Green Organisms Research Articles

GreenPhos, a universal method for in-depth measurement of plant phosphoproteomes with high quantitative reproducibility

Protein phosphorylation regulates a variety of important cellular and physiological processes in plants. In-depth profiling of plant phosphoproteomes has been more technically challenging than that of animal phosphoproteomes. This is largely due to the need to improve protein extraction efficiency from plant cells, which have a dense cell wall, and to minimize sample loss resulting from the stringent sample clean-up steps required for the removal of a large amount of biomolecules interfering with phosphopeptide purification and mass spectrometry analysis. To this end, we developed a method with a streamlined workflow for highly efficient purification of phosphopeptides from tissues of various green organisms including Arabidopsis, rice, tomato, and Chlamydomonas reinhardtii, enabling in-depth identification with high quantitative reproducibility of about 11 000 phosphosites, the greatest depth achieved so far with single liquid chromatography-mass spectrometry (LC–MS) runs operated in a data-dependent acquisition (DDA) mode. The mainstay features of the method are the minimal sample loss achieved through elimination of sample clean-up before protease digestion and of desalting before phosphopeptide enrichment and hence the dramatic increases of time- and cost-effectiveness. The method, named GreenPhos, combined with single-shot LC–MS, enabled in-depth quantitative identification of Arabidopsis phosphoproteins, including differentially phosphorylated spliceosomal proteins, at multiple time points during salt stress and a number of kinase substrate motifs. GreenPhos is expected to serve as a universal method for purification of plant phosphopeptides, which, if samples are further fractionated and analyzed by multiple LC–MS runs, could enable measurement of plant phosphoproteomes with an unprecedented depth using a given mass spectrometry technology.

Flavodiiron-mediated O2 photoreduction at photosystem I acceptor-side provides photoprotection to conifer thylakoids in early spring

Green organisms evolve oxygen (O2) via photosynthesis and consume it by respiration. Generally, net O2 consumption only becomes dominant when photosynthesis is suppressed at night. Here, we show that green thylakoid membranes of Scots pine (Pinus sylvestris L) and Norway spruce (Picea abies) needles display strong O2 consumption even in the presence of light when extremely low temperatures coincide with high solar irradiation during early spring (ES). By employing different electron transport chain inhibitors, we show that this unusual light-induced O2 consumption occurs around photosystem (PS) I and correlates with higher abundance of flavodiiron (Flv) A protein in ES thylakoids. With P700 absorption changes, we demonstrate that electron scavenging from the acceptor-side of PSI via O2 photoreduction is a major alternative pathway in ES. This photoprotection mechanism in vascular plants indicates that conifers have developed an adaptative evolution trajectory for growing in harsh environments.

Caloric Value of Biomass based Power Plants, Life Cycle Assessment and Techno Economic of Different Crops for M.P. (India)

