SUPERMAN genes: uncovering a new function in the development of complex inflorescences.

The Arabidopsis SUPERMAN (SUP) gene and its orthologs in eudicots are crucial in regulating the number of reproductive floral organs. In Medicago truncatula, in addition to this function, a novel role in controlling meristem activity during compound inflorescence development was assigned to the SUP-ortholog (MtSUP). These findings led us to investigate whether the role of SUP genes in inflorescence development was legume-specific or could be extended to other eudicots.

strikes again in legumes.

The () gene was described in over 30 years ago. was classified as a cadastral gene required to maintain the boundaries between reproductive organs, thus controlling stamen and carpel number in flowers. We summarize the information on the characterization of orthologs in plant species other than Arabidopsis, focusing on the findings for the , the ortholog in the legume .

The tapetal tissue is essential for the maintenance of redox homeostasis during microgametogenesis in tomato.

The tapetum is a specialized layer of cells within the anther, adjacent to the sporogenous tissue. During its short life, it provides nutrients, molecules and materials to the pollen mother cells and microsporocytes, being essential during callose degradation and pollen wall formation. The interaction between the tapetum and sporogenous cells in Solanum lycopersicum (tomato) plants, despite its importance for breeding purposes, is poorly understood.

Is a Key Player in Pea Pollen Development Through the Modulation of Redox Homeostasis.

Redox homeostasis has been linked to proper anther and pollen development. Accordingly, plant cells have developed several Reactive Oxygen Species (ROS)-scavenging mechanisms to maintain the redox balance. Hemopexins constitute one of these mechanisms preventing heme-associated oxidative stress in animals, fungi, and plants.

Isolation and Functional Analysis of a -like MADS-Box Gene from Argan Tree ().

Argan trees () belong to a species native to southwestern Morocco, playing an important role in the environment and local economy. Argan oil extracted from kernels has a unique composition and properties. Argan trees were introduced in Tunisia, where hundreds of trees can be found nowadays.

MtSUPERMAN plays a key role in compound inflorescence and flower development in Medicago truncatula.

Legumes have unique features, such as compound inflorescences and a complex floral ontogeny. Thus, the study of regulatory genes in these species during inflorescence and floral development is essential to understand their role in the evolutionary origin of developmental novelties. The SUPERMAN (SUP) gene encodes a C2H2 zinc-finger transcriptional repressor that regulates the floral organ number in the third and fourth floral whorls of Arabidopsis thaliana.

Efficient evaluation of a gene containment system for poplar through early flowering induction.

The early flowering system HSP::AtFT allowed a fast evaluation of a gene containment system based on the construct PsEND1::barnase-barstar for poplar. Transgenic lines showed disturbed pollen development and sterility. Vertical gene transfer through pollen flow from transgenic or non-native plant species into their crossable natural relatives is a major concern.

Engineered Male Sterility by Early Anther Ablation Using the Pea Anther-Specific Promoter PsEND1.

Genetic engineered male sterility has different applications, ranging from hybrid seed production to bioconfinement of transgenes in genetic modified crops. The impact of this technology is currently patent in a wide range of crops, including legumes, which has helped to deal with the challenges of global food security. Production of engineered male sterile plants by expression of a ribonuclease gene under the control of an anther- or pollen-specific promoter has proven to be an efficient way to generate pollen-free elite cultivars.

The DOF Transcription Factor Regulates Vascular Tissue Formation During Ovary Development in Tomato.

The formation of fruits is an important step in the life cycle of flowering plants. The process of fruit development is highly regulated and involves the interaction of a complex regulatory network of genes in both space and time. To identify regulatory genes involved in fruit initiation in tomato we analyzed the transcriptomic profile of ovaries from the parthenocarpic transgenic line.

Enzymatic Assays and Enzyme Histochemistry of Feeding on Tomato Leaves.

Enzymes play a key role in insect-plant relationships. For a better understanding of these interactions, we analyzed digestive enzymes. Here, we describe a detailed protocol for the detection of trypsin and papain-like enzymes in larvae by enzyme histochemistry.

Functional Genomics and Genetic Control of Flower and Fruit Development in Medicago truncatula: An Overview.

A-, B-, and C-class genes code for MADS-box transcription factors required for floral organ identity in angiosperms. Other members of the family are also crucial to ensure proper carpel and fruit development. Development of genetic and genomic tools for Medicago truncatula has allowed its use as model system to study the genetic control of flower and fruit development in legumes.

Model Legumes: Functional Genomics Tools in Medicago truncatula.

Many researchers have sought along the last two decades a legume species that could serve as a model system for genetic studies to resolve specific developmental or metabolic processes that cannot be studied in other model plants. Nitrogen fixation, nodulation, compound leaf, inflorescence and plant architecture, floral development, pod formation, secondary metabolite biosynthesis, and other developmental and metabolic aspects are legume-specific or show important differences with those described in Arabidopsis thaliana, the most studied model plant. Mainly Medicago truncatula and Lotus japonicus were proposed in the 1990s as model systems due to their key attributes, diploid genome, autogamous nature, short generation times, small genome sizes, and both species can be readily transformed.

Grain and Forage Legumes: Nutritional Value and Agriculture Sustainability.

