Stilbene synthase (STS) is the key enzyme leading to the biosynthesis of resveratrol. Recently we reported two R2R3-MYB transcription factor (TF) genes that regulate the stilbene biosynthetic pathway in grapevine: VviMYB14 and VviMYB15. These genes are strongly co-expressed with STS genes under a range of stress and developmental conditions, in agreement with the specific activation of STS promoters by these TFs. Genome-wide gene co-expression analysis using two separate transcriptome compendia based on microarray and RNA sequencing data revealed that WRKY TFs were the top TF family correlated with STS genes. On the basis of correlation frequency, four WRKY genes, namely VviWRKY03, VviWRKY24, VviWRKY43 and VviWRKY53, were further shortlisted and functionally validated. Expression analyses under both unstressed and stressed conditions, together with promoter-luciferase reporter assays, suggested different hierarchies for these TFs in the regulation of the stilbene biosynthetic pathway. In particular, VviWRKY24 seems to act as a singular effector in the activation of the VviSTS29 promoter, while VviWRKY03 acts through a combinatorial effect with VviMYB14, suggesting that these two regulators may interact at the protein level as previously reported in other species.

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been made public for more than 1 yr. They should also be useful and nonobvious to someone skilled in the art Since a 1980 Supreme Court decision, it is possible in the USA to (35 USC § 101, 102, 103) (U.S. House of Representaobtain a utility patent for crop cultivars and other life forms. Furthertives, 2002). more, it is also possible to obtain Plant Variety Protection (PVP) In 1999, the U.S. PTO awarded patent no. 5,894,079 for a cultivar. Among the awards of the United States Patent and Trademark Office and the USDA Plant PVP Office are a utility for the yellow-seeded cultivar Enola of common bean. patent and a PVP certificate, respectively, associated with a yellow-The main claim of this patent is the yellow color of the seeded bean (Phaseolus vulgaris L.), specifically the cultivar Enola. seed coat of Enola. According to the patent description These awards have been controversial because of, among several (Proctor, 1999), seeds of this cultivar had been obtained reasons, the perceived lack of novelty of the yellow seed color and as part of a mixed bag of seeds of different colors purthe cultivar itself. To check the origin of Enola, we fingerprinted a chased in Mexico in 1994. The yellow seeds were then representative sample of 56 domesticated common bean accessions, planted in a field in Colorado for 3 yr (1994-1996) after including a subsample of 24 cultivars with yellow seeds similar to those which a patent for this yellow-seeded variety was filed on of Enola. Fingerprinting was accomplished with amplified fragment 15 Nov. 1996. Furthermore, the Plant Variety Protection length polymorphisms (AFLP). Five EcoRI/MseI and five PstI/MseI (PVP) Office of the USDA issued PVP certificate no. primer combinations were used, which revealed 133 fragments. The 9700027 for cultivar Enola in 1999 (http://www.ars-grin. PstI/MseI primer combinations revealed a 3-fold larger number of gov/cgi-bin/npgs/html/acchtml.pl?1536394; verified 8 Janupolymorphic markers than the EcoRI/MseI primer combinations. ary 2004). The award of these intellectual property rights Most yellow-seeded beans, including Enola, were included in a tightly has generated widespread attention in the media (New knit subgroup of the Andean gene pool. Enola was most closely related to the pre-existing Mexican cultivar Azufrado Peruano 87.

The production of eggs with the sporophytic chromosome number (2n eggs) in diploid alfalfa (Medicago spp.) is mainly associated with the absence of cytokinesis after restitutional meiosis. The formation of 2n eggs through diplosporic apomeiosis has also been documented in a diploid mutant of M. sativa subsp. falcata (L.) Arcang. (2n = 2x = 16), named PG-F9. Molecular tagging of 2n-egg formation appears to be an essential step towards marker-assisted breeding and map-based cloning strategies aimed at investigating and manipulating reproductive mutants of the M. sativa complex. We made controlled crosses between PG-F9 and three wild type plants of M. sativa subsp. coerulea (Less.) Schm. (2n = 2x = 16) and then hand-pollinated the F1 progenies with tetraploid plants of M. sativa subsp. sativa L. (2n = 4x = 32). As a triploid embryo block prevents the formation of 3x progenies in alfalfa because of endosperm imbalance, and owing to the negligible selfing rate, seed set in 2x-4x crosses was used to discriminate the genetic capacity for 2n-egg production. F1 plants that exhibited null or very low seed sets were classified as normal egg producers and plants with high seed sets as 2n-egg producers. A bulked segregant analysis (BSA) with RAPD (random amplified polymorphic DNA), ISSR (inter-simple sequence repeat), and AFLP (amplified fragment length polymorphism) markers was employed to identify a genetic linkage group related to the 2n-egg trait using one of the three F1 progenies. This approach enabled us to detect a paternal ISSR marker of 610 bp, generated by primer (CA)8-GC, located 9.8 cM from a putative gene (termed Tne1, two-n-eggs) that in its recessive form determines 2n eggs and a 30% recombination genomic window surrounding the target locus. Eight additional RAPD and AFLP markers, seven of maternal, and one of paternal origin, significantly co-segregated with the trait under investigation. The minimum number of quantitative trait loci (QTLs) controlling seed set in 2x-4x crosses was estimated by ANOVA and regression analysis. Four maternal and three paternal independent molecular markers significantly affected the trait. A paternal RAPD marker allele, mapped in the same linkage group of Tne1, explained 43% of the variation for seed set in 2x-4x crosses indicating the presence of a major QTL. A map of the PG-F9 chromosome regions carrying the minor genes that determine the expression level of 2n eggs was constructed using selected RAPD and AFLP markers. Two of these genes were linked to previously mapped RFLP loci belonging to groups 1 and 8. Molecular and genetic evidence support the involvement of at least five genes.

