Displaying publications 21 - 40 of 148 in total

Abstract:
Sort:
  1. HnRNP-like proteins as post-transcriptional regulators
    Yeap WC, Namasivayam P, Ho CL
    Plant Sci, 2014 Oct;227:90-100.
    PMID: 25219311 DOI: 10.1016/j.plantsci.2014.07.005
    Plant cells contain a diverse repertoire of RNA-binding proteins (RBPs) that coordinate a network of post-transcriptional regulation. RBPs govern diverse developmental processes by modulating the gene expression of specific transcripts. Recent gene annotation and RNA sequencing clearly showed that heterogeneous nuclear ribonucleoprotein (hnRNP)-like proteins which form a family of RBPs, are also expressed in higher plants and serve specific plant functions. In addition to their involvement in post-transcriptional regulation from mRNA capping to translation, they are also involved in telomere regulation, gene silencing and regulation in chloroplast. Here, we review the involvement of plant hnRNP-like proteins in post-transcription regulation of RNA processes and their functional roles in control of plant developmental processes especially plant-specific functions including flowering, chloroplastic-specific mRNA regulation, long-distance phloem transportation and plant responses to environmental stresses.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  2. Fulltext DNA methylation and expression of the EgDEF1 gene and neighboring retrotransposons in mantled somaclonal variants of oil palm
    Jaligot E, Hooi WY, Debladis E, Richaud F, Beulé T, Collin M, et al.
    PLoS One, 2014;9(3):e91896.
    PMID: 24638102 DOI: 10.1371/journal.pone.0091896
    The mantled floral phenotype of oil palm (Elaeis guineensis) affects somatic embryogenesis-derived individuals and is morphologically similar to mutants defective in the B-class MADS-box genes. This somaclonal variation has been previously demonstrated to be associated to a significant deficit in genome-wide DNA methylation. In order to elucidate the possible role of DNA methylation in the transcriptional regulation of EgDEF1, the APETALA3 ortholog of oil palm, we studied this epigenetic mark within the gene in parallel with transcript accumulation in both normal and mantled developing inflorescences. We also examined the methylation and expression of two neighboring retrotransposons that might interfere with EgDEF1 regulation. We show that the EgDEF1 gene is essentially unmethylated and that its methylation pattern does not change with the floral phenotype whereas expression is dramatically different, ruling out a direct implication of DNA methylation in the regulation of this gene. Also, we find that both the gypsy element inserted within an intron of the EgDEF1 gene and the copia element located upstream from the promoter are heavily methylated and show little or no expression. Interestingly, we identify a shorter, alternative transcript produced by EgDEF1 and characterize its accumulation with respect to its full-length counterpart. We demonstrate that, depending on the floral phenotype, the respective proportions of these two transcripts change differently during inflorescence development. We discuss the possible phenotypical consequences of this alternative splicing and the new questions it raises in the search for the molecular mechanisms underlying the mantled phenotype in the oil palm.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  3. Fulltext Potential regulatory role of gibberellic and humic acids in sprouting of Chlorophytum borivilianum tubers
    Nakasha JJ, Sinniah UR, Puteh A, Hassan SA
    ScientificWorldJournal, 2014;2014:168950.
    PMID: 24688363 DOI: 10.1155/2014/168950
    Tubers of safed musli (Chlorophytum borivilianum) were immersed in three different concentrations of gibberellic acid (GA3) or humic acid (HA) prior to planting. The highest concentration of GA3 (20 mg L(-1)) and all concentrations of HA (5, 10, and 15%) appeared to hasten tuber sprouting and promote uniform sprouting pattern. The use of 20 mg L(-1) GA3 or 15% HA successfully improved sprouting and mean sprouting time. Safed musli growth and development was improved through the increase in the number of leaves, total leaf area, leaf area index, and total fibrous root length. This directly influenced the number of new tubers formed. The use of 20 mg L(-1) GA3 or 15% HA gave similar response with nonsignificant difference among them. However, due to the cost of production, the result from this study suggests that 15% HA should be used to obtain improved sprouting percentage, homogeneous stand establishment, efficient plant growth and development, and increased yield of safed musli.
    Matched MeSH terms: Gene Expression Regulation, Plant/physiology*
  4. Fulltext Drought tolerance in wheat
    Nezhadahmadi A, Prodhan ZH, Faruq G
    ScientificWorldJournal, 2013;2013:610721.