<p>Solar radiation incident on green plant and other photo synthesis organism performs two basic functions such as temperature control for chemical reaction to proceed and the process of photosynthesis. The fundamental conversion process in green plant is photosynthesis which is process of combining CO<sub>2</sub> from the atmosphere with water and light energy to produce oxygen and carbohydrates<sup>1</sup>.</p><p> X [CO<sub>2</sub>] + Y [H<sub>2</sub>O] + light energy photosynthesis X[O<sub>2</sub>] + Y [Cx H<sub>2</sub>O]</p><p> Y [Cx H<sub>2</sub>O] is used to indicate the carbohydrates.</p><p>The world population has increased at an explosive rate from 1.65 billion to just over 6 billion in the 20<sup>th</sup> century, and continues to increase. In the same century, mankind has consumed over 875 billion barrels of oil and it is very likely that even more oil will be consumed in the present century. Annual energy use in developing countries has risen from 55 to 212 kg oil equivalent over the last thirty years, while developed countries use as much as 650 kg oil equivalent per person. In his synopsis ‘Trilemma’ Three major problems threatening world survival’, foresees a three-fold challenge in the 21st century: how can we achieve economic growth, supply food and energy resources, while conserving the environment? To overcome the Trilemma, developing and introducing more efficient energy conversion technologies is therefore important, for fossil fuels as well as renewable fuels. This thesis addresses the question how biomass may be used more efficiently and economically than it is being used today. Wider use of biomass, a clean, renewable and CO<sub>2</sub> neutral feedstock may extend the lifetime of our fossil fuels resources and alleviate global warming problems. Another advantage of using of biomass as a source of energy is to make developed countries less interdependent on oil- exporting countries, and thereby reduce political tension. Furthermore, the economies of agricultural regions growing energy crops benefit as new jobs are created<sup>1</sup>. Biomass primary energy sources: Past, present and future in particular wood, has historically been an important energy source for fires, ovens and stoves. During the Industrial Revolution, coal displaced biomass because of its high energy content and because it is available in large quantities at low cost. At the beginning of the 20th century, oil supplied only 4 % of the world’s energy. Decades later it became the most important energy source. Especially developed countries are highly dependent on oil, which supplies about 96 % of their transportation energy. With world energy demand projected to rise by about 40 % from now to 2020, photosynthesis. Rajiv Gandhi Proudyogiki Vishwvidhalaya implemented the National Policy for Management of Crop Residues to protect the parali (crop residue). On December 10, 2015, the National Green Tribunal (NGT) had banned crop residue burning in the states of Rajasthan, Uttar Pradesh, Haryana and Punjab. Burning crop residue is a crime under Section 188 of the IPC and under the Air and Pollution Control Act of 1981. The Delhi high court had also ordered against burning residues, while Punjab government imposed a penalty of Rs 73.2 lakh farmers in 2016 for burning of crop residue<sup>3</sup>.</p>

Precise estimation of chlorophyll a, b and carotenoid content by deconvolution of the absorption spectrum and new simultaneous equations for Chl determination.

The precise determination of photosynthetic pigment content in green organisms, chlorophylls (Chls) and carotenoids (Cars), is important to investigate many photosynthetic processes such as responses to environmental fluctuations or to gene mutations, as well as to interpret biochemical and structural results obtained on purified membranes and photosynthetic complexes. The most utilized methods for determination by spectrophotometry of Chl content in solution, usually 80% acetone, are based on the use of simultaneous equations. The advantages are the easiness and speed over chromatography, which also requires less common equipment. The disadvantage is that issues in sample preparation or in the measurement are not detectable, which could lead to wrong results. Here we propose a fast, accurate and (almost) error-proof method to measure Chl a, Chl b and also total Car content in a solution of pigments extracted from tissue, membranes or purified complexes. The method is based on the fit of the absorption spectrum of the acetone extract using the spectra of purified pigments as references. We show how this method allows a more precise and accurate estimation of pigment content as compared to classical equations, even in incorrectly prepared acetone solutions. Moreover, the method allows the discovery of artifacts in sample preparation or measurement and thus drastically reduces the risk of mistakes. Examples obtained on purified complexes are also discussed. Based on newly acquired Chl spectra, we also propose a new set of improved simultaneous equations that provide slightly different but more reliable results in comparison with the currently used equations.

EARLY STARVATION 1 Is a Functionally Conserved Protein Promoting Gravitropic Responses in Plants by Forming Starch Granules.

