bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization ofCYCLOPHILLIN38shows that a photosynthesis-derived systemic signal controls lateral root emergence
Authors: Duan Lina , Pérez-Ruiz Juan Manuel , Cejudo Francisco Javier , Dinneny José R 
Published: January 2021

AbstractPhotosynthesis in leaves generates fixed-carbon resources and essential metabolites that support sink tissues, such as roots. Two of these metabolites, sucrose and auxin, promote growth in root systems, but the explicit connection between photosynthetic activity and control of root architecture has not been explored. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the Arabidopsis thaliana CYCLOPHILIN 38 (CYP38) gene, which causes accumulation of pre-emergent stage lateral roots. CYP38 was previously reported to stabilize photosystem II (PSII) in chloroplasts. CYP38 expression is enriched in shoots, and grafting experiments show that the gene acts non-cell-autonomously to promote lateral root emergence. Growth of wild-type plants under low-light conditions phenocopies the cyp38 lateral root emergence defect, as does the inhibition of PSII-dependent electron transport or Nicotinamide adenine dinucleotide phosphate (NADPH) production. Importantly, these perturbations to photosynthetic activity rapidly suppress lateral root emergence, which is separate from their effects on shoot size. Supplementary exogenous sucrose largely rescued primary root (PR) growth in cyp38, but not lateral root growth. Auxin (indole-3-acetic acid (IAA)) biosynthesis from tryptophan is dependent on reductant generated during photosynthesis. Consistently, we found that wild-type seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. IAA treatment rescued the cyp38 lateral root defect, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. These data directly confirm the importance of CYP38-dependent photosynthetic activity in supporting root growth, and define the specific contributions of two metabolites in refining root architecture under light-limited conditions.
Multi-omics approach reveals the contribution of KLU to leaf longevity and drought tolerance
Authors: Jiang Liang , Yoshida Takuya , Stiegert Sofia , Jing Yue , Alseekh Saleh , Lenhard Michael , Pérez-Alfocea Francisco , Fernie Alisdair R 
Published: January 2021

Abstract
KLU, encoded by a cytochrome P450 CYP78A family gene, generates an important—albeit unknown—mobile signal that is distinct from the classical phytohormones. Multiple lines of evidence suggest that KLU/KLU-dependent signaling functions in several vital developmental programs, including leaf initiation, leaf/floral organ growth, and megasporocyte cell fate. However, the interactions between KLU/KLU-dependent signaling and the other classical phytohormones, as well as how KLU influences plant physiological responses, remain poorly understood. Here, we applied in-depth, multi-omics analysis to monitor transcriptome and metabolome dynamics in klu-mutant and KLU-overexpressing Arabidopsis plants. By integrating transcriptome sequencing data and primary metabolite profiling alongside phytohormone measurements, our results showed that cytokinin signaling, with its well-established function in delaying leaf senescence, was activated in KLU-overexpressing plants. Consistently, KLU-overexpressing plants exhibited significantly delayed leaf senescence and increased leaf longevity, whereas the klu-mutant plants showed early leaf senescence. In addition, proline biosynthesis and catabolism were enhanced following KLU overexpression owing to increased expression of genes associated with proline metabolism. Furthermore, KLU-overexpressing plants showed enhanced drought-stress tolerance and reduced water loss. Collectively, our work illustrates a role for KLU in positively regulating leaf longevity and drought tolerance by synergistically activating cytokinin signaling and promoting proline metabolism. These data promote KLU as a potential ideal genetic target to improve plant fitness.
VAP-RELATED SUPPRESSORS OF TOO MANY MOUTHS (VST) family proteins are regulators of root system architecture
Authors: Shao Yanlin , Lehner Kevin R , Zhou Hongzhu , Taylor Isaiah , Zhu Mingyuan , Mao Chuanzao , Benfey Philip N 
Published: January 2021