    PMID: 24319376 DOI: 10.1155/2013/610721
    Drought is one of the most important phenomena which limit crops' production and yield. Crops demonstrate various morphological, physiological, biochemical, and molecular responses to tackle drought stress. Plants' vegetative and reproductive stages are intensively influenced by drought stress. Drought tolerance is a complicated trait which is controlled by polygenes and their expressions are influenced by various environmental elements. This means that breeding for this trait is so difficult and new molecular methods such as molecular markers, quantitative trait loci (QTL) mapping strategies, and expression patterns of genes should be applied to produce drought tolerant genotypes. In wheat, there are several genes which are responsible for drought stress tolerance and produce different types of enzymes and proteins for instance, late embryogenesis abundant (lea), responsive to abscisic acid (Rab), rubisco, helicase, proline, glutathione-S-transferase (GST), and carbohydrates during drought stress. This review paper has concentrated on the study of water limitation and its effects on morphological, physiological, biochemical, and molecular responses of wheat with the possible losses caused by drought stress.
    Matched MeSH terms: Gene Expression Regulation, Plant/physiology*
  5. Fulltext Differential Gene Expression Reflects Morphological Characteristics and Physiological Processes in Rice Immunity against Blast Pathogen Magnaporthe oryzae
    Azizi P, Rafii MY, Mahmood M, Abdullah SN, Hanafi MM, Nejat N, et al.
    PLoS One, 2015;10(5):e0126188.
    PMID: 26001124 DOI: 10.1371/journal.pone.0126188
    The rice blast fungus Magnaporthe oryzae is a serious pathogen that jeopardises the world's most important food-security crop. Ten common Malaysian rice varieties were examined for their morphological, physiological and genomic responses to this rice blast pathogen. qPCR quantification was used to assess the growth of the pathogen population in resistant and susceptible rice varieties. The chlorophyll content and photosynthesis were also measured to further understand the disruptive effects that M. oryzae has on infected plants of these varieties. Real-time PCR was used to explore the differential expression of eight blast resistance genes among the ten local varieties. Blast disease has destructive effects on the growth of rice, and the findings of our study provide evidence that the Pikh, Pi9, Pi21, and Osw45 genes are involved in defence responses in the leaves of Malaysian rice at 31 h after inoculation with M. oryzae pathotype P7.2. Both the chlorophyll content and photosynthesis were reduced, but the levels of Pikh gene expression remained constant in susceptible varieties, with a developed pathogen population and mild or severe symptoms. The Pi9, Pi21, and Osw45 genes, however, were simultaneously upregulated in infected rice plants. Therefore, the presence of the Pikh, Pi9, Pi21, and Osw45 genes in the germplasm is useful for improving the resistance of rice varieties.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  6. A Rhythmic Gene Entrained to Midnight May Regulate Photoperiod-Controlled Flowering in Arabidopsis
    Yeang HY
    Yale J Biol Med, 2019 06;92(2):213-223.
    PMID: 31249482
    The widely held explanation for photoperiod-controlled flowering in long-day plants is largely embodied in the External Coincidence Hypothesis which posits that flowering is induced when activity of a rhythmic gene that regulates it (a putative "flowering gene") occurs in the presence of light. Nevertheless, re-examination of the Arabidopsis flowering data from non 24-hour cycles of Roden et al. suggests that External Coincidence is not tenable if the circadian rhythm of the "flowering gene" were entrained to sunrise as commonly accepted. On the other hand, the hypothesis is supported if circadian cycling of the gene conforms to a solar rhythm, and its entrainment is to midnight on the solar clock. Data available point to flowering being induced by the gene which peaks in its expression between 16 to 19 h after midnight. In the normal 24 h cycle, that would be between 4 p.m. and 7 p.m., regardless of the photoperiod. Such timing of the "flowering gene" expression allows for variable coincidence between gene activity and light, depending on the photoperiod and cycle period. A correlation is found between earliness of flowering and the degree of coincidence of "flowering gene" expression with light (r = 0.88, p<0.01).