Humanity faces great challenges with respect to the use of energy, the production of food and feed, and the management of the Earth through sustainable practices. Agriculture can play a key role to give appropriate responses to these challenges. By the end of this century, human population will grow up to around 10,000 million people, meaning we must be able to produce food and feed for more than an additional number of 3300 million people.

Expression of two barley proteinase inhibitors in tomato promotes endogenous defensive response and enhances resistance to Tuta absoluta.

Background: Plants and insects have coexisted for million years and evolved a set of interactions which affect both organisms at different levels. Plants have developed various morphological and biochemical adaptations to cope with herbivores attacks. However, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) has become the major pest threatening tomato crops worldwide and without the appropriated management it can cause production losses between 80 to 100%.

Metabolic engineering to simultaneously activate anthocyanin and proanthocyanidin biosynthetic pathways in Nicotiana spp.

Proanthocyanidins (PAs), or condensed tannins, are powerful antioxidants that remove harmful free oxygen radicals from cells. To engineer the anthocyanin and proanthocyanidin biosynthetic pathways to de novo produce PAs in two Nicotiana species, we incorporated four transgenes to the plant chassis. We opted to perform a simultaneous transformation of the genes linked in a multigenic construct rather than classical breeding or retransformation approaches.

The parthenocarpic hydra mutant reveals a new function for a SPOROCYTELESS-like gene in the control of fruit set in tomato.

Fruit set is an essential process to ensure successful sexual plant reproduction. The development of the flower into a fruit is actively repressed in the absence of pollination. However, some cultivars from a few species are able to develop seedless fruits overcoming the standard restriction of unpollinated ovaries to growth.

Evolution by gene duplication of Medicago truncatula PISTILLATA-like transcription factors.

PISTILLATA (PI) is a member of the B-function MADS-box gene family, which controls the identity of both petals and stamens in Arabidopsis thaliana. In Medicago truncatula (Mt), there are two PI-like paralogs, known as MtPI and MtNGL9. These genes differ in their expression patterns, but it is not known whether their functions have also diverged.

Two euAGAMOUS genes control C-function in Medicago truncatula.

C-function MADS-box transcription factors belong to the AGAMOUS (AG) lineage and specify both stamen and carpel identity and floral meristem determinacy. In core eudicots, the AG lineage is further divided into two branches, the euAG and PLE lineages. Functional analyses across flowering plants strongly support the idea that duplicated AG lineage genes have different degrees of subfunctionalization of the C-function.

PsPMEP, a pollen-specific pectin methylesterase of pea (Pisum sativum L.).

Pectin methylesterases (PMEs) are a family of enzymes involved in plant reproductive processes such as pollen development and pollen tube growth. We have isolated and characterized PsPMEP, a pea (Pisum sativum L.) pollen-specific gene that encodes a protein with homology to PMEs.

Early anther ablation triggers parthenocarpic fruit development in tomato.

Fruit set and fruit development in tomato is largely affected by changes in environmental conditions, therefore autonomous fruit set independent of fertilization is a highly desirable trait in tomato. Here, we report the production and characterization of male-sterile transgenic plants that produce parthenocarpic fruits in two tomato cultivars (Micro-Tom and Moneymaker). We generated male-sterility using the cytotoxic gene barnase targeted to the anthers with the PsEND1 anther-specific promoter.

Functional specialization of duplicated AP3-like genes in Medicago truncatula.

The B-class of MADS box genes has been studied in a wide range of plant species, but has remained largely uncharacterized in legumes. Here we investigate the evolutionary fate of the duplicated AP3-like genes of a legume species. To obtain insight into the extent to which B-class MADS box gene functions are conserved or have diversified in legumes, we isolated and characterized the two members of the AP3 lineage in Medicago truncatula: MtNMH7 and MtTM6 (euAP3 and paleoAP3 genes, respectively).

Production of engineered long-life and male sterile Pelargonium plants.

Background: Pelargonium is one of the most popular garden plants in the world. Moreover, it has a considerable economic importance in the ornamental plant market. Conventional cross-breeding strategies have generated a range of cultivars with excellent traits.

VEGETATIVE1 is essential for development of the compound inflorescence in pea.

Unravelling the basis of variation in inflorescence architecture is important to understanding how the huge diversity in plant form has been generated. Inflorescences are divided between simple, as in Arabidopsis, with flowers directly formed at the main primary inflorescence axis, and compound, as in legumes, where they are formed at secondary or even higher order axes. The formation of secondary inflorescences predicts a novel genetic function in the development of the compound inflorescences.

Efficient transformation of Kalanchoe blossfeldiana and production of male-sterile plants by engineered anther ablation.

Engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. We have developed a reliable and efficient Agrobacterium-mediated protocol for the genetic transformation of different Kalanchoe blossfeldiana commercial cultivars. Transformation efficiency for cv.

Analysis of B function in legumes: PISTILLATA proteins do not require the PI motif for floral organ development in Medicago truncatula.

The B-class gene PISTILLATA (PI) codes for a MADS-box transcription factor required for floral organ identity in angiosperms. Unlike Arabidopsis, it has been suggested that legume PI genes contribute to a variety of processes, such as the development of floral organs, floral common petal-stamen primordia, complex leaves and N-fixing root nodules. Another interesting feature of legume PI homologues is that some of them lack the highly conserved C-terminal PI motif suggested to be crucial for function.