Starch granules in the endodermis of plant hypocotyls act as statoliths that promote hypocotyl negative gravitropism—the directional growth of hypocotyls against gravity—in the dark. To identify the molecular components that regulate hypocotyl negative gravitropism, we performed a mutagenesis screen and isolated reduced gravitropic 1 (rgv1) mutants that lack starch granules in their hypocotyl endodermis and show reduced hypocotyl negative gravitropism in the dark. Using whole genome sequencing, we identified three different rgv1 mutants that are allelic to the previously reported early starvation 1 mutant, which is rapidly depleted of starch just before the dawn. ESV1 orthologs are present in starch-producing green organisms, suggesting ESV1 is a functionally conserved protein necessary for the formation of starch granules. Consistent with this, we found that liverwort and rice ESV1 can complement the Arabidopsis ESV1 mutant phenotype for both starch granules and hypocotyl negative gravitropism. To further investigate the function of ESV1 in other plants, we isolated rice ESV1 mutants and found that they show reduced levels of starch in their leaves and loosely packed starch granules in their grains. Both Arabidopsis and rice ESV1 mutants also lack starch granules in root columella and show reduced root gravitropism. Together, these results indicate ESV1 is a functionally conserved protein that promotes gravitropic responses in plants via its role in starch granule formation.

Isolation and characterization of a large photosystem I-light-harvesting complex II supercomplex with an additional Lhca1-a4 dimer in Arabidopsis.

The biological conversion of light energy into chemical energy is performed by a flexible photosynthetic machinery located in the thylakoid membranes. Photosystems I and II (PSI and PSII) are the two complexes able to harvest light. PSI is the last complex of the electron transport chain and is composed of multiple subunits: the proteins building the catalytic core complex that are well conserved between oxygenic photosynthetic organisms, and, in green organisms, the membrane light-harvesting complexes (Lhc) necessary to increase light absorption. In plants, four Lhca proteins (Lhca1-4) make up the antenna system of PSI, which can be further extended to optimize photosynthesis by reversible binding of LHCII, the main antenna complex of photosystem II. Here, we used biochemistry and electron microscopy in Arabidopsis to reveal a previously unknown supercomplex of PSI with LHCII that contains an additional Lhca1-a4 dimer bound on the PsaB-PsaI-PsaH side of the complex. This finding contradicts recent structural studies suggesting that the presence of an Lhca dimer at this position is an exclusive feature of algal PSI. We discuss the features of the additional Lhca dimer in the large plant PSI-LHCII supercomplex and the differences with the algal PSI. Our work provides further insights into the intricate structural plasticity of photosystems.

The Plant Translatome Surveyed by Ribosome Profiling.

Although transcriptome changes have long been recognized as a mechanism to induce tentative substitution of expressed genes in diverse biological processes in plants, the regulation of translation-the final step of the central dogma of molecular biology-emerged as an alternative and prominent layer in defining the output of genes. Despite these demands, the genome-wide analysis of protein synthesis has posed technical challenges, resulting in the plant translatome being poorly understood. The development of ribosome profiling promises to address the hidden aspects of translation, and its application to plants is revolutionizing our knowledge of the translatome. This review outlines the array of recent findings provided by ribosome profiling and illustrates the power of the versatile technique in green organisms.

Morphology supports ­the setaphyte hypothesis: mosses plus liverworts form a natural group

The origin and early diversification of land plants is one of the major unresolved problems in evolutionary biology. Occurring nearly half a billion years ago, the transmigration of green organisms to land changed the landscape and provided the food source for terrestrial life to invade a vast uninhabited space, adapt and radiate. Although bryophytes (mosses, liverworts and hornworts) are often regarded as the earliest terrestrial organisms, the order of their divergence remains contentious even as molecular analyses become more conclusive with expanded taxon sampling, massive genetic data and more sophisticated methods of analysis (Cox et al. 2018; Morris et al. 2018). Indeed, virtually every combination of relationships among bryophytes has been proposed based on molecules (Qiu et al. 2006; Wickett et al. 2014; Cox et al. 2018). Fortunately, in 2018 it appears that we are approaching a consensus based on molecules, and that is that although bryophytes may or may not be monophyletic, mosses plus liverworts form a natural group (Puttick et al. 2018). In this essay, we point out that this inference is neither new nor surprising as it has been the fundamental conclusion of morphological analyses for over 25 years starting with an exhaustive cladistic analysis of characters associated with motile cell development in green plants (Garbary et al. 1993).

Functions and Evolution of Lhcb Isoforms Composing LHCII, the Major Light Harvesting Complex of Photosystem II of Green Eukaryotic Organisms.

