Plant-based release system of negative air ions and its application on particulate matter removal.

Particulate matter (PM, especially PM2.5 with diameter 2.5 microns) has been regarded as the major air pollutant. Negative air ions (NAIs) could electrically charge PM and remove it much more efficiently. In this study, a bio-generator of NAIs has been developed, which helps plants to generate NAIs at around 100 × 106 ions/cm3 under pulsed electrical field (PEF) treatment. By using the bio-generator, PM2.5 concentration in a growth chamber could be reduced from around 500 to near 0 µg/m3 within 5 minutes. It could also be used to remove continuously generated PM. Upon PEF treatment, genes encoding oxidoreductases and other enzymes were up-regulated, some of which might contribute to the generation of superoxide anions (one of NAIs). On the other hand, the emission of large numbers of electrons from the surface/edge of plant leaves has been detected upon PEF treatment and these electrons might be captured by surrounding air molecules to generate high concentration of NAIs.

Valine-glutamine (VQ) motif coding genes are ancient and non-plant-specific with comprehensive expression regulation by various biotic and abiotic stresses.

BACKGROUND: Valine-glutamine (VQ) motif containing proteins play important roles in abiotic and biotic stress responses in plants. However, little is known about the origin and evolution as well as comprehensive expression regulation of the VQ gene family. RESULTS: In this study, we systematically surveyed this gene family in 50 plant genomes from algae, moss, gymnosperm and angiosperm and explored their presence in other species from animals, bacteria, fungi and viruses. No VQs were detected in all tested algae genomes and all genomes from moss, gymnosperm and angiosperm encode varying numbers of VQs. Interestingly, some of fungi, lower animals and bacteria also encode single to a few VQs. Thus, they are not plant-specific and should be regarded as an ancient family. Their family expansion was mainly due to segmental duplication followed by tandem duplication and mobile elements. Limited contribution of gene conversion was detected to the family evolution. Generally, VQs were very much conserved in their motif coding region and were under purifying selection. However, positive selection was also observed during species divergence. Many VQs were up- or down-regulated by various abiotic / biotic stresses and phytohormones in rice and Arabidopsis. They were also co-expressed with some of other stress-related genes. All of the expression data suggest a comprehensive expression regulation of the VQ gene family. CONCLUSIONS: We provide new insights into gene expansion, divergence, evolution and their expression regulation of this VQ family. VQs were detectable not only in plants but also in some of fungi, lower animals and bacteria, suggesting the evolutionary conservation and the ancient origin. Overall, VQs are non-plant-specific and play roles in abiotic / biotic responses or other biological processes through comprehensive expression regulation.

Negative Air Ions and Their Effects on Human Health and Air Quality Improvement.

Negative air ions (NAIs) have been discovered for more than 100 years and are widely used for air cleaning. Here, we have carried out a comprehensive reviewing on the effects of NAIs on humans/animals, and microorganisms, and plant development. The presence of NAIs is credited for increasing psychological health, productivity, and overall well-being but without consistent or reliable evidence in therapeutic effects and with controversy in anti-microorganisms. Reports also showed that NAIs could help people in relieving symptoms of allergies to dust, mold spores, and other allergens. Particulate matter (PM) is a major air pollutant that affects human health. Experimental data showed that NAIs could be used to high-efficiently remove PM. Finally, we have reviewed the plant-based NAI release system under the pulsed electric field (PEF) stimulation. This is a new NAI generation system which releases a huge amount of NAIs under the PEF treatment. The system may be used to freshen indoor air and reduce PM concentration in addition to enriching oxygen content and indoor decoration at home, school, hospital, airport, and other indoor areas.

Identification and molecular characterization of tissue-preferred rice genes and their upstream regularly sequences on a genome-wide level.