    Matched MeSH terms: Gene Expression Regulation, Plant/radiation effects
  7. Changes of alternative splicing in Arabidopsis thaliana grown under different CO2 concentrations
    Huang W, Chen X, Guan Q, Zhong Z, Ma J, Yang B, et al.
    Gene, 2019 Mar 20;689:43-50.
    PMID: 30528270 DOI: 10.1016/j.gene.2018.11.083
    Atmospheric CO2 level is one of the most important factors which affect plant growth and crop production. Although many crucial genes and pathways have been identified in response to atmospheric CO2 changes, the integrated and precise mechanisms of plant CO2 response are not well understood. Alternative splicing (AS) is an important gene regulation process that affects many biological processes in plants. However, the AS pattern changes in plants in response to elevated CO2 levels have not yet been investigated. Here, we used RNA-Seq data of Arabidopsis thaliana grown under different CO2 concentration to analyze the global changes in AS. We found that AS increased with the rise in CO2 concentration. Additionally, we identified 345 differentially expressed (DE) genes and 251 differentially alternative splicing (DAS) genes under the elevated CO2 condition. Moreover, the results showed that the expression of most of the DAS genes did not change significantly, indicating that AS can serve as an independent mechanism for gene regulation in response to elevated CO2. Furthermore, our analysis of function categories revealed that the DAS genes were associated mainly with the stimulus response. Overall, this the first study to explore the changes of AS in plants in response to elevated CO2.
    Matched MeSH terms: Gene Expression Regulation, Plant/drug effects
  8. Fulltext Regulation of terpenoid biosynthesis by miRNA in Persicaria minor induced by Fusarium oxysporum
    Samad AFA, Rahnamaie-Tajadod R, Sajad M, Jani J, Murad AMA, Noor NM, et al.
    BMC Genomics, 2019 07 16;20(1):586.
    PMID: 31311515 DOI: 10.1186/s12864-019-5954-0
    BACKGROUND: Persicaria minor (kesum) is an herbaceous plant with a high level of secondary metabolite compounds, particularly terpenoids. These terpenoid compounds have well-established roles in the pharmaceutical and food industries. Although the terpenoids of P. minor have been studied thoroughly, the involvement of microRNA (miRNA) in terpenoid regulation remains poorly understood and needs to be explored. In this study, P. minor plants were inoculated with the pathogenic fungus Fusarium oxysporum for terpenoid induction.

    RESULT: SPME GC-MS analysis showed the highest terpenoid accumulation on the 6th day post-inoculation (dpi) compared to the other treatment time points (0 dpi, 3 dpi, and 9 dpi). Among the increased terpenoid compounds, α-cedrene, valencene and β-bisabolene were prominent. P. minor inoculated for 6 days was selected for miRNA library construction using next generation sequencing. Differential gene expression analysis showed that 58 miRNAs belonging to 30 families had significantly altered regulation.
    Among these 58 differentially expressed genes (DEGs), 27 [corrected] miRNAs were upregulated, whereas 31 [corrected] miRNAs were downregulated. Two putative novel pre-miRNAs were identified and validated through reverse transcriptase PCR. Prediction of target transcripts potentially involved in the mevalonate pathway (MVA) was carried out by psRobot software, resulting in four miRNAs: pmi-miR530, pmi-miR6173, pmi-miR6300 and a novel miRNA, pmi-Nov_13. In addition, two miRNAs, miR396a and miR398f/g, were predicted to have their target transcripts in the non-mevalonate pathway (MEP). In addition, a novel miRNA, pmi-Nov_12, was identified to have a target gene involved in green leaf volatile (GLV) biosynthesis. RT-qPCR analysis showed that pmi-miR6173, pmi-miR6300 and pmi-nov_13 were downregulated, while miR396a and miR398f/g were upregulated. Pmi-miR530 showed upregulation at 9 dpi, and dynamic expression was observed for pmi-nov_12. Pmi-6300 and pmi-miR396a cleavage sites were detected through degradome sequence analysis. Furthermore, the relationship between miRNA metabolites and mRNA metabolites was validated using correlation analysis.

    CONCLUSION: Our findings suggest that six studied miRNAs post-transcriptionally regulate terpenoid biosynthesis in P. minor. This regulatory behaviour of miRNAs has potential as a genetic tool to regulate terpenoid biosynthesis in P. minor.

