Plant sciences

  • Article
    | Open Access

    To explore the nature of wild and cultivated mandarins, the authors carry out genomic analysis of diverse east Asian citrus. The discovery of a wild species Citrus ryukyuensis native to the Ryukyu islands and a new population of wild mainland Asian mandarin explains the origin and diversity of mandarins and their ability to reproduce apomictically.

    • Guohong Albert Wu
    • , Chikatoshi Sugimoto
    •  & Daniel S. Rokhsar
  • Article
    | Open Access

    Gravitropism is the process by which plants perceive and respond to gravity. Here the authors identify a minus-end-directed kinesin required for gravity-triggered actin filament rearrangement and negative gravitropic response in the moss Physcomitrella patens, thus linking a microtubule-based cellular motor to gravitropism via actin.

    • Yufan Li
    • , Zhaoguo Deng
    •  & Haodong Chen
  • Article
    | Open Access

    Plant sulfate transporters mediate absorption and distribution of sulfate. Here the authors present functional assays and a cryo-EM structure of the Arabidopsis SULTR4;1 transporter identifying key domains for dimerization, substrate binding and coupling of transport activity to a proton gradient.

    • Lie Wang
    • , Kehan Chen
    •  & Ming Zhou
  • Article
    | Open Access

    HAP2 is essential for gamete fusion during fertilization and is conserved among eukaryotes. Here the authors show that species-specific adhesion between Chlamydomonas plus and minus gametes initiates HAP2 to undergo a fusogenic conformational change into homotrimers via a molecular mechanism akin to that of enveloped viruses.

    • Jun Zhang
    • , Jennifer F. Pinello
    •  & William J. Snell
  • Article
    | Open Access

    Rare earth elements are widely used in agriculture to promote plant growth. Here the authors show that aerial application of a rare earth element to the leaves triggers a graft-transmissible, RbohD- and jasmonic acid-dependent systemic signal that triggers endocytosis and mineral nutrient uptake in roots.

    • Mengzhu Cheng
    • , Lihong Wang
    •  & Zhenbiao Yang
  • Article
    | Open Access

    The apical style in Arabidopsis is formed following a bilateral-to-radial symmetry transition in the gynoecium. Here the authors show that the final step in style radialization is coordinated by the adaxial regulators HAT3 and ATHB4, which are induced by the SPT and HEC transcription factors.

    • Monica Carabelli
    • , Luana Turchi
    •  & Laila Moubayidin
  • Article
    | Open Access

    MORC ATPases are required for transposable element silencing and heterochromatin condensation in plants and animals. Here the authors show that Arabidopsis MORCs colocalize with sites of RNA-directed DNA methylation and provide evidence that they act as molecular tethers to efficiently establish DNA methylation.

    • Yan Xue
    • , Zhenhui Zhong
    •  & Steven E. Jacobsen
  • Article
    | Open Access

    Welwitschia mirabilis is a unique plant that only has two leaves, but it can survive in hostile conditions of the African desert. Here, the authors report its chromosome-level genome assembly and discuss how gene function and regulation have given rise to its unique morphology and environmental adaptions.

    • Tao Wan
    • , Zhiming Liu
    •  & Qingfeng Wang
  • Article
    | Open Access

    Chloroplast development and brassinosteroid (BR) signaling both regulate plant photomorphogenesis. Here the authors show that DAY, a DnaJ-like domain-containing membrane protein, regulates both processes by binding and stabilizing both BRI1, the BR receptor, and POR, a key enzyme in chlorophyll biosynthesis.

    • Ho-Seok Lee
    • , Ilyeong Choi
    •  & Hyun-Sook Pai
  • Article
    | Open Access

    Diploid potatoes are typically self-incompatible, complicating efforts to breed diploid cultivars. Here the authors report map-based cloning of the S-locus inhibitor (Sli) gene in potato which encodes a non S-locus F-box protein that is expressed in pollen and can functions like a general S-RNase inhibitor to overcome self-incompatibility.

    • Ling Ma
    • , Chunzhi Zhang
    •  & Yi Shang
  • Article
    | Open Access

    Pecan is an important specialty crop that has experienced extensive interspecific hybridization and nearly-obligate outcrossing. Here, the authors assemble diploid genomes of four outbred genotypes, identify interspecific introgressions through comparative genomics analyses, and map QTLs associated with pest resistance.

    • John T. Lovell
    • , Nolan B. Bentley
    •  & Jennifer J. Randall
  • Article
    | Open Access

    Bacterial pathogens can subvert host cell processes through secreted proteins but the precise mechanisms and repertoire of proteins remains unclear. Here the authors report that a bacterial effector protein of Xanthomonas campestris, XopR, undergoes liquid-liquid phase separation to hijack the host cell actin cytoskeleton.

    • He Sun
    • , Xinlu Zhu
    •  & Yansong Miao
  • Article
    | Open Access

    The LEC1 transcription factor is expressed in both embryo and endosperm during seed development. Here the authors show that LEC1 expression in the endosperm is necessary and sufficient for embryo maturation and that LEC1 protein is trafficked to the embryo to activate seed maturation.