Abstract
Root system architecture (RSA) is a key factor in the efficiency of nutrient capture and water uptake in plants. Understanding the genetic control of RSA will be useful in minimizing fertilizer and water usage in agricultural cropping systems. Using a hydroponic screen and a gel-based imaging system, we identified a rice (Oryza sativa) gene, VAP-RELATED SUPPRESSOR OF TOO MANY MOUTHS1 (OsVST1), which plays a key role in controlling RSA. This gene encodes a homolog of the VAP-RELATED SUPPRESSORS OF TOO MANY MOUTHS (VST) proteins in Arabidopsis (Arabidopsis thaliana), which promote signaling in stomata by mediating plasma membrane–endoplasmic reticulum contacts. OsVST1 mutants have shorter primary roots, decreased root meristem size, and a more compact RSA. We show that the Arabidopsis VST triple mutants have similar phenotypes, with reduced primary root growth and smaller root meristems. Expression of OsVST1 largely complements the short root length and reduced plant height in the Arabidopsis triple mutant, supporting conservation of function between rice and Arabidopsis VST proteins. In a field trial, mutations in OsVST1 did not adversely affect grain yield, suggesting that modulation of this gene could be used as a way to optimize RSA without an inherent yield penalty.
DEEP GREEN PANICLE1 suppresses GOLDEN2-LIKE activity to reduce chlorophyll synthesis in rice glumes
Authors: Zhang Chao , Zhang Jianxiang , Tang Yujie , Liu Kangwei , Liu Yan , Tang Jiaqi , Zhang Tao , Yu Hengxiu 
Published: January 2021

AbstractUnderstanding the regulation mechanisms of photosynthesis is key to improving its efficiency and, ultimately, crop yield. In this study, we report that DEEP GREEN PANICLE1 (DGP1) is involved in photosynthesis regulation in rice (Oryza sativa L.). We identified the dgp1 mutant, which has increased chlorophyll content in glumes. The mutated gene was isolated by map-based cloning. Knockout plants, generated using a gene editing approach, mimic the phenotype of dgp1. Overexpression of DGP1 leads to chlorotic leaves and glumes. DGP1 is a plant-specific protein with a conserved TIGR01589 domain. The expression of DGP1 was detected in green tissues and is induced by light. Moreover, genes involved in key steps of chlorophyll synthesis are upregulated in the glumes of dgp1. Importantly, we found that DGP1 interacts with the rice proteins GOLDEN2-LIKE1 (OsGLK1) and GOLDEN2-LIKE2 (OsGLK2), the two transcription factors involved in the regulation of photosynthesis. Transactivation assays showed that DGP1 represses the activation activity of OsGLK1 on its target genes. Our results demonstrate that DGP1 is a repressor of OsGLK activity and thus photosynthesis in rice. Manipulation of this gene and its homologs in other crops may provide new approaches for high photosynthetic efficiency breeding.
The nucellus: between cell elimination and sugar transport
Authors: Lu Jing , Le Hir Rozenn , Gómez-Páez Dennys-Marcela , Coen Olivier , Péchoux Christine , Jasinski Sophie , Magnani Enrico 
Published: January 2021

Abstract
The architecture of the seed is shaped by the processes of tissue partitioning, which determines the volume ratio of maternal and zygotic tissues, and nutrient partitioning, which regulates nutrient distribution among tissues. In angiosperms, early seed development is characterized by antagonistic development of the nucellus maternal tissue and the endosperm fertilization product to become the main sugar sink. This process marked the evolution of angiosperms and outlines the most ancient seed architectures. In Arabidopsis, the endosperm partially eliminates the nucellus and imports sugars from the seed coat. Here, we show that the nucellus is symplasmically connected to the chalaza, the seed nutrient unloading zone, and works as both a sugar sink and source alongside the seed coat. After fertilization, the transient nucellus accumulates starch early on and releases it in the apoplasmic space during its elimination. By contrast, the persistent nucellus exports sugars toward the endosperm through the SWEET4 hexose facilitator. Finally, we analyzed sugar metabolism and transport in the transparent testa 16 mutant, which fails to undergo nucellus cell elimination, which shed light on the coordination between tissue and nutrient partitioning. Overall, this study identifies a path of sugar transport in the Arabidopsis seed and describes a link between sugar redistribution and the nucellus cell-elimination program.
Molecular basis for high ligand sensitivity and selectivity of strigolactone receptors in Striga
Authors: Wang Yupei , Yao Ruifeng , Du Xiaoxi , Guo Lvjun , Chen Li , Xie Daoxin , Smith Steven M 
Published: January 2021