Oxygenic photosynthesis provides energy and oxygen for almost all forms of life on earth. This process is based on the energy of photons, which is used to split water and use its electrons to reduce carbon atoms to create organic molecules and thus fix the light energy into a chemical form. Two photosytems working in series are involved in light harvesting and conversion. Both are multi-protein supercomplexes composed of a core complex, where the photochemical reaction takes place, and an antenna system involved in light harvesting. In plants and green algae, the antenna of photosystem II, the photosynthetic complex involved in water splitting, comprises the Light Harvesting Complex II (LHCII) trimers, the most abundant membrane protein on earth. LHCII is composed of highly conserved Lhcb isoforms and all green organisms count a high number of Lhcb. In vascular plants they are classified in three distinct subclasses, Lhcb1, 2 and 3, while in algae and non-vascular plants, these isoforms are less differentiated and called Lhcbm proteins. In this review, we compare LHCII proteins of different organisms, from green algae to angiosperms, and discuss the role of the modifications that occurred through evolution. We highlight the various functions of the different isoforms in photosynthesis, ranging from light harvesting, a common role to all these proteins, to regulations of photosynthesis that rely on specific isoforms.

Julius Sachs (1868): The father of plant physiology.

The year 2018 marks the 150th anniversary of the first publication of Julius von Sachs' (1832-1897) Lehrbuch der Botanik (Textbook of Botany), which provided a comprehensive summary of what was then known about the plant sciences. Three years earlier, in 1865, Sachs produced the equally impressive Handbuch der Experimental-Physiologie der Pflanzen (Handbook of Experimental Plant Physiology), which summarized the state of knowledge in all aspects of the discipline known today as plant physiology. Both of these books provided numerous insights based on Sachs' seminal experiments. By virtue of a reliance on detailed empirical observation and the rigorous application of chemical and physical principles, it is fair to say that the publication of these two monumental works marked the beginning of what can be called "modern-day" plant science. Moreover, Sachs' Lehrbuch der Botanik prefigured the ascendance of plant molecular biology and the systems biology of photoautotrophic organisms. Regrettably, many of the insights of this great scientist have been forgotten by the generations who followed. It is only fitting, therefore, that the anniversary of the publication of the Lehrbuch der Botanik and the career of "the father of plant physiology" should be honored and reviewed, particularly because Sachs established the physiology of green organisms as an integral branch of botany and incorporated a Darwinian perspective into plant biology. Here we highlight key insights, with particular emphasis on Sachs' detailed discussion of sexual reproduction at the cellular level and his endorsement of Darwinian evolution.

Translation and Co-translational Membrane Engagement of Plastid-encoded Chlorophyll-binding Proteins Are Not Influenced by Chlorophyll Availability in Maize.

Chlorophyll is an indispensable constituent of the photosynthetic machinery in green organisms. Bound by apoproteins of photosystems I and II, chlorophyll performs light-harvesting and charge separation. Due to the phototoxic nature of free chlorophyll and its precursors, chlorophyll synthesis is regulated to comply with the availability of nascent chlorophyll-binding apoproteins. Conversely, the synthesis and co-translational insertion of such proteins into the thylakoid membrane have been suggested to be influenced by chlorophyll availability. In this study, we addressed these hypotheses by using ribosome profiling to examine the synthesis and membrane targeting of chlorophyll-binding apoproteins in chlorophyll-deficient chlH maize mutants (Zm-chlH). ChlH encodes the H subunit of the magnesium chelatase (also known as GUN5), which catalyzes the first committed step in chlorophyll synthesis. Our results show that the number and distribution of ribosomes on plastid mRNAs encoding chlorophyll-binding apoproteins are not substantially altered in Zm-chlH mutants, suggesting that chlorophyll has no impact on ribosome dynamics. Additionally, a Zm-chlH mutation does not change the amino acid position at which nascent chlorophyll-binding apoproteins engage the thylakoid membrane, nor the efficiency with which membrane-engagement occurs. Together, these results provide evidence that chlorophyll availability does not selectively activate the translation of plastid mRNAs encoding chlorophyll apoproteins. Our results imply that co- or post-translational proteolysis of apoproteins is the primary mechanism that adjusts apoprotein abundance to chlorophyll availability in plants.

