جستجوی مقالات مرتبط با کلیدواژه « motif » در نشریات گروه « بیوتکنولوژی و ژنتیک گیاهی »

Salinity is one of the most important environmental stresses that disrupt the natural growth of plants. Plant use different mechanisms to cope with stress conditions, such as salinity, in which changes in protein expression is the most important one at molecular level. Changes in protein expression depends on their physicochemical changes such as half- life, stability index, iso-electric point, molecular weight, extinction coefficient etc. Furtermore, identification of motifs, patterns and protein domains make it possible to predict changes in the conformation, structure and proteins functions. In this research was selected a number of changed protein in expression under salinity stress in wheat based on the previous proteomic studies for further was selected bioinformatic analysis. Study Physicochemical properties of proteins by ProtParam software, identification of domains by InterProScan and CDD, identification patters for prediction of post translational modification by ScanProsite, similarity by Blast, alignment of similar proteins for identification of conserved block was performed by T-Coffee. Out of the 25 proteins associated with salinity stress, 20 proteins have a half-life more than 20 hours. The molecular weight of these proteins was varied between 13 to 117 kDa and 15 protein showed instability index of less than 40 and therefore classified as stable proteins. Investigation of proteins using TMHMM and Protscale softwares, it was found that Aquaporins, Plasma membrane intrinsic proteins, Plasma membrane ATPase and Rust resistance kinase Lr10 are highly hydrophobic proteins, whose major structure located inside the membranes. Out of 25 proteins, 8 proteins were selected and analyzed for identification of patterns, domains, structure and function. α-tubulin as a monomer participates with -tubulin to make α-tubulin dimer. Tubulin create a major part of microtubules that are essential for cell growth and division. This protein consisted of one pattern, Tubulin subunits alpha, beta and gamma signature domain namly PLN00221. For the Triosphosphate isomerase protein, a domain called TIM, which is involved in the catalytic mechanism and for the Calmodulin protein a domain called PTZ00184 was identified which is a calcium binding domain. For the Putative glycine decarbixylase subunit a domain called PRK01202 has been identified that has carboxylase activity. For Cu/Zn superoxide dismutase protein the domain called as SOD is involved in the absorption of superoxide. For Fructose-bisphosphate aldolase protein, the catalytic converter domain was identified as PLV02455 and for Hsp 70- Hsp 90 organizing protein, STI1 domain was identified with ATPase property. For the 2- Cys peroxiredoxin BAS 1 protein, for the PRX-Typ 2 cys domain that plays an important role in regulating oxidation- cell reduction.

Zincfinger CCCH (C3HZNF) genes encode proteins with three cysteines and one histidine. The proteins of this family are an important group of zinc finger transcription factors that are effective in various activities such as plant growth and response to biotic and abiotic stresses and actually They are effective in stresses tolarance. In this article, C3HZNF protein data of Arabidopsis and rice plants were used to analyze phylogenetic relationships, exon/intron structure, motifs/domains organization. These studies showed the high homology of these genes with CCCH genes in rice. Analysis of the gene structure showed that AtC3Hs have a variable number of exons, but in general, genes with 1 and 7 exons contain the largest number. study the physical and chemical properties of this family showed that AtC3H36 is the most stable protein among the members of this family, and the highest isoelectric point belongs to the AtC3H7(9.96) protein. The observations showed that the members of this gene family have 1 to 6 Znf C3H domains and a total of 17 functional domains. Phylogeny comparison between C3H proteins in rice and Arabidopsis showed that these proteins are highly conserved. In the comparative phylogenetic analysis of AtC3H and OsC3H, the orthologous genes were placed in one group. For example, OsC3H8 showed close homology to HUA1 in Arabidopsis (AtC3H37), suggesting that this gene is involved in flower development. This study provides valuable information about the important CCCH zinc finger gene family in Arabidopsis and rice. This information can be helpful in understanding how these genes work to help plant tolarance when faced with biotic and abiotic stresses.

Objective DREB gene family is one of the effective transcription factors in plant tolerance to environmental stresses, including salinity stress. The aim of this study is to identify and evaluate the expression of DREB2 gene in different salinity concentrations in local wheat of Kalak Afghan. Materials and methods Salinity stress treatment was applied to wheat using NaCl salt. Experimental treatments included different salinity levels (0, 100, 150, 200, 250 and 300 mM). Then RNA extraction and cDNA synthesis were performed and the specific fragment of DREB2 gene was amplified with specific primers. The obtained transcript was then sent for sequencing and the sequence was analyzed to identify the DREB2 gene. Results Partial sequence of DREB2 gene of local wheat of Kalak Afghani was registered in NCBI database with access number KR106189. The results of sequencing showed that the obtained sequence is more than 95% similar to the sequence of this gene in Triticum dicoccoides and Agropyrum elongatum. Examination of the second structure of DREB2 protein sequence through PSIpred and SOPMA programs showed that this sequence has 46 alpha helices (32.86%), 11 beta helices (7.86%), 9 long strands (6.43%) and 74 is a random helix (52.86%). The results of evaluation of DREB2 gene expression showed that the concentration of 100 mM salinity treatment, has a significant effect on increasing gene expression. In general, the highest effect on DREB2 gene expression was 100 mM salinity treatment and the lowest value was 300 mM. Conclusions In general, the DREB2 gene increases plant tolerance compared to other stress-induced genes, which makes them a desirable target for genetic engineering and crop performance. It seems that the reason that the expression of DREB2 gene does not increase at high concentrations is that the salt load is greater than the cells' ability to transmit it. Under these conditions, salt is transferred to the cytoplasm and inhibits enzymatic activities. Also, a common consequence of the accumulation of high concentrations of salt is the accumulation of large amounts of Reactive oxygen species (ROS), which can cause protein oxidation, damage to cellular DNA, lipid peroxidation, and interaction with other vital cell components. Leads to cell toxicity.

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.

Promoter sequences are one of the key factors in directed gene expression. Different types of promoters can be used according to the type of tissue or expression levels desired. β-Conglycinin is one of the major storage proteins in soybean seed embryos and is produced in the seed development stage. The synthesis of storage proteins is primarily controlled at the transcriptional level and seed-specific expression has been shown to be conferred upon the promoter regions of many storage protein genes. In this research, a seed specific promoter (β-Conglycinin) of Iranian Glycin max was isolated from genomic DNA. Then, the promoter was cloned into pTZ57R/T and sequenced. Sequence analysis showed that the cloned promoter contained all of the typical conserved motifs such as TATA box, CAAT box as well as other previously identified seed-specific motifs such as SKn-1, RY repeats, G box. Finally, the β-Conglycinin promoter was cloned into pBI121 binary vector for further research.