•We revisit the concept of the Ancestral Crucifer Karyotype (ACK) and the definition of a revised set of 22 conserved genomic blocks across the Brassicaceae family including Arabidopsis and crop ...Brassicas.•We review how the ACK has been utilized for the analysis of a remarkable thirty-five crucifer genomes to date.•We discuss mechanisms of genome reorganization leading to block shuffling and breakage including the role of ancient polyploidy.
A decade ago the concept of the Ancestral Crucifer Karyotype (ACK) and the definition of 24 conserved genomic blocks was presented. Subsequently, 35 cytogenetic reconstructions and/or draft genome sequences of crucifer species (members of the Brassicaceae family) have been analyzed in the context of this system; placing crucifers at the forefront of plant phylogenomics. In this review, we highlight how the ACK and genomic blocks have facilitated and guided genomic analysis of crucifers in the last 10 years and provide an update of this robust model.
Pollen-pistil interactions establish interspecific/intergeneric pre-zygotic hybridization barriers in plants. The rejection of undesired pollen at the stigma is crucial to avoid outcrossing but can ...be overcome with the support of mentor pollen. The mechanisms underlying this hybridization barrier are largely unknown. Here, in Arabidopsis, we demonstrate that receptor-like kinases FERONIA/CURVY1/ANJEA/HERCULES RECEPTOR KINASE 1 and cell wall proteins LRX3/4/5 interact on papilla cell surfaces with autocrine stigmatic RALF1/22/23/33 peptide ligands (sRALFs) to establish a lock that blocks the penetration of undesired pollen tubes. Compatible pollen-derived RALF10/11/12/13/25/26/30 peptides (pRALFs) act as a key, outcompeting sRALFs and enabling pollen tube penetration. By treating Arabidopsis stigmas with synthetic pRALFs, we unlock the barrier, facilitating pollen tube penetration from distantly related Brassicaceae species and resulting in interspecific/intergeneric hybrid embryo formation. Therefore, we uncover a “lock-and-key” system governing the hybridization breadth of interspecific/intergeneric crosses in Brassicaceae. Manipulating this system holds promise for facilitating broad hybridization in crops.
Display omitted
•Stigmatic sRALFs establish an intergeneric barrier “lock” to prevent hybridization•sRALFs act through CrRLK1L receptor complexes and LRX cell wall proteins•As a “key,” compatible pRALFs outcompete sRALFs to unlatch the lock•Application of synthetic pRALFs breaks the stigmatic barrier, enabling plant outcrosses
A stigmatic intergeneric hybridization barrier is established via sRALF peptides/CrRLK1L receptors in concert with LRX proteins to block the penetration of incompatible pollen tubes, which can be overcome by pRALF peptides derived from compatible pollen.
•The complete cp genome of S. alba was obtained by the PacBio and Illumina reads.•Codon usage this cp genome revealed a preferential use of Leu with the A/U ending.•S. alba showed a close ...relationship with important Brassica and Raphanus species.•The genes for “Cytochrome b/f complex” were under the lowest selection pressure.
As a member of the large Brassicaceae family, yellow mustard (Sinapis alba L.) has been used as an important gene pool for the genetic improvement of cash crops in Brassicaceae. Understanding the phylogenetic relationship between Sinapis alba (S. alba) and other Brassicaceae crops can provide guidance on the introgression of its favorable alleles into related species. The chloroplast (cp) genome is an ideal model for assessing genome evolution and the phylogenetic relationships of complex angiosperm families. Herein, we de novo assembled the complete cp genome of S. alba by integrating the PacBio and Illumina sequencing platforms. A 153,760 bp quadripartite cycle without any gap was obtained, including a pair of inverted repeats (IRa and IRb) of 26,221 bp, separated by a large single copy (LSC) region of 83,506 bp and a small single copy (SSC) region of 17,821 bp. A total of 78 protein-coding genes, 30 tRNA genes, and four rRNA genes were identified in this cp genome, as were 89 simple sequence repeat (SSR) loci of 18 types. The codon usage analysis revealed a preferential use of the Leu codon with the A/U ending. The phylogenetic analysis using 82 Brassicaceae species demonstrated that S. alba had a close relationship with important Brassica and Raphanus species; moreover, it likely originated from a separate evolutionary pathway compared with the congeneric Sinapis arvensis. The synonymous (Ks) and non-synonymous (Ks) substitution rate analysis showed that genes encoding “Subunits of cytochrome b/f complex” were under the lowest purifying selection pressure, whereas those associated with “Maturase”, “Subunit of acetyl-CoA”, and “Subunits of NADH-dehydrogenase” underwent relatively higher purifying selection pressures. Our results provide valuable information for fully utilizing the S. alba cp genome as a potential genetic resource for the genetic improvement of Brassica and Raphanus species.