Sequence and coexpression analysis of iron-regulated ZIP transporter genes reveals crossing points between iron acquisition strategies in green algae and land plants

Dicotyledonous plants, such as Arabidopsis, acquire soil iron using a reduction-based mechanism, named Strategy I, where the final step involves Fe2+ import by the ZIP-family transporter AtIRT1. The universal presence of IRT1-like genes, suggests that Strategy I represents a basic process in the green lineage. However, for some green organisms, like Chlamydomonas and rice, alternative iron-acquisition mechanisms are known. We aimed to outline potential interactions between Strategy I and alternative iron acquisition mechanisms. We investigated gene-coexpression networks in Chlamydomonas, rice and Arabidopsis, and used the sequences of the variable regions of the selected IRT proteins to identify the conservation of key amino acids. IRT genes in Chlamydomonas and rice were found to be closely coexpressed with components of alternative available iron-acquisition systems. On protein level, we could observe conservation of potential phosphorylation sites in close proximity to predicted or experimentally-demonstrated ubiquitination sites. Data suggest that the regulation of Strategy I is closely connected to alternative existing iron-acquisition strategies. Transciptional control, together with potential post-transcriptional modifications of IRT transporters, may be involved in fine-tuning iron import. This study provides a basis for experimentally analyzing the regulation of iron acquisition in an evolutionary context.

Rapid method for DNA isolation from a tough cell wall green alga Tetraspora sp. CU2551.

Genetic studies are important to understand the complex biological system of various organisms. Some eukaryotic green organisms have tough cell wall which precludes the efficient extraction of the genetic materials. Here, we developed the method for simple and rapid isolation of high quality DNA from a green alga Tetraspora sp. CU2551. The cell homogenization procedures were combined with physical force plus heat treatment to disrupt the cell envelope of Tetraspora sp. CU2551. Without protease treatment, vortexing with glass bead for 30-105s at 70°C led to the isolation of a high purity DNA which was suitable for downstream process. The improved method was successfully developed and could be applied for the rapid isolation of DNA from other unicellular and filamentous green microalgal strains.

Structural diversity of signal recognition particle RNAs in plastids

One of the pathways for protein targeting to the plasma membrane in bacteria utilizes the co-translationally acting signal recognition particle (SRP), a universally conserved ribonucleoprotein complex consisting of a 54 kDa protein and a functional RNA. An interesting exception is the higher plant chloroplast SRP, which lacks the otherwise essential RNA component. Furthermore, green plant chloroplasts have an additional post-translational SRP-dependent transport system in which the chloroplast-specific cpSRP43 protein binds to imported substrate proteins and to the conserved 54 kDa SRP subunit (cpSRP54). While homologs to the bacterial SRP protein and RNA component previously have been identified in genome sequences of red algae and diatoms, a recent study investigated the evolution of the green plant SRP system.1 Analysis of hundreds of plastid and nuclear genomes showed a surprising pattern of multiple losses of the plastid SRP RNA during evolution and a widespread presence in all non-spermatophyte plants and green algae. Contrary to expectations, all green organisms that have an identified cpSRP RNA also contain a cpSRP43. Notably, the structure of the plastid SRP RNAs is much more diverse than that of bacterial SRP RNAs. The apical GNRA tetraloop is only conserved in organisms of the red lineage and basal organisms of the green lineage, whereas further chloroplast SRP RNAs are characterized by atypical, mostly enlarged apical loops.

Low oxygen response mechanisms in green organisms.