Abstract
Seeds of the root parasitic plant Striga hermonthica can sense very low concentrations of strigolactones (SLs) exuded from host roots. The S. hermonthica hyposensitive to light (ShHTL) proteins are putative SL receptors, among which ShHTL7 reportedly confers sensitivity to picomolar levels of SL when expressed in Arabidopsis thaliana. However, the molecular mechanism underlying ShHTL7 sensitivity is unknown. Here we determined the ShHTL7 crystal structure and quantified its interactions with various SLs and key interacting proteins. We established that ShHTL7 has an active-site pocket with broad-spectrum response to different SLs and moderate affinity. However, in contrast to other ShHTLs, we observed particularly high affinity of ShHTL7 for F-box protein AtMAX2. Furthermore, ShHTL7 interacted with AtMAX2 and with transcriptional regulator AtSMAX1 in response to nanomolar SL concentration. ShHTL7 mutagenesis analyses identified surface residues that contribute to its high-affinity binding to AtMAX2 and residues in the ligand binding pocket that confer broad-spectrum response to SLs with various structures. Crucially, yeast-three hybrid experiments showed that AtMAX2 confers responsiveness of the ShHTL7–AtSMAX1 interaction to picomolar levels of SL in line with the previously reported physiological sensitivity. These findings highlight the key role of SL-induced MAX2–ShHTL7–SMAX1 complex formation in determining the sensitivity to SL. Moreover, these data suggest a strategy to screen for compounds that could promote suicidal seed germination at physiologically relevant levels.
A temperature-sensitive FERONIA mutant allele that alters root hair growth
Authors: Kim Daewon , Yang Jiyuan , Gu Fangwei , Park Sungjin , Combs Jonathon , Adams Alexander , Mayes Heather B , Jeon Su Jeong , Bahk Jeong Dong , Nielsen Erik 
Published: January 2021

Abstract
In plants, root hairs undergo a highly polarized form of cell expansion called tip-growth, in which cell wall deposition is restricted to the root hair apex. In order to identify essential cellular components that might have been missed in earlier genetic screens, we identified conditional temperature-sensitive (ts) root hair mutants by ethyl methanesulfonate mutagenesis in Arabidopsis thaliana. Here, we describe one of these mutants, feronia-temperature sensitive (fer-ts). Mutant fer-ts seedlings were unaffected at normal temperatures (20°C), but failed to form root hairs at elevated temperatures (30°C). Map based-cloning and whole-genome sequencing revealed that fer-ts resulted from a G41S substitution in the extracellular domain of FERONIA (FER). A functional fluorescent fusion of FER containing the fer-ts mutation localized to plasma membranes, but was subject to enhanced protein turnover at elevated temperatures. While tip-growth was rapidly inhibited by addition of rapid alkalinization factor 1 (RALF1) peptides in both wild-type and fer-ts mutants at normal temperatures, root elongation of fer-ts seedlings was resistant to added RALF1 peptide at elevated temperatures. Additionally, at elevated temperatures fer-ts seedlings displayed altered reactive oxygen species (ROS) accumulation upon auxin treatment and phenocopied constitutive fer mutant responses to a variety of plant hormone treatments. Molecular modeling and sequence comparison with other Catharanthus roseus receptor-like kinase 1L (CrRLK1L) receptor family members revealed that the mutated glycine in fer-ts is highly conserved, but is not located within the recently characterized RALF23 and LORELI-LIKE-GLYCOPROTEIN 2 binding domains, perhaps suggesting that fer-ts phenotypes may not be directly due to loss of binding to RALF1 peptides.
Hyperoside regulates its own biosynthesis via MYB30 in promoting reproductive development and seed set in okra
Authors: Yang Qing , Song Zhihua , Dong Biying , Niu Lili , Cao Hongyan , Li Hanghang , Du Tingting , Liu Tengyue , Yang Wanlong , Meng Dong , Fu Yujie 
Published: January 2021

Abstract
Flavonoids are secondary metabolites that play important roles in fruit and vegetable development. Here, we examined the function of hyperoside, a unique flavonoid in okra (Abelmoschus esculentus), known to promote both flowering and seed set. We showed that the exogenous application of hyperoside significantly improved pollen germination rate and pollen tube growth by almost 50%, resulting in a 42.7% increase in the seed set rate. Of several genes induced by the hyperoside treatment, AeUF3GaT1, which encodes an enzyme that catalyzes the last step of hyperoside biosynthesis, was the most strongly induced. The transcription factor AeMYB30 enhanced AeUFG3aT1 transcription by directly binding to the AeUFG3aT1 promoter. We studied the effect of the hyperoside application on the expression of 10 representative genes at four stages of reproductive development, from pollination to seed maturity. We firstly developed an efficient transformation system that uses seeds as explants to study the roles of AeMYB30 and AeUFG3aT1. Overexpression of AeMYB30 or AeUF3GaT1 promoted seed development. Moreover, exogenous application of hyperoside partially restored the aberrant phenotype of AeUF3GaT1 RNA-interference plants. Thus, hyperoside promotes seed set in okra via a pathway involving AeUF3GaT and AeMYB30, and the exogenous application of this flavonoid is a simple method that can be used to improve seed quality and yield in okra.
The bright side of parasitic plants: what are they good for?
Authors: Těšitel Jakub , Li Ai-Rong , Knotková Kateřina , McLellan Richard , Bandaranayake Pradeepa C G , Watson David M 
Published: January 2021