    Matched MeSH terms: Gene Expression Regulation, Plant*
  9. Fulltext Circadian Rhythms in Legumes: What Do We Know and What Else Should We Explore?
    Kugan HM, Rejab NA, Sahruzaini NA, Harikrishna JA, Baisakh N, Cheng A
    Int J Mol Sci, 2021 Apr 27;22(9).
    PMID: 33925559 DOI: 10.3390/ijms22094588
    The natural timing devices of organisms, commonly known as biological clocks, are composed of specific complex folding molecules that interact to regulate the circadian rhythms. Circadian rhythms, the changes or processes that follow a 24-h light-dark cycle, while endogenously programmed, are also influenced by environmental factors, especially in sessile organisms such as plants, which can impact ecosystems and crop productivity. Current knowledge of plant clocks emanates primarily from research on Arabidopsis, which identified the main components of the circadian gene regulation network. Nonetheless, there remain critical knowledge gaps related to the molecular components of circadian rhythms in important crop groups, including the nitrogen-fixing legumes. Additionally, little is known about the synergies and trade-offs between environmental factors and circadian rhythm regulation, especially how these interactions fine-tune the physiological adaptations of the current and future crops in a rapidly changing world. This review highlights what is known so far about the circadian rhythms in legumes, which include major as well as potential future pulse crops that are packed with nutrients, particularly protein. Based on existing literature, this review also identifies the knowledge gaps that should be addressed to build a sustainable food future with the reputed "poor man's meat".
    Matched MeSH terms: Gene Expression Regulation, Plant/genetics
  10. Fulltext Identification and Analysis of microRNAs in Chlorella sorokiniana Using High-Throughput Sequencing
    Azaman SNA, Satharasinghe DA, Tan SW, Nagao N, Yusoff FM, Yeap SK
    Genes (Basel), 2020 09 25;11(10).
    PMID: 32992970 DOI: 10.3390/genes11101131
    Chlorella is a popular microalga with robust physiological and biochemical characteristics, which can be cultured under various conditions. The exploration of the small RNA content of Chlorella could improve strategies for the enhancement of metabolite production from this microalga. In this study, stress was introduced to the Chlorella sorokiniana culture to produce high-value metabolites such as carotenoids and phenolic content. The small RNA transcriptome of C. sorokiniana was sequenced, focusing on microRNA (miRNA) content. From the analysis, 98 miRNAs were identified in cultures subjected to normal and stress conditions. The functional analysis result showed that the miRNA targets found were most often involved in the biosynthesis of secondary metabolites, followed by protein metabolism, cell cycle, and porphyrin and chlorophyll metabolism. Furthermore, the biosynthesis of secondary metabolites such as carotenoids, terpenoids, and lipids was found mostly in stress conditions. These results may help to improve our understanding of regulatory mechanisms of miRNA in the biological and metabolic process of Chlorella species. It is important and timely to determine the true potential of this microalga species and to support the potential for genetic engineering of microalgae as they receive increasing focus for their development as an alternative source of biofuel, food, and health supplements.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  11. Identification and expression profiling of genes governing lignin biosynthesis in Casuarina equisetifolia L
    Vikashini B, Shanthi A, Ghosh Dasgupta M
    Gene, 2018 Nov 15;676:37-46.
    PMID: 30201104 DOI: 10.1016/j.gene.2018.07.012
    Casuarina equisetifolia L. is an important multi-purpose, fast growing and widely planted tree species native to tropical and subtropical coastlines of Australia, Southeast Asia, Malaysia, Melanesia, Polynesia and New Caledonia. It is a nitrogen-fixing tree mainly used for charcoal making, construction poles, landscaping, timber, pulp, firewood, windbreaks, shelterbelts, soil erosion and sand dune stabilization. Casuarina wood is presently used for paper and pulp production. Raw material with reduced lignin is highly preferred to increase the pulp yield. Hence, understanding the molecular regulation of wood formation in this tree species is vital for selecting industrially suitable phenotypes for breeding programs. The lignin biosynthetic pathway has been extensively studied in tree species like Eucalypts, poplars, pines, Picea, Betula and Acacia sp. However, studies on wood formation at molecular level is presently lacking in casuarinas. Hence, in the present study, the transcriptome of the developing secondary tissues of 15 years old Casuarina equiseitfolia subsp. equisetifolia was sequenced, de novo assembled, annotated and mapped to functional pathways. Transcriptome sequencing generated a total of 26,985 transcripts mapped to 31 pathways. Mining of the annotated data identified nine genes involved in lignin biosynthesis pathway and relative expression of the transcripts in four tissues including scale-like leaves, needle-like brachlets, wood and root were documented. The expression of CeCCR1 and CeF5H were found to be significantly high in wood tissues, while maximum expression of CeHCT was documented in stem. Additionally, CeTUBA and CeH2A were identified as the most stable reference transcript for normalization of qRT-PCR data in C. equisetifolia. The present study is the first wood genomic resource in C. equisetifolia, which will be valuable for functional genomics research in this genus.