    • Jingpu Song
    • , Xin Xie
    •  & Yuhai Cui
  • Article
    | Open Access

    The evolutionary and domestication history of apricots is poorly understood. Here, the authors provide four apricot high-quality genome assemblies, the genomes of 578 accessions from natural and cultivated populations, and show that Chinese and European apricots constitute two different gene pools, resulting from independent domestication events.

    • Alexis Groppi
    • , Shuo Liu
    •  & Véronique Decroocq
  • Article
    | Open Access

    It is currently thought that the thylakoid proteins PGRL1 and PGR5 form a complex to mediate cyclic electron flow (CEF) around photosystem I. Here the authors show that CEF can in fact be mediated by PGR5 alone and that PGRL1 and the homologous PGRL2 modify the process by modulating PGR5 activity and stability.

    • Thilo Rühle
    • , Marcel Dann
    •  & Dario Leister
  • Article
    | Open Access

    Beneficial plant-microbe interactions are common in nature, but direct evidence for the evolution of mutualism is scarce. Here, Li et al. experimentally evolve a rhizospheric bacterium and find that it can evolve into a mutualist on a relatively short timescale.

    • Erqin Li
    • , Ronnie de Jonge
    •  & Alexandre Jousset
  • Article
    | Open Access

    Plants undergo morphological changes collectively termed thermomorphogenesis when exposed to elevated temperature. Here the authors show that the SPA1 kinase regulates distinct thermomorphogenic responses according to tissue type by interactions with PIF4 and HY5 in shoots and roots, respectively.

    • Sanghwa Lee
    • , Wenli Wang
    •  & Enamul Huq
  • Article
    | Open Access

    Blue light penetrates deeper than red light in ocean, thus blue light sensing is critical for adaptation to marine environments. Here, the authors report the genome of Pyconococcus provasolii and identify a chimeric dual orange/far-red and blue light receptor composed of a phytochrome and a cryptochrome by analyzing the marine metagenomes.

    • Yuko Makita
    • , Shigekatsu Suzuki
    •  & Minami Matsui
  • Article
    | Open Access

    Longhua Shui Mi (LHSM) is a representative of the Chinese Cling peaches that have been central in global peach genetic improvement. Here, the authors assemble the genome of LHSM and show convergent selection for sweetness yet divergent selection for acidity in eastern vs. western cultivars through population genomics analyses.

    • Yang Yu
    • , Jiantao Guan
    •  & Hua Xie
  • Article
    | Open Access

    It is unclear whether climate driven phenological shifts of tundra plants are consistent across the plant growing season. Here the authors analyse data from a network of field warming experiments in Arctic and alpine tundra, finding that warming differentially affects the timing and duration of reproductive and vegetative phenology.

    • Courtney G. Collins
    • , Sarah C. Elmendorf
    •  & Katharine N. Suding
  • Article
    | Open Access

    Camptothecin is a monoterpene indole alkaloid with anti-tumor activity. Here, the authors assemble the genome of the camptothecin producing plant Camptotheca acuminata and provide insights into the evolutionary origin of camptothecin biosynthesis by comparing to the vinblastine and vincristine biosynthetic pathway in Catharanthus roseus.

    • Minghui Kang
    • , Rao Fu
    •  & Jianquan Liu
  • Article
    | Open Access

    Cyanobacterial thylakoid membranes host the molecular machinery for the light-dependent reactions of photosynthesis and respiratory electron flow. Here, the authors show that newly synthesized thylakoids emerge between the plasma membrane and pre-existing thylakoids and describe the time-dependent assembly process of photosynthetic complexes.

    • Tuomas Huokko
    • , Tao Ni
    •  & Lu-Ning Liu
  • Article
    | Open Access

    Molecular phylogenies are traditionally based on sequence variation, but genome rearrangements also contain phylogenetic information. Here, Zhao et al. develop an approach to reconstruct phylogenies based on microsynteny and illustrate it with a reconstruction of the angiosperm phylogeny.

    • Tao Zhao
    • , Arthur Zwaenepoel
    •  & Yves Van de Peer
  • Article
    | Open Access

    Moderate heat stress primes plants to acquire tolerance to subsequent, more severe heat stress. Here the authors show that the HSFA3 transcription factor forms a heteromeric complex with HSFA2 to sustain activated transcription of genes required for acquired thermotolerance by promoting H3K4 hyper-methylation.

    • Thomas Friedrich
    • , Vicky Oberkofler
    •  & Isabel Bäurle
  • Article
    | Open Access

    Light promotes stomatal development in plants. Here Wang et al. show that light stimulates stomatal development via the HY5 transcription factor which induces expression of STOMAGEN, a mesophyll-derived secreted peptide, that in turn leads to stabilization of a master regulator of stomatal development in the epidermis.

    • Shenqi Wang
    • , Zimin Zhou
    •  & On Sun Lau
  • Article
    | Open Access

    The tall wheat grass-derived stem rust resistance genes Sr26 and Sr61 are among a few ones that are effective to all current dominant races of stem rust, including Ug99. Here, the authors show that the two genes are present in a small non-recombinogenic segment but encode two unrelated NLR proteins.