Despite the central importance of noncoding DNA to gene regulation and evolution, understanding of the extent of selection on plant noncoding DNA remains limited compared to that of other organisms. ...Here we report sequencing of genomes from three Brassicaceae species (Leavenworthia alabamica, Sisymbrium irio and Aethionema arabicum) and their joint analysis with six previously sequenced crucifer genomes. Conservation across orthologous bases suggests that at least 17% of the Arabidopsis thaliana genome is under selection, with nearly one-quarter of the sequence under selection lying outside of coding regions. Much of this sequence can be localized to approximately 90,000 conserved noncoding sequences (CNSs) that show evidence of transcriptional and post-transcriptional regulation. Population genomics analyses of two crucifer species, A. thaliana and Capsella grandiflora, confirm that most of the identified CNSs are evolving under medium to strong purifying selection. Overall, these CNSs highlight both similarities and several key differences between the regulatory DNA of plants and other species.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Summary
Two Brassicaceae species, Physaria fendleri and Camelina sativa, are genetically very closely related to each other and to Arabidopsis thaliana. Physaria fendleri seeds contain over 50% ...hydroxy fatty acids (HFAs), while Camelina sativa and Arabidopsis do not accumulate HFAs. To better understand how plants evolved new biochemical pathways with the capacity to accumulate high levels of unusual fatty acids, transcript expression and protein sequences of developing seeds of Physaria fendleri, wild‐type Camelina sativa, and Camelina sativa expressing a castor bean (Ricinus communis) hydroxylase were analyzed. A number of potential evolutionary adaptations within lipid metabolism that probably enhance HFA production and accumulation in Physaria fendleri, and, in their absence, limit accumulation in transgenic tissues were revealed. These adaptations occurred in at least 20 genes within several lipid pathways from the onset of fatty acid synthesis and its regulation to the assembly of triacylglycerols. Lipid genes of Physaria fendleri appear to have co‐evolved through modulation of transcriptional abundances and alterations within protein sequences. Only a handful of genes showed evidence for sequence adaptation through gene duplication. Collectively, these evolutionary changes probably occurred to minimize deleterious effects of high HFA amounts and/or to enhance accumulation for physiological advantage. These results shed light on the evolution of pathways for novel fatty acid production in seeds, help explain some of the current limitations to accumulation of HFAs in transgenic plants, and may provide improved strategies for future engineering of their production.
Significance Statement
Comparison of protein sequences and transcript expression from developing seeds of Physaria fendleri that accumulate high amounts of hydroxy FAs, to Camelina sativa, a closely related plant that does not accumulate hydroxy FAs revealed multiple genes, many of which have not been previously considered, that likely co‐evolved to enable hydroxy FA accumulation in Physaria. These genes provide new strategies to improve the ability of transgenic commodity crops to accumulate these and other value‐added oils.
Bacteria living on and in leaves and roots influence many aspects of plant health, so the extent of a plant's genetic control over its microbiota is of great interest to crop breeders and ...evolutionary biologists. Laboratory-based studies, because they poorly simulate true environmental heterogeneity, may misestimate or totally miss the influence of certain host genes on the microbiome. Here we report a large-scale field experiment to disentangle the effects of genotype, environment, age and year of harvest on bacterial communities associated with leaves and roots of Boechera stricta (Brassicaceae), a perennial wild mustard. Host genetic control of the microbiome is evident in leaves but not roots, and varies substantially among sites. Microbiome composition also shifts as plants age. Furthermore, a large proportion of leaf bacterial groups are shared with roots, suggesting inoculation from soil. Our results demonstrate how genotype-by-environment interactions contribute to the complexity of microbiome assembly in natural environments.
Symbiosis and the social network of higher plants Venkateshwaran, Muthusubramanian; Volkening, Jeremy D; Sussman, Michael R ...
Current opinion in plant biology,
02/2013, Letnik:
16, Številka:
1
Journal Article
Recenzirano
► Most plants associate with arbuscular mycorrhizal fungi using an ancient and highly conserved SYM pathway. ► Most of this pathway has been lost in some plant families including the Brassicaceae. ► ...This SYM pathway has been usurped by some plant families such as the legumes to instead also associate with nitrogen-fixing bacteria. ► The possibility of manipulating this SYM pathway to engineer more efficient associations between nonleguminous crops and nitrogen-fixing bacteria is discussed.