    Matched MeSH terms: Gene Expression Regulation, Plant/genetics
  12. Differential expression of heat shock and floral regulatory genes in pseudocarpel initials of mantled female inflorescences from Elaeis guineensis Jacq
    Ooi SE, Sarpan N, Abdul Aziz N, Nuraziyan A, Ong-Abdullah M
    Plant Reprod, 2019 06;32(2):167-179.
    PMID: 30467592 DOI: 10.1007/s00497-018-0350-5
    KEY MESSAGE: Transcriptomes generated by laser capture microdissected abnormal staminodes revealed adoption of carpel programming during organ initiation with decreased expression of numerousHSPs,EgDEF1, EgGLO1but increasedLEAFYexpression. The abnormal mantled phenotype in oil palm involves a feminization of the male staminodes into pseudocarpels in pistillate inflorescences. Previous studies on oil palm flowering utilized entire inflorescences or spikelets, which comprised not only the male and female floral organs, but the surrounding tissues as well. Laser capture microdissection coupled with RNA sequencing was conducted to investigate the specific transcriptomes of male and female floral organs from normal and mantled female inflorescences. A higher number of differentially expressed genes (DEGs) were identified in abnormal versus normal male organs compared with abnormal versus normal female organs. In addition, the abnormal male organ transcriptome closely mimics the transcriptome of abnormal female organ. While the transcriptome of abnormal female organ was relatively similar to the normal female organ, a substantial amount of female DEGs encode HEAT SHOCK PROTEIN genes (HSPs). A similar high amount (20%) of male DEGs encode HSPs as well. As these genes exhibited decreased expression in abnormal floral organs, mantled floral organ development may be associated with lower stress indicators. Stamen identity genes EgDEF1 and EgGLO1 were the main floral regulatory genes with decreased expression in abnormal male organs or pseudocarpel initials. Expression of several floral transcription factors was elevated in pseudocarpel initials, notably LEAFY, FIL and DL orthologs, substantiating the carpel specification programming of abnormal staminodes. Specific transcriptomes thus obtained through this approach revealed a host of differentially regulated genes in pseudocarpel initials compared to normal male staminodes.
    Matched MeSH terms: Gene Expression Regulation, Plant/genetics*
  13. Arabidopsis Group IIId ERF proteins positively regulate primary cell wall-type CESA genes
    Saelim L, Akiyoshi N, Tan TT, Ihara A, Yamaguchi M, Hirano K, et al.
    J Plant Res, 2019 Jan;132(1):117-129.
    PMID: 30478480 DOI: 10.1007/s10265-018-1074-1
    The cell wall determines morphology and the environmental responses of plant cells. The primary cell wall (PCW) is produced during cell division and expansion, determining the cell shape and volume. After cell expansion, specific types of plant cells produce a lignified wall, known as a secondary cell wall (SCW). We functionally analyzed Group IIId Arabidopsis AP2/EREBP genes, namely ERF34, ERF35, ERF38, and ERF39, which are homologs of a rice ERF gene previously proposed to be related to SCW biosynthesis. Expression analysis revealed that these four genes are expressed in regions related to cell division and/or cell differentiation in seedlings (i.e., shoot apical meristems, the primordia of leaves and lateral roots, trichomes, and central cylinder of primary roots) and flowers (i.e., vascular tissues of floral organs and replums and/or valve margins of pistils). Overexpression of ERF genes significantly upregulated PCW-type, but not SCW-type, CESA genes encoding cellulose synthase catalytic subunits in Arabidopsis seedlings. Transient co-expression reporter analysis indicated that ERF35, ERF38, and ERF39 possess transcriptional activator activity, and that ERF34, ERF35, ERF38, and ERF39 upregulated the promoter activity of CESA1, a PCW-type CESA gene, through the DRECRTCOREAT elements, the core cis-acting elements known to be recognized by AP2/ERF proteins. Together, our findings show that Group IIId ERF genes are positive transcriptional regulators of PCW-type CESA genes in Arabidopsis and are possibly involved in modulating cellulose biosynthesis in response to developmental requirements and environmental stimuli.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  14. Characterization of Oil Palm Acyl-CoA-Binding Proteins and Correlation of Their Gene Expression with Oil Synthesis
    Amiruddin N, Chan PL, Azizi N, Morris PE, Chan KL, Ong PW, et al.