    • Jianping Zhang
    • , Timothy C. Hewitt
    •  & Evans S. Lagudah
  • Article
    | Open Access

    Existing studies of the chromatin accessibility, the primary mark of regulatory DNA, in Arabidopsis are based mainly on bulk samples. Here, the authors report the regulatory landscape of Arabidopsis thaliana roots at single-cell resolution.

    • Michael W. Dorrity
    • , Cristina M. Alexandre
    •  & Josh T. Cuperus
  • Article
    | Open Access

    The ability to target DNA methylation to specific loci is important for both basic and applied research. Here, the authors fuse CG-specific methyltransferase SssI with an artificial zinc finger protein for DNA methylation targeting and show the chromatin features favorable for efficient gain of methylation.

    • Wanlu Liu
    • , Javier Gallego-Bartolomé
    •  & Steven E. Jacobsen
  • Article
    | Open Access

    AtEH/Pan1 proteins contain two N-terminal Eps15 homology (EH) domains and are subunits of the endocytic TPLATE complex present in plants. Here, the authors combine X-ray crystallography, NMR and MD simulations with biochemical and in planta analysis to characterize the two AtEH1/Pan1 EH domains and reveal their structural differences and complementary functional roles.

    • Klaas Yperman
    • , Anna C. Papageorgiou
    •  & Daniel Van Damme
  • Article
    | Open Access

    Structural insights into the small heat shock proteins (sHsps) complexes with their substrates are sparse. Here, cryo-EM structure of a plastid sHsp, Hsp21, in complex with a bona fide substrate 1-deoxy-D-xylulose 5-phosphate synthase (DXPS), suggests the anti-aggregation mechanism employed by sHsps.

    • Chuanyang Yu
    • , Stephen King Pong Leung
    •  & Wilson Chun Yu Lau
  • Article
    | Open Access

    Plants respond to warmth via growth processes termed thermomorphogenesis. Here, via a phosphoproteomics approach, the authors show that the mitogen activated protein kinase TOT3 regulates thermomorphogenesis in both wheat and Arabidopsis and modifies brassinosteroid signaling in Arabidopsis.

    • Lam Dai Vu
    • , Xiangyu Xu
    •  & Ive De Smet
  • Article
    | Open Access

    Pinoresinol–lariciresinol reductases (PLRs) are enzymes involved in the lignan biosynthesis. Here, crystal structures of three PLRs in the apo, substrate-bound and product-bound states, and accompanying mutagenesis provide insight into PLRs catalytic mechanism and suggest a strategy for PLR engineering.

    • Ying Xiao
    • , Kai Shao
    •  & Wansheng Chen
  • Article
    | Open Access

    Accumulating evidences point to a discrepancy in the epigenetic behaviour of transgenes and endogenous genes. Here, via characterization of mutants impaired in histone demethylases JMJ14 and IBM1, the authors show that transgenes and endogenous genes are regulated by different epigenetic mechanisms in Arabidopsis.

    • Nicolas Butel
    • , Agnès Yu
    •  & Hervé Vaucheret
  • Article
    | Open Access

    Geminiviruses cause substantial damage to crops worldwide. Here Wu et al. show that geminivirus replication relies upon the host DNA polymerases α and δ, which produce double-stranded DNA intermediates and new copies of the viral genome, respectively, and is modulated by the viral C3 protein.

    • Mengshi Wu
    • , Hua Wei
    •  & Rosa Lozano-Durán
  • Article
    | Open Access

    S-acylation is a reversible protein post-translational modification that often regulates protein function at the plasma membrane. Here the authors show that an Arabidopsis extracellular ATP receptor P2K1 mediates phosphorylation of two S-acyltransferases which in turn mediate S-acylation of P2K1 and dampen ATP responses.

    • Dongqin Chen
    • , Fengsheng Hao
    •  & Gary Stacey
  • Article
    | Open Access

    In contrast to common bean, tepary bean is highly adapted to heat and drought. Here, the authors assemble the genomes of tepary bean landrace and wild accession, discuss the possible mechanism for resilience to heat stress, and reveal a reduced disease resistance gene repertoire.

    • Samira Mafi Moghaddam
    • , Atena Oladzad
    •  & Phillip E. McClean
  • Article
    | Open Access

    T-DNA mutants have been widely used for Arabidopsis gene function characterization. Here, by characterizing a null mutant created by CRISPR, the authors show that previous reported function of H2A.W is confounded by a T-DNA insertion induced chromosomal rearrangement and reveal its role in regulating heterochromatin accessibility.

    • Pierre Bourguet
    • , Colette L. Picard
    •  & Olivier Mathieu
  • Article
    | Open Access

    The genomic organization and origin of the avenacin biosynthetic gene cluster remain unknown. Here, the authors assemble the genome of diploid oat Avena strigosa, reveal the structure and organization of the consecutive genes, characterize the last two missing pathway steps, and investigate the origin of the pathway in cereals.

    • Yan Li
    • , Aymeric Leveau
    •  & Anne Osbourn