Abstract
Parasitic plants are mostly viewed as pests. This is caused by several species causing serious damage to agriculture and forestry. There is however much more to parasitic plants than presumed weeds. Many parasitic plans exert even positive effects on natural ecosystems and human society, which we review in this paper. Plant parasitism generally reduces the growth and fitness of the hosts. The network created by a parasitic plant attached to multiple host plant individuals may however trigger transferring systemic signals among these. Parasitic plants have repeatedly been documented to play the role of keystone species in the ecosystems. Harmful effects on community dominants, including invasive species, may facilitate species coexistence and thus increase biodiversity. Many parasitic plants enhance nutrient cycling and provide resources to other organisms like herbivores or pollinators, which contributes to facilitation cascades in the ecosystems. There is also a long tradition of human use of parasitic plants for medicinal and cultural purposes worldwide. Few species provide edible fruits. Several parasitic plants are even cultivated by agriculture/forestry for efficient harvesting of their products. Horticultural use of some parasitic plant species has also been considered. While providing multiple benefits, parasitic plants should always be used with care. In particular, parasitic plant species should not be cultivated outside their native geographical range to avoid the risk of their uncontrolled spread and the resulting damage to ecosystems.
Transport of UDP-rhamnose by URGT2, URGT4, and URGT6 modulates rhamnogalacturonan-I length
Authors: Saez-Aguayo Susana , Parra-Rojas Juan Pablo , Sepúlveda-Orellana Pablo , Celiz-Balboa Jonathan , Arenas-Morales Verónica , Sallé Christine , Salinas-Grenet Hernán , Largo-Gosens Asier , North Helen M , Ralet Marie-Christine , Orellana Ariel 
Published: January 2021

Abstract
Rhamnogalacturonan-I biosynthesis occurs in the lumen of the Golgi apparatus, a compartment where UDP-Rhamnose and UDP-Galacturonic Acid are the main substrates for synthesis of the backbone polymer of pectin. Recent studies showed that UDP-Rha is transported from the cytosol into the Golgi apparatus by a family of six UDP-rhamnose/UDP-galactose transporters (URGT1-6). In this study, analysis of adherent and soluble mucilage (SM) of Arabidopsis thaliana seeds revealed distinct roles of URGT2, URGT4, and URGT6 in mucilage biosynthesis. Characterization of SM polymer size showed shorter chains in the urgt2 urgt4 and urgt2 urgt4 urgt6 mutants, suggesting that URGT2 and URGT4 are mainly involved in Rhamnogalacturonan-I (RG-I) elongation. Meanwhile, mutants in urgt6 exhibited changes only in adherent mucilage (AM). Surprisingly, the estimated number of RG-I polymer chains present in urgt2 urgt4 and urgt2 urgt4 urgt6 mutants was higher than in wild-type. Interestingly, the increased number of shorter RG-I chains was accompanied by an increased amount of xylan. In the urgt mutants, expression analysis of other genes involved in mucilage biosynthesis showed some compensation. Studies of mutants of transcription factors regulating mucilage formation indicated that URGT2, URGT4, and URGT6 are likely part of a gene network controlled by these regulators and involved in RG-I synthesis. These results suggest that URGT2, URGT4, and URGT6 play different roles in the biosynthesis of mucilage, and the lack of all three affects the production of shorter RG-I polymers and longer xylan domains.
Alternative splicing creates a pseudo-strictosidine β-d-glucosidase modulating alkaloid synthesis in Catharanthus roseus
Authors: Carqueijeiro Inês , Koudounas Konstantinos , Dugé de Bernonville Thomas , Sepúlveda Liuda Johana , Mosquera Angela , Bomzan Dikki Pedenla , Oudin Audrey , Lanoue Arnaud , Besseau Sébastien , Lemos Cruz Pamela , Kulagina Natalja , Stander Emily A , Eymieux Sébastien , Burlaud-Gaillard Julien , Blanchard Emmanuelle , Clastre Marc , Atehortùa Lucia , St-Pierre Benoit , Giglioli-Guivarc’h Nathalie , Papon Nicolas , Nagegowda Dinesh A , O’Connor Sarah E , Courdavault Vincent 
Published: January 2021