Abstract:The MOB family includes a group of cell cycle-associated proteins highly conserved throughout eukaryotes, whose founding members are implicated in mitotic exit and co-ordination of cell cycle progression with cell polarity and morphogenesis. Here we report the characterization and evolution of the MOB domain-containing proteins as inferred from the 43 eukaryotic genomes so far sequenced. We show that genes for Mob-like proteins are present in at least 41 of these genomes, confi rming the universal distribution of this protein family and suggesting its prominent biological function. The phylogenetic analysis reveals fi ve distinct MOB domain classes, showing a progressive expansion of this family from unicellular to multicellular organisms, reaching the highest number in mammals. Plant Mob genes appear to have evolved from a single ancestor, most likely after the loss of one or more genes during the early stage of Viridiplantae evolutionary history. Three of the Mob classes are widespread among most of the analyzed organisms. The possible biological and molecular function of Mob proteins and their role in conserved signaling pathways related to cell proliferation, cell death and cell polarity are also presented and critically discussed.

Cannabis (Cannabis sativa L.) is an influential yet controversial agricultural plant with a very long and prominent history of recreational, medicinal, and industrial usages. Given the importance of this species, we deepened some of the main challenges-along with potential solutions-behind the breeding of new cannabis cultivars. One of the main issues that should be fixed before starting new breeding programs is the uncertain taxonomic classification of the two main taxa (e.g., indica and sativa) of the Cannabis genus. We tried therefore to examine this topic from a molecular perspective through the use of DNA barcoding. Our findings seem to support a unique species system (C. sativa) based on two subspecies: C. sativa subsp. sativa and C. sativa subsp. indica. The second key issue in a breeding program is related to the dioecy behavior of this species and to the comprehension of those molecular mechanisms underlying flower development, the main cannabis product. Given the role of MADS box genes in flower identity, we analyzed and reorganized all the genomic and transcriptomic data available for homeotic genes, trying to decipher the applicability of the ABCDE model in Cannabis. Finally, reviewing the limits of the conventional breeding methods traditionally applied for developing new varieties, we proposed a new breeding scheme for the constitution of F 1 hybrids, without ignoring the indisputable contribution offered by genomics. In this sense, in parallel, we resumed the main advances in the genomic field of this species and, ascertained the lack of a robust set of SNP markers, provided a discriminant and polymorphic panel of SSR markers as a valuable tool for future marker assisted breeding programs.

The introgression of apomixis in major seed crops, would guarantee self-seeding of superior heterotic seeds over generations. In the grass species Paspalum simplex , apomixis is controlled by a single locus in which recombination is blocked. In the perspective of isolating the genetic determinants of apomixis, we report data on sequencing, in silico mapping and expression analysis of some of the genes contained in two cloned genomic regions of the apomixis locus of P . simplex . In silico mapping allowed us to identify a conserved synteny group homoeologous to the apomixis locus, located on a telomeric position of chromosomes 12, 8, 3 and 4 of rice, Sorghum bicolor , Setaria italica and Brachypodium distachyum , respectively, and on a more centromeric position of maize chromosome 1. Selected genes of the apomixis locus expressed sense and antisense transcripts in reproductively committed cells of sexual and apomictic ovules. Some of the genes considered here expressed apomixis-specific allelic variants which showed partial non-overlapping expression patterns with alleles shared by sexual and apomictic reproductive phenotypes. Our findings open new routes for the isolation of the genetic determinants of apomixis and, in perspective, for its introgression in crop grasses.

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