In the Internet era, communicating with friends and colleagues via social networks constitutes a significant proportion of our daily activities. Similarly animals and plants also interact with many organisms, some of which are pathogens and do no good for the plant, while others are beneficial symbionts. Almost all plants indulge in developing social networks with microbes, in particular with arbuscular mycorrhizal fungi, and emerging evidence indicates that most employ an ancient and widespread central ‘social media’ pathway made of signaling molecules within what is called the SYM pathway. Some plants, like legumes, are particularly active recruiters of friends, as they have established very sophisticated and beneficial interactions with nitrogen-fixing bacteria, also via the SYM pathway. Interestingly, many members of the Brassicaceae, including the model plant Arabidopsis thaliana, seem to have removed themselves from this ancestral social network and lost the ability to engage in mutually favorable interactions with arbuscular mycorrhizal fungi. Despite these generalizations, recent studies exploring the root microbiota of A. thaliana have found that in natural conditions, A. thaliana roots are colonized by many different bacterial species and therefore may be using different and probably more recent ‘social media’ for these interactions. In general, recent advances in the understanding of such molecular machinery required for plant–symbiont associations are being obtained using high throughput genomic profiling strategies including transcriptomics, proteomics and metabolomics. The crucial mechanistic understanding that such data reveal may provide the infrastructure for future efforts to genetically manipulate crop social networks for our own food and fiber needs.
Drought poses a serious threat to oilseed crops by lowering yield and crop failures under prolonged spells. A multi-year field investigation was conducted to enhance the drought tolerance in four ...genotypes of Camelina and canola by selenium (Se) application. The principal aim of the research was to optimize the crop yield by eliciting the physio-biochemical attributes by alleviating the adverse effects of drought stress. Both crops were cultivated under control (normal irrigation) and drought stress (skipping irrigation at stages i.e., vegetative and reproductive) conditions. Four different treatments of Se viz., seed priming with Se (75 μM), foliar application of Se (7.06 μM), foliar application of Se + Seed priming with Se (7.06 μM and 75 μM, respectively) and control (without Se), were implemented at the vegetative and reproductive stages of both crops. Sodium selenite (Na
SeO
), an inorganic compound was used as Se sources for both seed priming and foliar application. Data regarding physiochemical, antioxidants, and yield components were recorded as response variables at crop maturity. Results indicated that WP, OP, TP, proline, TSS, TFAA, TPr, TS, total chlorophyll contents, osmoprotectant (GB, anthocyanin, TPC, and flavonoids), antioxidants (APX, SOD, POD, and CAT), and yield components (number of branches per plant, thousand seed weight, seed, and biological yields were significantly improved by foliar Se + priming Se in both crops under drought stress. Moreover, this treatment was also helpful in boosting yield attributes under irrigated (non-stress) conditions. Camelina genotypes responded better to Se application as seed priming and foliar spray than canola for both years. It has concluded that Se application (either foliar or priming) can potentially alleviate adverse effects of drought stress in camelina and canola by eliciting various physio-biochemicals attributes under drought stress. Furthermore, Se application was also helpful for crop health under irrigated condition.
Self-incompatibility in plants Takayama, Seiji; Isogai, Akira
Annual review of plant biology,
01/2005, Letnik:
56, Številka:
1
Journal Article
Recenzirano
Sexual reproduction in many flowering plants involves self-incompatibility (SI), which is one of the most important systems to prevent inbreeding. In many species, the self-/nonself-recognition of SI ...is controlled by a single polymorphic locus, the S-locus. Molecular dissection of the S-locus revealed that SI represents not one system, but a collection of divergent mechanisms. Here, we discuss recent advances in the understanding of three distinct SI mechanisms, each controlled by two separate determinant genes at the S-locus. In the Brassicaceae, the determinant genes encode a pollen ligand and its stigmatic receptor kinase; their interaction induces incompatible signaling(s) within the stigma papilla cells. In the Solanaceae-type SI, the determinants are a ribonuclease and an F-box protein, suggesting the involvement of RNA and protein degradation in the system. In the Papaveraceae, the only identified female determinant induces a Ca2+-dependent signaling network that ultimately results in the death of incompatible pollen.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Vegetable oils (VO) are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA). However, oilseed crops ...can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar) were fed for 11-weeks with one of three experimental diets containing either fish oil (FO), wild-type Camelina oil (WCO) or transgenic Camelina oil (DCO) as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