Low oxygen stress often occurs during the life of green organisms, mostly due to the environmental conditions affecting oxygen availability. Both plants and algae respond to low oxygen by resetting their metabolism. The shift from mitochondrial respiration to fermentation is the hallmark of anaerobic metabolism in most organisms. This involves a modified carbohydrate metabolism coupled with glycolysis and fermentation. For a coordinated response to low oxygen, plants exploit various molecular mechanisms to sense when oxygen is either absent or in limited amounts. In Arabidopsis thaliana, a direct oxygen sensing system has recently been discovered, where a conserved N-terminal motif on some ethylene responsive factors (ERFs), targets the fate of the protein under normoxia/hypoxia. In Oryza sativa, this same group of ERFs drives physiological and anatomical modifications that vary in relation to the genotype studied. The microalga Chlamydomonas reinhardtii responses to low oxygen seem to have evolved independently of higher plants, posing questions on how the fermentative metabolism is modulated. In this review, we summarize the most recent findings related to these topics, highlighting promising developments for the future.

Engineered tobacco and microalgae secreting the fungal laccase POXA1b reduce phenol content in olive oil mill wastewater

Olive oil mill wastewaters (OMWs) are characterised by low pH and a high content of mono- and polyaromatic compounds that exert microbial and phytotoxic activity. The laccase cDNA of the poxA1b gene from Pleurotus ostreatus, carrying a signal peptide sequence for enzyme secretion and driven by the CaMV 35S promoter, was cloned into a plant expression vector. Nuclear genetic transformation was carried out by co-cultivation of Agrobacterium tumefaciens with tobacco cv Samsun NN leaves and cells of five different microalgae accessions belonging to the genera Chlamydomonas, Chlorella and Ankistrodesmus. Transgenic plants and microalgae were able to express and secrete the recombinant laccase in the root exudates and the culture medium, respectively. In comparison to untransformed controls, the ability to reduce phenol content in OMW solution was enhanced up to 2.8-fold in transgenic tobacco lines and by up to about 40% in two microalgae accessions. The present work provides new evidence for metabolic improvement of green organisms through the transgenic approach to remediation.

Meiosis in flowering plants and other green organisms

Sexual eukaryotes generate gametes using a specialized cell division called meiosis that serves both to halve the number of chromosomes and to reshuffle genetic variation present in the parent. The nature and mechanism of the meiotic cell division in plants and its effect on genetic variation are reviewed here. As flowers are the site of meiosis and fertilization in angiosperms, meiotic control will be considered within this developmental context. Finally, we review what is known about the control of meiosis in green algae and non-flowering land plants and discuss evolutionary transitions relating to meiosis that have occurred in the lineages giving rise to the angiosperms.

Distribution of Two Distinct Genotypes of Citrus Greening Organism in the Ryukyu Islands of Japan

Asian type Candidatus Liberibacter asiaticus (Las, citrus greening organism) is severely dam- aging citrus production in Asia including Japan. Our previous study suggested that the bacteriophage- type DNA polymerase region (DNA pol) would be useful for molecular differentiation in different Southeast Asian Las isolates. Moreover, Las isolates originated from most of the Southeast Asian regions harbor the DNA pol gene, whereas Japanese ones lack this region. These preliminary findings lead us to a hypothesis that all Japanese isolates lack DNA pol. To try this hypothesis, we collected citrus leaf samples infected with Las throughout the Ryukyu Islands, and examined them by a duplex PCR that could simultaneously amplify two DNA fragments of DNA pol and nusG-rplK operon of Las. The duplex PCR was applied to the collection of 65 Las isolates. Both DNA pol and nusG-rplK operon were successfully amplified from nine isolates, whereas only nusG-rplK operon was amplified with the other 56 isolates. These nine isolates with DNA pol originated from the Hateruma, Irabu, Kohama, Miyako, Tarama, and Yonaguni Islands, which are geographically close to Taiwan. The nucleotide sequence of DNA pol of these nine isolates was identical, and was also the same as four Taiwanese isolates reported previously. These results suggest that Japanese Las isolates comprise at least two distinct genotypes, and the genotype that had DNA pol is highly homogeneous.