BACKGROUND: Gene upstream regularly sequences (URSs) can be used as one of the tools to annotate the biological functions of corresponding genes. In addition, tissue-preferred URSs are frequently used to drive the transgene expression exclusively in targeted tissues during plant transgenesis. Although many rice URSs have been molecularly characterized, it is still necessary and valuable to identify URSs that will benefit plant transformation and aid in analyzing gene function. RESULTS: In this study, we identified and characterized root-, seed-, leaf-, and panicle-preferred genes on a genome-wide level in rice. Subsequently, their expression patterns were confirmed through quantitative real-time RT-PCR (qRT-PCR) by randomly selecting 9candidate tissue-preferred genes. In addition, 5 tissue-preferred URSs were characterized by investigating the URS::GUS transgenic plants. Of these URS::GUS analyses, the transgenic plants harboring LOC_Os03g11350 URS::GUS construct showed the GUS activity only in young pollen. In contrast, when LOC_Os10g22450 URS was used to drive the reporter GUS gene, the GUS activity was detected only in mature pollen. Interestingly, the LOC_Os10g34360 URS was found to be vascular bundle preferred and its activities were restricted only to vascular bundles of leaves, roots and florets. In addition, we have also identified two URSs from genes LOC_Os02G15090 and LOC_Os06g31070 expressed in a seed-preferred manner showing the highest expression levels of GUS activities in mature seeds. CONCLUSION: By genome-wide analysis, we have identified tissue-preferred URSs, five of which were further characterized using transgenic plants harboring URS::GUS constructs. These data might provide some evidence for possible functions of the genes and be a valuable resource for tissue-preferred candidate URSs for plant transgenesis.

Genetic variation and expression diversity between grain and sweet sorghum lines.

BACKGROUND: Biological scientists have long sought after understanding how genes and their structural/functional changes contribute to morphological diversity. Though both grain (BT×623) and sweet (Keller) sorghum lines originated from the same species Sorghum bicolor L., they exhibit obvious phenotypic variations. However, the genome re-sequencing data revealed that they exhibited limited functional diversity in their encoding genes in a genome-wide level. The result raises the question how the obvious morphological variations between grain and sweet sorghum occurred in a relatively short evolutionary or domesticated period. RESULTS: We implemented an integrative approach by using computational and experimental analyses to provide a detail insight into phenotypic, genetic variation and expression diversity between BT×623 and Keller lines. We have investigated genome-wide expression divergence between BT×623 and Keller under normal and sucrose treatment. Through the data analysis, we detected more than 3,000 differentially expressed genes between these two varieties. Such expression divergence was partially contributed by differential cis-regulatory elements or DNA methylation, which was genetically determined by functionally divergent genes between these two varieties. Both tandem and segmental duplication played important roles in the genome evolution and expression divergence. CONCLUSION: Substantial differences in gene expression patterns between these two varieties have been observed. Such an expression divergence is genetically determined by the divergence in genome level.

Over-expression of OSRIP18 increases drought and salt tolerance in transgenic rice plants.

Both drought and high salinity stresses are major abiotic factors that limit the yield of agricultural crops. Transgenic techniques have been regarded as effective ways to improve crops in their tolerance to these abiotic stresses. Functional characterization of genes is the prerequisite to identify candidates for such improvement. Here, we have investigated the biological functions of an Oryza sativa Ribosome-inactivating protein gene 18 (OSRIP18) by ectopically expressing this gene under the control of CaMV 35S promoter in the rice genome. We have generated 11 independent transgenic rice plants and all of them showed significantly increased tolerance to drought and high salinity stresses. Global gene expression changes by Microarray analysis showed that more than 100 probe sets were detected with up-regulated expression abundance while signals from only three probe sets were down-regulated after over-expression of OSRIP18. Most of them were not regulated by drought or high salinity stresses. Our data suggested that the increased tolerance to these abiotic stresses in transgenic plants might be due to up-regulation of some stress-dependent/independent genes and OSRIP18 may be potentially useful in further improving plant tolerance to various abiotic stresses by over-expression.

Genome-wide expansion and expression divergence of the basic leucine zipper transcription factors in higher plants with an emphasis on sorghum.

Plant bZIP transcription factors play crucial roles in multiple biological processes. However, little is known about the sorghum bZIP gene family although the sorghum genome has been completely sequenced. In this study, we have carried out a genome-wide identification and characterization of this gene family in sorghum. Our data show that the genome encodes at least 92 bZIP transcription factors. These bZIP genes have been expanded mainly by segmental duplication. Such an expansion mechanism has also been observed in rice, arabidopsis and many other plant organisms, suggesting a common expansion mode of this gene family in plants. Further investigation shows that most of the bZIP members have been present in the most recent common ancestor of sorghum and rice and the major expansion would occur before the sorghum-rice split era. Although these bZIP genes have been duplicated with a long history, they exhibited limited functional divergence as shown by nonsynonymous substitutions (Ka)/synonymous substitutions (Ks) analyses. Their retention was mainly due to the high percentages of expression divergence. Our data also showed that this gene family might play a role in multiple developmental stages and tissues and might be regarded as important regulators of various abiotic stresses and sugar signaling.