    Plant Cell Physiol, 2020 Apr 01;61(4):735-747.
    PMID: 31883014 DOI: 10.1093/pcp/pcz237
    Acyl-CoA-binding proteins (ACBPs) are involved in binding and trafficking acyl-CoA esters in eukaryotic cells. ACBPs contain a well-conserved acyl-CoA-binding domain. Their various functions have been characterized in the model plant Arabidopsis and, to a lesser extent, in rice. In this study, genome-wide detection and expression analysis of ACBPs were performed on Elaeis guineensis (oil palm), the most important oil crop in the world. Seven E. guineensis ACBPs were identified and classified into four groups according to their deduced amino acid domain organization. Phylogenetic analysis showed conservation of this family with other higher plants. All seven EgACBPs were expressed in most tissues while their differential expression suggests various functions in specific tissues. For example, EgACBP3 had high expression in inflorescences and stalks while EgACBP1 showed strong expression in leaves. Because of the importance of E. guineensis as an oil crop, expression of EgACBPs was specifically examined during fruit development. EgACBP3 showed high expression throughout mesocarp development, while EgACBP1 had enhanced expression during rapid oil synthesis. In endosperm, both EgACBP1 and EgACBP3 exhibited increased expression during seed development. These results provide important information for further investigations on the biological functions of EgACBPs in various tissues and, in particular, their roles in oil synthesis.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  15. Effects of acute salt stress on modulation of gene expression in a Malaysian salt-tolerant indigenous rice variety, Bajong
    Yeo BPH, Bhave M, Hwang SS
    J Plant Res, 2018 Jan;131(1):191-202.
    PMID: 28921169 DOI: 10.1007/s10265-017-0977-6
    The small genome size of rice relative to wheat and barley, together with its salt sensitivity, make it an ideal candidate for studies of salt stress response. Transcriptomics has emerged as a powerful technique to study salinity responses in many crop species. By identifying a large number of differentially expressed genes (DEGs) simultaneously after the stress induction, it can provide crucial insight into the immediate responses towards the stressor. In this study, a Malaysian salt-tolerant indigenous rice variety named Bajong and one commercial rice variety named MR219 were investigated for their performance in plant growth and ion accumulation properties after salt stress treatment. Bajong was further investigated for the changes in leaf's transcriptome after 6 h of stress treatment using 100 mM NaCl. Based on the results obtained, Bajong is found to be significantly more salt tolerant than MR219, showing better growth and a lower sodium ion accumulation after the stress treatment. Additionally, Bajong was analysed by transcriptomic sequencing, generating a total of 130 millions reads. The reads were assembled into de novo transcriptome and each transcript was annotated using several pre-existing databases. The transcriptomes of control and salt-stressed samples were then compared, leading to the discovery of 4096 DEGs. Based on the functional annotation results obtained, the enrichment factor of each functional group in DEGs was calculated in relation to the total reads obtained. It was found that the group with the highest gene modulation was involved in the secondary metabolite biosynthesis of plants, with approximately 2.5% increase in relation to the total reads obtained. This suggests an extensive transcriptional reprogramming of the secondary metabolic pathways after stress induction, which could be directly responsible for the salt tolerance capability of Bajong.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  16. Functional characterization of the MSP-C6 promoter as a potential tool for mesocarp-preferential expression of transgenes
    Badai SS, Rasid OA, Masani MYA, Chan KL, Chan PL, Shaharuddin NA, et al.
    J Plant Physiol, 2023 Oct;289:154080.
