Biology subjects

Schmöckel, S. M.

Publications and source records attributed to Schmöckel, S. M..

5 recordsLinked to original sources

bioRxiv2023

Learning from the expert: studying Salicornia to understand salinity tolerance

Salinity remains a major inhibitor of crop production in irrigated and marginal lands. The identification of genes involved in salinity tolerance has been predominantly limited to model plants and crop species. However, plants naturally adapted to highly saline environments can provide key insights into mechanisms of salinity tolerance. Plants of the genus Salicornia grow in coastal salt marshes, and their growth is even stimulated by NaCl - much can be learnt from them. We generated genome sequences of two Salicornia species and studied the transcriptomic and proteomic responses of Salicornia bigelovii to NaCl. Through the generation of subcellular membrane proteomes, we found that SbiSOS1, a homolog of the well-known SALT-OVERLY-SENSITIVE 1 (SOS1) protein, appears to localize to the tonoplast, where it could be involved in mediating Na+ translocation into the vacuole to prevent toxicity in the cytosol. We identified 11 proteins of interest which, when expressed in yeast, altered salinity tolerance. One of these proteins, SbiSALTY, substantially improves yeast growth on saline media. Structural characterization using NMR showed it to be an intrinsically disordered protein and to localize to the endoplasmic reticulum in planta, where it could interact with ribosomes and RNA, potentially stabilizing or protecting them during salt stress. The study and understanding of the molecular mechanisms providing high salinity tolerance in S. bigelovii is likely to provide significant insights for improving salinity tolerance of crop plants.

plant biology↗

bioRxiv2021

The diversity of quinoa morphological traits and seed metabolic composition

Quinoa (Chenopodium quinoa Willd.) is an herbaceous annual crop of the amaranth family (Amaranthaceae). It is increasingly cultivated for its nutritious grains, which are rich in protein and essential amino acids, lipids, and minerals. Quinoa exhibits a high tolerance towards various abiotic stresses including drought and salinity, which supports its agricultural cultivation under climate change conditions. The use of quinoa grains is compromised by anti-nutritional saponins, a terpenoid class of secondary metabolites deposited in the seed coat; their removal before consumption requires extensive washing, an economically and environmentally unfavorable process; or their accumulation can be reduced through breeding. In this study, we analyzed the seed metabolomes, including amino acids, fatty acids, and saponins, from 471 quinoa cultivars, including two related species, by liquid chromatography - mass spectrometry. Additionally, we determined a large number of agronomic traits including biomass, flowering time, and seed yield. The results revealed considerable diversity between genotypes and provide a knowledge base for future breeding or genome editing of quinoa. O_TBL View this table: org.highwire.dtl.DTLVardef@160e784org.highwire.dtl.DTLVardef@ff8bd1org.highwire.dtl.DTLVardef@13446daorg.highwire.dtl.DTLVardef@11796eeorg.highwire.dtl.DTLVardef@1b607b8_HPS_FORMAT_FIGEXP M_TBL C_TBL

plant biology↗

bioRxiv2020

Genetic variation for tolerance to the downy mildew pathogen Peronospora variabilis in genetic resources of quinoa (Chenopodium quinoa)

BackgroundQuinoa (Chenopodium quinoa Willd.) is an ancient grain crop that is tolerant to abiotic stress and has favorable nutritional properties. Downy mildew is the main disease of quinoa and is caused by infections of the biotrophic oomycete Peronospora variabilis Gaum. Since the disease causes major yield losses, identifying sources of downy mildew tolerance in genetic resources and understanding its genetic basis are important goals in quinoa breeding. ResultsWe infected 132 South American genotypes, three Danish cultivars and the weedy relative C. album with a single isolate of P. variabilis under greenhouse conditions and observed a large variation in disease traits like severity of infection, which ranged from 5% to 83%. Linear mixed models revealed a significant effect of genotypes on disease traits with high heritabilities (0.72 to 0.81). Factors like altitude at site of origin or seed saponin content did not correlate with mildew tolerance, but stomatal width was weakly correlated with severity of infection. Despite the strong genotypic effects on mildew tolerance, genome-wide association mapping with 88 genotypes failed to identify significant marker-trait associations indicating a polygenic architecture of mildew tolerance. ConclusionsThe strong genetic effects on mildew tolerance allow to identify genetic resources, which are valuable sources of resistance in future quinoa breeding.

plant biology↗

bioRxiv2019

Genome wide identification of NAC transcription factors and their role in abiotic stress tolerance in Chenopodium quinoa

Chenopodium quinoa Willd. (quinoa) is a pseudocereal with high nutritional value and relatively high tolerance to several abiotic stresses, including water deficiency and salt stress, making it a suitable plant for the study of mechanisms of abiotic stress tolerance. NAC (NAM, ATAF and CUC) transcription factors are involved in a range of plant developmental processes and in the response of plants to biotic and abiotic stresses. In the present study, we perform a genome-wide comprehensive analysis of the NAC transcription factor gene family in quinoa. In total, we identified 107 quinoa NAC transcription factor genes, distributed equally between sub-genomes A and B. They are phylogenetically clustered into two major groups and 18 subgroups. Almost 75% of the identified CqNAC genes were duplicated two to seven times and the remaining 25% of the CqNAC genes were found as a single copy. We analysed the transcriptional responses of the identified quinoa NAC TF genes in response to various abiotic stresses. The transcriptomic data revealed 28 stress responsive CqNAC genes, where their expression significantly changed in response to one or more abiotic stresses, including salt, water deficiency, heat and phosphate starvation. Among these stress responsive NACs, some were previously known to be stress responsive in other species, indicating their potentially conserved function in response to abiotic stress across plant species. Six genes were differentially expressed specifically in response to phosphate starvation but not to other stresses, and these genes may play a role in controlling plant responses to phosphate deficiency. These results provide insights into quinoa NACs that could be used in the future for genetic engineering or molecular breeding.

plant biology↗

bioRxiv2017

The genome sequence of the wild tomato Solanum pimpinellifolium provides insights into salinity tolerance

Solanum pimpinellifolium, a wild relative of cultivated tomato, offers a wealth of breeding potential for several desirable traits such as tolerance to abiotic and biotic stresses. Here, we report the genome and annotation of S. pimpinellifolium LA0480. The LA0480 genome size (811 Mb) and the number of annotated genes (25,970) are within the range observed for other sequenced tomato species. We developed and utilized the Dragon Eukaryotic Analyses Platform (DEAP) to functionally annotate the LA0480 protein-coding genes. Additionally, we used DEAP to compare protein function between S. pimpinellifolium and cultivated tomato. Our data suggest enrichment in genes involved in biotic and abiotic stress responses. Moreover, we present phenotypic data from one field experiment that demonstrate a greater salinity tolerance for fruit-and yield-related traits in S. pimpinellifolium compared with cultivated tomato. To understand the genomic basis for these differences in S. pimpinellifolium and S. lycopersicum, we analyzed 15 genes that have previously been shown to mediate salinity tolerance in plants. We show that S. pimpinellifolium has a higher copy number of the inositol-3-phosphate synthase and phosphatase genes, which are both key enzymes in the production of inositol and its derivatives. Moreover, our analysis indicates that changes occurring in the inositol phosphate pathway may contribute to the observed higher salinity tolerance in LA0480. Altogether, our work provides essential resources to understand and unlock the genetic and breeding potential of S. pimpinellifolium, and to discover the genomic basis underlying its environmental robustness.

plant biology↗