The Efficacy of Plant-Based Ionizers in Removing Aerosol for COVID-19 Mitigation.

Small-sized droplets/aerosol transmission is one of the factors responsible for the spread of COVID-19, in addition to large droplets and surface contamination (fomites). While large droplets and surface contamination can be relatively easier to deal with (i.e., using mask and proper hygiene measures), aerosol presents a different challenge due to their ability to remain airborne for a long time. This calls for mitigation solutions that can rapidly eliminate the airborne aerosol. Pre-COVID-19, air ionizers have been touted as effective tools to eliminate small particulates. In this work, we sought to evaluate the efficacy of a novel plant-based ionizer in eliminating aerosol. It was found that factors such as the ion concentration, humidity, and ventilation can drastically affect the efficacy of aerosol removal. The aerosol removal rate was quantified in terms of ACH (air changes per hour) and CADR- (clean air delivery rate-) equivalent unit, with ACH as high as 12 and CADR as high as 141 ft3/minute being achieved by a plant-based ionizer in a small isolated room. This work provides an important and timely guidance on the effective deployment of ionizers in minimizing the risk of COVID-19 spread via airborne aerosol, especially in a poorly-ventilated environment.

Evolutionary history and stress regulation of the lectin superfamily in higher plants.

BACKGROUND: Lectins are a class of carbohydrate-binding proteins. They play roles in various biological processes. However, little is known about their evolutionary history and their functions in plant stress regulation. The availability of full genome sequences from various plant species makes it possible to perform a whole-genome exploration for further understanding their biological functions. RESULTS: Higher plant genomes encode large numbers of lectin proteins. Based on their domain structures and phylogenetic analyses, a new classification system has been proposed. In this system, 12 different families have been classified and four of them consist of recently identified plant lectin members. Further analyses show that some of lectin families exhibit species-specific expansion and rapid birth-and-death evolution. Tandem and segmental duplications have been regarded as the major mechanisms to drive lectin expansion although retrogenes also significantly contributed to the birth of new lectin genes in soybean and rice. Evidence shows that lectin genes have been involved in biotic/abiotic stress regulations and tandem/segmental duplications may be regarded as drivers for plants to adapt various environmental stresses through duplication followed by expression divergence. Each member of this gene superfamily may play specialized roles in a specific stress condition and function as a regulator of various environmental factors such as cold, drought and high salinity as well as biotic stresses. CONCLUSIONS: Our studies provide a new outline of the plant lectin gene superfamily and advance the understanding of plant lectin genes in lineage-specific expansion and their functions in biotic/abiotic stress-related developmental processes.

Assigning biological functions to rice genes by genome annotation, expression analysis and mutagenesis.

Rice is the first cereal genome to be completely sequenced. Since the completion of its genome sequencing, considerable progress has been made in multiple areas including the whole genome annotation, gene expression profiling, mutant collection, etc. Here, we summarize the current status of rice genome annotation and review the methodology of assigning biological functions to hundreds of thousands of rice genes as well as discuss the major limitations and the future perspective in rice functional genomics. Available data analysis shows that the rice genome encodes around 32,000 protein-coding genes. Expression analysis revealed at least 31,000 genes with expression evidence from full-length cDNA/EST collection or other transcript profiling. In addition, we have summarized various strategies to generate mutant population including natural, physical, chemical, T-DNA, transposon/retrotransposon or gene silencing based mutagenesis. Currently, more than 1 million of mutants have been generated and 27,551 of them have their flanking sequence tags. To assign biological functions to hundreds of thousands of rice genes, global co-operations are required, various genetic resources should be more easily accessible and diverse data from transcriptomics, proteomics, epigenetics, comparative genomics and bioinformatics should be integrated to better understand the functions of these genes and their regulatory mechanisms.

Comparative transcriptional profiling and evolutionary analysis of the GRAM domain family in eukaryotes.