    PMID: 37699261 DOI: 10.1016/j.jplph.2023.154080
    Modification of lipid composition in the mesocarp tissue of oil palm involves genetic manipulation of multiple genes. More than one mesocarp-preferential promoter is necessary for the expression of individual transgenes in the same plant to obviate transcriptional gene silencing. This study aimed to identify genes that are preferentially expressed in the mesocarp tissue and characterize selected candidate mesocarp-preferential promoters. Ten transcripts that were preferentially expressed in the mesocarp tissue were identified from the analysis of 82 transcriptome datasets of 12 different oil palm tissues. The expression of two candidate genes, MSP-C1 and MSP-C6, was verified to be preferentially expressed in the mesocarp tissues and shown to have a low expression level in non-mesocarp tissues by reverse transcription quantitative real-time PCR (RT-qPCR). MSP-C6 promoter fragments of different lengths were transformed into tomato plants for further characterization. Both unripe and ripe fruits of transgenic tomato plants transformed with a construct harboring the MSP-C6-F1 (2014 bp) promoter were shown to have high beta-glucuronidase (GUS) activities. The findings of this study suggest the potential applications of the MSP-C6 promoter as a molecular tool for genetic engineering of novel traits in fruit crops.
    Matched MeSH terms: Gene Expression Regulation, Plant/genetics
  17. Fulltext Genetic and Global Epigenetic Modification, Which Determines the Phenotype of Transgenic Rice?
    Fan X, Chen J, Wu Y, Teo C, Xu G, Fan X
    Int J Mol Sci, 2020 Mar 06;21(5).
    PMID: 32155767 DOI: 10.3390/ijms21051819
    Transgenic technologies have been applied to a wide range of biological research. However, information on the potential epigenetic effects of transgenic technology is still lacking. Here, we show that the transgenic process can simultaneously induce both genetic and epigenetic changes in rice. We analyzed genetic, epigenetic, and phenotypic changes in plants subjected to tissue culture regeneration, using transgenic lines expressing the same coding sequence from two different promoters in transgenic lines of two rice cultivars: Wuyunjing7 (WYJ7) and Nipponbare (NP). We determined the expression of OsNAR2.1 in two overexpression lines generated from the two cultivars, and in the RNA interference (RNAi) OsNAR2.1 line in NP. DNA methylation analyses were performed on wild-type cultivars (WYJ7 and NP), regenerated lines (CK, T0 plants), segregation-derived wild-type from pOsNAR2.1-OsNAR2.1 (SDWT), pOsNAR2.1-OsNAR2.1, pUbi-OsNAR2.1, and RNAi lines. Interestingly, we observed global methylation decreased in the T0 regenerated line of WYJ7 (CK-WJY7) and pOsNAR2.1-OsNAR2.1 lines but increased in pUbi-OsNAR2.1 and RNAi lines of NP. Furthermore, the methylation pattern in SDWT returned to the WYJ7 level after four generations. Phenotypic changes were detected in all the generated lines except for SDWT. Global methylation was found to decrease by 13% in pOsNAR2.1-OsNAR2.1 with an increase in plant height of 4.69% compared with WYJ7, and increased by 18% in pUbi-OsNAR2.1 with an increase of 17.36% in plant height compared with NP. This suggests an absence of a necessary link between global methylation and the phenotype of transgenic plants with OsNAR2.1 gene over-expression. However, epigenetic changes can influence phenotype during tissue culture, as seen in the massive methylation in CK-WYJ7, T0 regenerated lines, resulting in decreased plant height compared with the wild-type, in the absence of a transformed gene. We conclude that in the transgenic lines the phenotype is mainly determined by the nature and function of the transgene after four generations of transformation, while the global epigenetic modification is dependent on the genetic background. Our research suggests an innovative insight in explaining the reason behind the occurrence of transgenic plants with random and undesirable phenotypes.
    Matched MeSH terms: Gene Expression Regulation, Plant*
  18. The oil palm metallothionein promoter contains a novel AGTTAGG motif conferring its fruit-specific expression and is inducible by abiotic factors
    Omidvar V, Abdullah SN, Izadfard A, Ho CL, Mahmood M
    Planta, 2010 Sep;232(4):925-36.
