proteins were located in the plasma membrane. 26 CBLs were identified and grouped into two major groups based on their orthologous relatedness in the phylogenetic tree. According to a comparative analysis of the gene structure of the CBLs gene family, about 66 percent of AlCBL genes, 60 percent of AtCBL genes, and 80 percent of OsCBL genes had eight exons and seven introns. Cis-regulatory elements were identified and grouped into eight distinct classes. The ABRE, ARE, GC motif, MBS, DRE, STRE, and LTR motifs were essential stress-related elements. Different regulatory mechanisms in the promoter region of AtCBLs are responsible for their distinct expression patterns, which are regulated by numerous tissue-specific and stress-specific cis-elements. The functional analysis of AlCBL4.2 (which contains six as-1 motifs) will provide useful information about this gene's regulatory processes due to its tissue-specific and enhancer feature of as-1 motif.

MicroRNAs are a large class of small and non-coding RNAs that regulate gene expression by binding target mRNA, which leads to cleavage or translational inhibition. Plant miR164 family is highly conserved and is involved in the responses of plants to biotic stresses through the regulation of their target NAC genes. In the present study, 68 putative NAC domain-encoding genes (NACs) were identified in Aeluropus littoralis, a halophyte plant of family Poaceae. Among the AlNAC genes identified, 4 were predicted putative targets for regulation by miR164. The high conservation of miR164 recognition sites in AlNAC genes indicates the essential role of target sites in the normal function of these genes as transcription factors. Expression profile of AlNAC1L.1 candidate gene in response to salt and drought stresses and ABA phytohormone in leaf, stem and root tissues was analyzed by RT-qPCR. The results showed that AlNAC1L.1 gene down-regulated in all tissues at 6 hours after applying stresses. Among the treatments, 600 mM NaCl treatment reduced AlNAC1L.1 expression in leaf, stem and root tissues to about -217, -26 and -9 folds, respectively. Therefore, the AlNAC1L.1 which is ortholog of known Oryza miR164-targeted NAC gene OMTN6, may play negative regulatory role in response to salt, drought and ABA treatments. These results indicated that function of some NAC proteins might be conserved among species. Collectively, these findings provided a useful resource for further analysis of the interactions between NAC genes and their intricate regulation by miR164 in response to abiotic stresses.

Calcium-dependent protein kinase (CPK), as a member of Ser/Thr kinases superfamily, plays a vital role in responding and adapting to biotic and abiotic stresses. The halophyte plant, Aeluropus littoralis, has been considered an attractive model to improve genetic resources of crops and plant stress genomic research. In order to identify the A. littoralis CPK gene family, the whole genome sequences were used to analyze the phylogenetic relationships, exon/intron structure, protein motif/domain organization and the prediction of protein-protein interaction networks. Fourteen AlCPK genes were identified in A. littoralis that were homologous to nine Arabidopsis thaliana CPK genes. The protein domain analysis of AlCPK showed that all studied genes belong to the CPK family due to having several EF-hand (except for AlCPK29.2, which does not have an EF-hand domain) and Kinase domains. AlCPK29.2 protein had the lowest molecular weight and aliphatic index, the highest instability index and gravy among the studied proteins. Gene structure analysis showed that most of AlCPKs (69.8%) have more than seven exons. Besides, AlCPK8 protein was predicted with two N-myristoylation and two palmitoylation motifs, while CPK34.1 protein lacked N-myristoylation, and palmitoylation motif and AlCPK5.1 protein had three palmitoylation motifs. Transcriptome analysis of 34 members of the AtCPK gene family in five abiotic stresses showed that AtCPK genes had diverse expression at different treatments, which could be evidence for AtCPK tissue/ stress-specific expression. The ABF4 gene was identified as one of the components of ABA signaling in AlCPK protein-protein interactions. The findings of this research can be used to classify the roles and pathways of the stress response by studying AlCIPK gene expression under different abiotic stresses.

To evaluate biochemically in different time course in rice mutants (M9) (seedling stage) under NaCl stress, a split factorial experiment was conducted based on randomized complete block design with 3 replications in the greenhouse of Genetics and Agricultural Biotechnology Institute of Tabarestan (GABIT), during 2019. The main factor included sampling time (3, 6 and 9 days after stress) and sub-factors included salinity stress in three levels of NaCl (0, 4 and 8 ds/m (saline water + paddy soil)) and rice genotypes (14 mutants (M9), 2 susceptible controls of Sepidrood, IR29 and 2 controls tolerant of Dailamani, Nonabokra). Then, the yield per plant and STI index were evaluated as factorial. Analysis of variance showed that the main and the interaction effects were significant for all traits at 1% probability level. At the time of sampling (9 days after stress) and salinity of 8ds/m, proline concentration in tolerant genotypes increased and malondialdehyde content in tolerant genotypes decreased. Four genotypes at salinity 8ds/m had higher yield than Dailamani. In these genotypes, increasing proline and decreasing malondialdehyde at higher times increased yield. 4 genotypes showed higher stress tolerance index and 3 genotypes showed lower yield loss than Dailamani. Considering the biochemical properties effective in salinity stress, it is possible to suggest these genotypes (G1, G4 and G8) which at 8ds/m  with yield of 2.36, 2.36 and 2.41 (gr) respectively, compared to Dailamani (1/54 gr) They had higher yields and can be used as promising saline-tolerant lines in saline fields.