The GRAM domain was found in glucosyltransferases, myotubularins and other membrane-associated proteins. So far, functions for majority of these proteins are yet to be uncovered. In order to address the evolutionary and functional significance of this family members, we have performed a comprehensive investigation on their genome-wide identification, phylogenetic relationship and expression divergence in five different organisms representing monocot/dicot plants, vertebrate/invertebrate animals and yeast, namely, Oryza sativa, Arabidopsis thaliana, Mus musculus, Drosophila melanogaster and Saccharomyces cerevisiae, respectively. We have identified 65 members of GRAM domain family from these organisms. Our data revealed that this family was an ancient group and various organisms had evolved into different family sizes. Large-scale genome duplication and divergence in both expression patterns and functions were significantly contributed to the expansion and retention of this family. Mouse and Drosophila members showed higher divergences in their proteins as indicated by higher Ka/Ks ratios and possessed multiple domains in various combinations. However, in plants, their protein functions were possibly retained with a relatively low divergence as signified by lower Ka/Ks ratios and only one additional domain was combined during evolution. On the other hand, this family in all five organisms exhibited high divergence in their expression patterns both at tissue level and under various biotic and abiotic stresses. These highly divergent expression patterns unraveled the complexity of functions of GRAM domain family. Each member may play specialized roles in a specific tissue or stress condition and may function as regulators of environmental and hormonal signaling.

A Comprehensive Survey on the Terpene Synthase Gene Family Provides New Insight into Its Evolutionary Patterns.

Terpenes are organic compounds and play important roles in plant growth and development as well as in mediating interactions of plants with the environment. Terpene synthases (TPSs) are the key enzymes responsible for the biosynthesis of terpenes. Although some species were employed for the genome-wide identification and characterization of the TPS family, limited information is available regarding the evolution, expansion, and retention mechanisms occurring in this gene family. We performed a genome-wide identification of the TPS family members in 50 sequenced genomes. Additionally, we also characterized the TPS family from aromatic spearmint and basil plants using RNA-Seq data. No TPSs were identified in algae genomes but the remaining plant species encoded various numbers of the family members ranging from 2 to 79 full-length TPSs. Some species showed lineage-specific expansion of certain subfamilies, which might have contributed toward species or ecotype divergence or environmental adaptation. A large-scale family expansion was observed mainly in dicot and monocot plants, which was accompanied by frequent domain loss. Both tandem and segmental duplication significantly contributed toward family expansion and expression divergence and played important roles in the survival of these expanded genes. Our data provide new insight into the TPS family expansion and evolution and suggest that TPSs might have originated from isoprenyl diphosphate synthase genes.

A comprehensive transcriptional profiling of the WRKY gene family in rice under various abiotic and phytohormone treatments.

WRKY transcription factors play important roles in the regulation of various biological processes. We have analyzed the publicly available rice genome sequence databases and predicted 103 genes encoding WRKY transcription factors. Among them, the majority of rice WRKY genes (77.7%) were located in duplicated regions; 45.6% of WRKY genes were fragmentally duplicated and 35% of them were tandemly duplicated. These results suggested that genome duplications might be regarded as a major mechanism for expansion of this family in the rice genome. Subsequently, we analyzed their expression profiles under normal and abiotic stress, as well as various hormone treatments. Under normal growth conditions, 65 WRKY genes were expressed differentially either in their transcript abundance or in their expression patterns. Under abiotic (cold, drought and salinity) stresses and various phytohormone treatments, 54 WRKY genes exhibited significant differences in their transcript abundance; among them three genes were expressed only in stressed conditions. Among the stress-inducible genes, 13 genes were regulated only by abiotic stresses, another set of 13 genes were responsive to only phytohormone treatments and the remaining 28 genes were regulated by both factors, suggesting an interaction between abiotic stress and hormone signaling. On the other hand, we have also surveyed the expression divergence of duplicated genes under normal or stressed conditions, and the results showed that high expression divergence has occurred not only among fragmentally but also among tandemly duplicated genes. These results suggested that the high expression divergence could be one of the mechanisms for the retention of these duplicated WRKY genes.

Comparative and evolutionary analysis of genes encoding small GTPases and their activating proteins in eukaryotic genomes.