    PMID: 20635097 DOI: 10.1007/s00425-010-1220-z
    The 1,053-bp promoter of the oil palm metallothionein gene (so-called MSP1) and its 5' deletions were fused to the GUS reporter gene, and analysed in transiently transformed oil palm tissues. The full length promoter showed sevenfold higher activity in the mesocarp than in leaves and 1.5-fold more activity than the CaMV35S promoter in the mesocarp. The 1,053-bp region containing the 5' untranslated region (UTR) gave the highest activity in the mesocarp, while the 148-bp region was required for minimal promoter activity. Two positive regulatory regions were identified at nucleotides (nt) -953 to -619 and -420 to -256 regions. Fine-tune deletion of the -619 to -420 nt region led to the identification of a 21-bp negative regulatory sequence in the -598 to -577 nt region, which is involved in mesocarp-specific expression. Gel mobility shift assay revealed a strong interaction of the leaf nuclear extract with the 21-bp region. An AGTTAGG core-sequence within this region was identified as a novel negative regulatory element controlling fruit-specificity of the MSP1 promoter. Abscisic acid (ABA) and copper (Cu(2+)) induced the activity of the promoter and its 5' deletions more effectively than methyl jasmonate (MeJa) and ethylene. In the mesocarp, the full length promoter showed stronger inducibility in response to ABA and Cu(2+) than its 5' deletions, while in leaves, the -420 nt fragment was the most inducible by ABA and Cu(2+). These results suggest that the MSP1 promoter and its regulatory regions are potentially useful for engineering fruit-specific and inducible gene expression in oil palm.
    Matched MeSH terms: Gene Expression Regulation, Plant/genetics; Gene Expression Regulation, Plant/physiology
  19. Fulltext SA-Mediated Regulation and Control of Abiotic Stress Tolerance in Rice
    Nadarajah K, Abdul Hamid NW, Abdul Rahman NSN
    Int J Mol Sci, 2021 May 25;22(11).
    PMID: 34070465 DOI: 10.3390/ijms22115591
    Environmental or abiotic stresses are a common threat that remains a constant and common challenge to all plants. These threats whether singular or in combination can have devastating effects on plants. As a semiaquatic plant, rice succumbs to the same threats. Here we systematically look into the involvement of salicylic acid (SA) in the regulation of abiotic stress in rice. Studies have shown that the level of endogenous salicylic acid (SA) is high in rice compared to any other plant species. The reason behind this elevated level and the contribution of this molecule towards abiotic stress management and other underlying mechanisms remains poorly understood in rice. In this review we will address various abiotic stresses that affect the biochemistry and physiology of rice and the role played by SA in its regulation. Further, this review will elucidate the potential mechanisms that control SA-mediated stress tolerance in rice, leading to future prospects and direction for investigation.
    Matched MeSH terms: Gene Expression Regulation, Plant/genetics; Gene Expression Regulation, Plant/physiology*
  20. Fulltext Identification of floral genes for sex determination in Calamus palustris Griff. by using suppression subtractive hybridization
    Ng CY, Wickneswari R, Choong CY
    Genet. Mol. Res., 2014;13(3):6037-49.
    PMID: 25117361 DOI: 10.4238/2014.August.7.18
    Calamus palustris Griff. is an economically important dioecious rattan species in Southeast Asia. However, dioecy and onset of flowering at 3-4 years old render uncertainties in desired female:male seedling ratios to establish a productive seed orchard for this rattan species. We constructed a subtractive library for male floral tissue to understand the genetic mechanism for gender determination in C. palustris. The subtractive library produced 1536 clones with 1419 clones of high quality. Reverse Northern screening showed 313 clones with differential expression, and sequence analyses clustered them into 205 unigenes, including 32 contigs and 173 singletons. The subtractive library was further validated with reverse transcription-quantitative polymerase chain reaction analysis. Homology identification classified the unigenes into 12 putative functional proteins with 83% unigenes showing significant match to proteins in databases. Functional annotations of these unigenes revealed genes involved in male flower development, including MADS-box genes, pollen-related genes, phytohormones for flower development, and male flower organ development. Our results showed that the male floral genes may play a vital role in sex determination in C. palustris. The identified genes can be exploited to understand the molecular basis of sex determination in C. palustris.
    Matched MeSH terms: Gene Expression Regulation, Plant
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links