Grand Opportunities in Plant Science to Address the Grand Challenges Facing the Planet

For people, plants can seem like aliens. Movements are typically slow, and many consider plants “slow and low life [sLow life]” (Hangarter, 2009). Their appearance and behavior are so different from ourselves that we are in awe when we learn that many of the central functions of plants and humans are encoded by highly conserved genes. For example at the core of metabolism, hexokinase, the enzyme that phosphorylates incoming glucose, and many of the proteins that transport glucose look strikingly similar. This similarity goes yet deeper, as hexokinase has two distinct functions both as an enzyme and as a sensor (“sensyme”), a duality that appears to be conserved from plants to fungi to animals (Frommer et al., 2003). In a second example, the identification of the first higher plant ammonium transporter allowed a function to be assigned for the first time to an important human locus – the Rhesus factor (Ninnemann et al., 1994; Marini et al., 1997). One of the most recent and striking examples of functional similarities was the finding that both plants and animals use carbonic anhydrase to sense carbon dioxide – in humans permitting champagne bubbles to be tasted, and in plants crucial for control over the gas exchange with the atmosphere (Frommer, 2010). McGary et al. (2010) found that plants and people share at least 48 functional modules; sets of genes that act in common to produce a phenotype. Many of these are disease-related. “There was a lot of screaming in the halls for that one [sic what was conceived as unexpected similarity]” as Edward Marcotte, a cancer researcher at the University of Texas, stated in the New York Times (Zimmer, 2010). This “deep homology” in functional networks, identified through the use of large datasets from the TAIR Arabidopsis database (www.arabidopsis.org/) argues strongly that research in plants can not only unravel the secrets of plants, but can guide research in metazoan organisms. It is apparently a consequence of evolution, where much remains to be learned about the first ancestors of multicellular green organisms and the mechanisms that had to evolve to allow for efficient photosynthesis, gas exchange, efficient mining of mineral nutrients and multicellularity.

Grand opportunities in physiology to address the grand challenges facing the planet

For people, plants can seem like aliens. Movements are typically slow, and many consider plants “slow and low life [sLow life]” (Hangarter, 2009). Their appearance and behavior are so different from ourselves that we are in awe when we learn that many of the central functions of plants and humans are encoded by highly conserved genes. For example at the core of metabolism, hexokinase, the enzyme that phosphorylates incoming glucose, and many of the proteins that transport glucose look strikingly similar. This similarity goes yet deeper, as hexokinase has two distinct functions both as an enzyme and as a sensor (“sensyme”), a duality that appears to be conserved from plants to fungi to animals (Frommer et al., 2003). In a second example, the identification of the first higher plant ammonium transporter allowed a function to be assigned for the first time to an important human locus – the Rhesus factor (Ninnemann et al., 1994; Marini et al., 1997). One of the most recent and striking examples of functional similarities was the finding that both plants and animals use carbonic anhydrase to sense carbon dioxide – in humans permitting champagne bubbles to be tasted, and in plants crucial for control over the gas exchange with the atmosphere (Frommer, 2010). McGary et al. (2010) found that plants and people share at least 48 functional modules; sets of genes that act in common to produce a phenotype. Many of these are disease-related. “There was a lot of screaming in the halls for that one [sic what was conceived as unexpected similarity]” as Edward Marcotte, a cancer researcher at the University of Texas, stated in the New York Times (Zimmer, 2010). This “deep homology” in functional networks, identified through the use of large datasets from the TAIR Arabidopsis database (www.arabidopsis.org/) argues strongly that research in plants can not only unravel the secrets of plants, but can guide research in metazoan organisms. It is apparently a consequence of evolution, where much remains to be learned about the first ancestors of multicellular green organisms and the mechanisms that had to evolve to allow for efficient photosynthesis, gas exchange, efficient mining of mineral nutrients and multicellularity.