Both small GTPase and its activating protein (GAP) superfamilies exist in various eukaryotes. The small GTPases regulate a wide variety of cellular processes by cycling between active GTP- and inactive GAP-bound conformations. The GAPs promote GTPase inactivation by stimulating the GTP hydrolysis. In this study, we identified 111 small GTPases and 85 GAPs in rice, 65 GAPs in Arabidopsis, 90 small GTPases in Drosophila melanogaster, and 35 GAPs in Saccharomyces cerevisiaeby genome-wide analysis. We then analyzed and compared a total of 498 small GTPases and 422 GAPs from these four eukaryotic and human genomes. Both animals and yeast genomes contained five families of small GTPases and their GAPs. However, plants had only four of these five families because of a lack of the Ras and RasGAP genes. Small GTPases were conserved with common motifs, but GAPs exhibited higher and much more rapid divergence. On the basis of phylogenetic analysis of all small GTPases and GAPs in five eukaryotic organisms, we estimated that their ancestors had small sizes of small GTPases and GAPs and their large-scale expansions occurred after the divergence from their ancestors. Further investigation showed that genome duplications represented the major mechanism for such expansions. Nonsynonymous substitutions per site (Ka) and synonymous substitutions per site (Ks) analyses showed that most of the divergence due to a positive selection occurred in common ancestors, suggesting a major functional divergence in an ancient era.

Expansion Mechanisms and Evolutionary History on Genes Encoding DNA Glycosylases and Their Involvement in Stress and Hormone Signaling.

DNA glycosylases catalyze the release of methylated bases. They play vital roles in the base excision repair pathway and might also function in DNA demethylation. At least three families of DNA glycosylases have been identified, which included 3'-methyladenine DNA glycosylase (MDG) I, MDG II, and HhH-GPD (Helix-hairpin-Helix and Glycine/Proline/aspartate (D)). However, little is known on their genome-wide identification, expansion, and evolutionary history as well as their expression profiling and biological functions. In this study, we have genome-widely identified and evolutionarily characterized these family members. Generally, a genome encodes only one MDG II gene in most of organisms. No MDG I or MDG II gene was detected in green algae. However, HhH-GPD genes were detectable in all available organisms. The ancestor species contain small size of MDG I and HhH-GPD families. These two families were mainly expanded through the whole-genome duplication and segmental duplication. They were evolutionarily conserved and were generally under purifying selection. However, we have detected recent positive selection among the Oryza genus, which might play roles in species divergence. Further investigation showed that expression divergence played important roles in gene survival after expansion. All of these family genes were expressed in most of developmental stages and tissues in rice plants. High ratios of family genes were downregulated by drought and fungus pathogen as well as abscisic acid (ABA) and jasmonic acid (JA) treatments, suggesting a negative regulation in response to drought stress and pathogen infection through ABA- and/or JA-dependent hormone signaling pathway.

Improving protein content and quality by over-expressing artificially synthetic fusion proteins with high lysine and threonine constituent in rice plants.

Rice grains are rich in starch but low in protein with very low level of both lysine and threonine. Thus, it is important to further improve protein quality and quantity, especially to increase lysine and threonine content in rice grains. We artificially synthesized two new genes by fusing endogenous rice genes with lysine (K)/threonine (T) motif (TKTKK) coding sequences. They were designated as TKTKK1 and TKTKK2 and their encoded proteins consist of 73.1% and 83.5% of lysine/threonine, respectively. These two genes were under the control of 35S promoter and were independently introduced into the rice genome to generate transgenic plants. Our data showed that overexpression of TKTKK1 generated stable proteins with expected molecular weight and the transgenic rice seeds significantly increased lysine, threonine, total amino acids and crude protein content by 33.87%, 21.21%, 19.43% and 20.45%, respectively when compared with wild type control; significant improvement was also observed in transgenic rice seeds overexpressing TKTKK2. However, limited improvement in protein quality and quantity was observed in transgenic seeds carrying tandom array of these two new genes. Our data provide the basis and alternative strategy on further improving protein quality and quantity in other crops or vegetable plants by synthetic biology.

Sucrose metabolism gene families and their biological functions.