Calcineurin B-like proteins (CBLs), which act as a secondary messenger molecule in the subfamily of the calcium sensor gene family, play a key role in regulating physiological processes, plant growth and development. In order to identification and comparison of proteins involving in calcium signaling in two model of halophyte and glycophyte plants, in silico analysis of the CBL gene family were done in Aeluropus littoralis and Arabidopsis thaliana. Based on sequence homology and orthological relationships with Arabidopsis genes, 6 genes identified in Aeluropus were classified into three protein groups: AlCBL4, AlCBL2 and AlCBL10. Multiple sequence allignment of the CBL gene family in Aeluropus littoralis confirmed the presence of four EF-hand domains in all genes, which provide a structure for calcium ion binding. The high similarity of the physicochemical properties of most Aeluropus proteins to Arabidopsis as well as the strong orthological relationship with each other may indicate the preservation of the function of these genes in the evolutionary process. Analysis of AtCBLs expression patterns in different organs/ abiotic stresses showed that these genes have unique expression profiles due to functional and structural convergent. Different expression profiles of AlCBLs in Aeluropus transcriptome would be an evidence for the functional divergent of these genes. The results obtained from this study can provide valuable information about the properties of this gene family and their functional roles in tolerating to abiotic stresses for future studies.

In this study, the type and frequency of regulatory elements in the promoter regions of DVL gene family in Aeluropus littoralis were studied. Relative expression of AlDVL8 gene as a member of this family was also measured under the salinity stress, salicylic acid, gibberellic acid and cytokinin. The results of the promoter study indicated that, this gene family has different regulatory elements for responding to stresses and hormones. Some of these regulatory elements are present in the promoter region of all genes, possibly indicating the general role of DVLs. Some others are present only in the promoter region of some genes that may be related to their specific activity. Treatments other than cytokinin increased gene expression in the shoot at 3, 12, and 24 hours and decreased expression at 6 hours. Cytokinin treatment at all times increased gene expression. In the root, almost the reverse trend of gene expression was observed, so that at 6 hours, increased gene expression was observed in all treatments, and at 12 and 24 hours, decreased expression was observed in all treatments. The results of this study showed that the expression of AlDVL8 gene in shoot and root organs was induced by experimental treatments and its expression was inverse in these two different tissues. Due to the changes in hormones during stress, expression induction of this gene family, and the presence of stress-responsive elements in the promoter regions of these genes, this gene family can be suggested as a candidate for stress tolerance.

Dehydrins (DNHs) belong to group II of LEA (Late Embryogenesis Abundant) protein family which are expressed in late embryogenesis and accumulate in vegetative tissues in response to multiple abiotic stresses such as salt, drought and cold stress These proteins could be classified to five subgroups (YnSKn, Kn, SKn, KnS, and YnKn) based on the sequence and number of K, S, and Y segments. In this study, 5 genes encoding dehydrin protein (DHN) were identified in Aeluropus littoralis, genome as a halophyte grass, belonging to the Poaceae family and physicochemical characteristics, cell localization, conserved motifs and gene structure were determined and evolutionary relationships among different species were considered. AlDHN proteins were classified in the YnSKn subgroup based on highly conserved domains. The expression pattern of AlDHN.5 gene as a homologue of RAB18 (AT5G66400) gene was examined in both leaf and root tissues under salinity, drought, cold stresses and abscisic acid treatment. Analysis of the expression pattern of this gene in both leaf and root tissues showed that this gene is more expressed in leaf tissue compared to root under drought, cold stresses and ABA treatment. Current study lays the foundation for further studies into the regulation of their expression under various environmental conditions.

Salt stress is one of the abiotic stresses limiting plant growth and development. The ethylene response factor (ERF) is one of the transcription factor family that involved in plant development and responses to biotic and abiotic stresses. Regarding to importance role of genes belonging to ERF gene family in plant responses to salt stress, identification of these genes in the Aeluropus littoralis, halophyte plant, was considered in this study. In total, 36 non-redundant ERF genes were identified in A. littoralis genome. The phylogenetic tree classified the AlERF gene family into six distinct groups (B1 to B6) based on hemology with the Araboidopsis thaliana. Gene structure analysis revealed that AlERF genes contained zero to two introns. Domain search and conserved motif analyses in AlERF protein sequences determined that 2 motifs (1 and 2) out of the identified 10 motifs participate in the AP2/ERF domain structure. Based on transcriptome data and heatmap diagram, AlERF6.3 gene was expressed more in root tissue under salinity stress, and the least expression level was observed in AlERF6.7 gene in leaf tissue under recovery conditions. The different expression patterns of genes in leaf and root tissues under salt stress suggested different regulatory mechanisms in the gene expression. The results of this study, as the first report on the ERF gene family in A. littoralis, provides basic information for further studies of the functional characteristics of AlERF genes.