Sucrose, as the main product of photosynthesis, plays crucial roles in plant development. Although studies on general metabolism pathway were well documented, less information is available on the genome-wide identification of these genes, their expansion and evolutionary history as well as their biological functions. We focused on four sucrose metabolism related gene families including sucrose synthase, sucrose phosphate synthase, sucrose phosphate phosphatase and UDP-glucose pyrophosphorylase. These gene families exhibited different expansion and evolutionary history as their host genomes experienced differentiated rates of the whole genome duplication, tandem and segmental duplication, or mobile element mediated gene gain and loss. They were evolutionarily conserved under purifying selection among species and expression divergence played important roles for gene survival after expansion. However, we have detected recent positive selection during intra-species divergence. Overexpression of 15 sorghum genes in Arabidopsis revealed their roles in biomass accumulation, flowering time control, seed germination and response to high salinity and sugar stresses. Our studies uncovered the molecular mechanisms of gene expansion and evolution and also provided new insight into the role of positive selection in intra-species divergence. Overexpression data revealed novel biological functions of these genes in flowering time control and seed germination under normal and stress conditions.

A novel binary T-vector with the GFP reporter gene for promoter characterization.

Several strategies have been developed to clone PCR fragments into desired vectors. However, most of commercially available T-vectors are not binary vectors and cannot be directly used for Agrobacterium-mediated plant genetic transformation. In this study, a novel binary T-vector was constructed by integrating two AhdI restriction sites into the backbone vector pCAMBIA 1300. The T-vector also contains a GFP reporter gene and thus, can be used to analyze promoter activity by monitoring the reporter gene. On the other hand, identification and characterization of various promoters not only benefit the functional annotation of their genes but also provide alternative candidates to be used to drive interesting genes for plant genetic improvement by transgenesis. More than 1,000 putative pollen-specific rice genes have been identified in a genome-wide level. Among them, 67 highly expressed genes were further characterized. One of the pollen-specific genes LOC_Os10g35930 was further surveyed in its expression patterns with more details by quantitative real-time reverse-transcription PCR (qRT-PCR) analysis. Finally, its promoter activity was further investigated by analyzing transgenic rice plants carrying the promoter::GFP cassette, which was constructed from the newly developed T-vector. The reporter GFP gene expression in these transgenic plants showed that the promoter was active only in mature but not in germinated pollens.

Engineering geminivirus resistance in Jatropha curcus.

BACKGROUND: Jatropha curcus is a good candidate plant for biodiesel production in tropical and subtropical regions. However, J. curcus is susceptible to the geminivirus Indian cassava mosaic virus (ICMV), and frequent viral disease outbreaks severely limit productivity. Therefore the development of J. curcus to carry on durable virus resistance remains crucial and poses a major biotechnological challenge. RESULTS: We generated transgenic J. curcus plants expressing a hairpin, double-stranded (ds) RNA with sequences homologous to five key genes of ICMV-Dha strain DNA-A, which silences sequence-related viral genes thereby conferring ICMV resistance. Two rounds of virus inoculation were conducted via vacuum infiltration of ICMV-Dha. The durability and heritability of resistance conferred by the dsRNA was further tested to ascertain that T1 progeny transgenic plants were resistant to the ICMV-SG strain, which shared 94.5% nucleotides identity with the ICMV-Dha strain. Quantitative PCR analysis showed that resistant transgenic lines had no detectable virus. CONCLUSIONS: In this study we developed transgenic J. curcus plants to include a resistance to prevailing geminiviruses in Asia. These virus-resistant transgenic J. curcus plants can be used in various Jatropha breeding programs.

Functional genomics of bio-energy plants and related patent activities.

With dwindling fossil oil resources and increased economic growth of many developing countries due to globalization, energy driven from an alternative source such as bio-energy in a sustainable fashion is the need of the hour. However, production of energy from biological source is relatively expensive due to low starch and sugar contents of bioenergy plants leading to lower oil yield and reduced quality along with lower conversion efficiency of feedstock. In this context genetic improvement of bio-energy plants offers a viable solution. In this manuscript, we reviewed the current status of functional genomics studies and related patent activities in bio-energy plants. Currently, genomes of considerable bio-energy plants have been sequenced or are in progress and also large amount of expression sequence tags (EST) or cDNA sequences are available from them. These studies provide fundamental data for more reliable genome annotation and as a result, several genomes have been annotated in a genome-wide level. In addition to this effort, various mutagenesis tools have also been employed to develop mutant populations for characterization of genes that are involved in bioenergy quantitative traits. With the progress made on functional genomics of important bio-energy plants, more patents were filed with a significant number of them focusing on genes and DNA sequences which may involve in improvement of bio-energy traits including higher yield and quality of starch, sugar and oil. We also believe that these studies will lead to the generation of genetically altered plants with improved tolerance to various abiotic and biotic stresses.