Abstract
Deglycosylation is a key step in the activation of specialized metabolites involved in plant defense mechanisms. This reaction is notably catalyzed by β-glucosidases of the glycosyl hydrolase 1 (GH1) family such as strictosidine β-d-glucosidase (SGD) from Catharanthus roseus. SGD catalyzes the deglycosylation of strictosidine, forming a highly reactive aglycone involved in the synthesis of cytotoxic monoterpene indole alkaloids (MIAs) and in the crosslinking of aggressor proteins. By exploring C. roseus transcriptomic resources, we identified an alternative splicing event of the SGD gene leading to the formation of a shorter isoform of this enzyme (shSGD) that lacks the last 71-residues and whose transcript ratio with SGD ranges from 1.7% up to 42.8%, depending on organs and conditions. Whereas it completely lacks β-glucosidase activity, shSGD interacts with SGD and causes the disruption of SGD multimers. Such disorganization drastically inhibits SGD activity and impacts downstream MIA synthesis. In addition, shSGD disrupts the metabolic channeling of downstream biosynthetic steps by hampering the recruitment of tetrahydroalstonine synthase in cell nuclei. shSGD thus corresponds to a pseudo-enzyme acting as a regulator of MIA biosynthesis. These data shed light on a peculiar control mechanism of β-glucosidase multimerization, an organization common to many defensive GH1 members.
A multiple ion-uptake phenotyping platform reveals shared mechanisms affecting nutrient uptake by roots
Authors: Griffiths Marcus , Roy Sonali , Guo Haichao , Seethepalli Anand , Huhman David , Ge Yaxin , Sharp Robert E , Fritschi Felix B , York Larry M 
Published: January 2021

Abstract
Nutrient uptake is critical for crop growth and is determined by root foraging in soil. Growth and branching of roots lead to effective root placement to acquire nutrients, but relatively little is known about absorption of nutrients at the root surface from the soil solution. This knowledge gap could be alleviated by understanding sources of genetic variation for short-term nutrient uptake on a root length basis. A modular platform called RhizoFlux was developed for high-throughput phenotyping of multiple ion-uptake rates in maize (Zea mays L.). Using this system, uptake rates were characterized for the crop macronutrients nitrate, ammonium, potassium, phosphate, and sulfate among the Nested Association Mapping (NAM) population founder lines. The data revealed substantial genetic variation for multiple ion-uptake rates in maize. Interestingly, specific nutrient uptake rates (nutrient uptake rate per length of root) were found to be both heritable and distinct from total uptake and plant size. The specific uptake rates of each nutrient were positively correlated with one another and with specific root respiration (root respiration rate per length of root), indicating that uptake is governed by shared mechanisms. We selected maize lines with high and low specific uptake rates and performed an RNA-seq analysis, which identified key regulatory components involved in nutrient uptake. The high-throughput multiple ion-uptake kinetics pipeline will help further our understanding of nutrient uptake, parameterize holistic plant models, and identify breeding targets for crops with more efficient nutrient acquisition.
The nucleolar protein SAHY1 is involved in pre-rRNA processing and normal plant growth
Authors: Hsu Pei-jung , Tan Mei-Chen , Shen Hwei-Ling , Chen Ya-Huei , Wang Ya-Ying , Hwang San-Gwang , Chiang Ming-Hau , Le Quang-Vuong , Kuo Wen-Shuo , Chou Ying-Chan , Lin Shih-Yun , Jauh Guang-Yuh , Cheng Wan-Hsing 
Published: January 2021

AbstractAlthough the nucleolus is involved in ribosome biogenesis, the functions of numerous nucleolus-localized proteins remain unclear. In this study, we genetically isolated Arabidopsis thaliana salt hypersensitive mutant 1 (sahy1), which exhibits slow growth, short roots, pointed leaves, and sterility. SAHY1 encodes an uncharacterized protein that is predominantly expressed in root tips, early developing seeds, and mature pollen grains and is mainly restricted to the nucleolus. Dysfunction of SAHY1 primarily causes the accumulation of 32S, 18S-A3, and 27SB pre-rRNA intermediates. Coimmunoprecipitation experiments further revealed the interaction of SAHY1 with ribosome proteins and ribosome biogenesis factors. Moreover, sahy1 mutants are less sensitive to protein translation inhibitors and show altered expression of structural constituents of ribosomal genes and ribosome subunit profiles, reflecting the involvement of SAHY1 in ribosome composition and ribosome biogenesis. Analyses of ploidy, S-phase cell cycle progression, and auxin transport and signaling indicated the impairment of mitotic activity, translation of auxin transport carrier proteins, and expression of the auxin-responsive marker DR5::GFP in the root tips or embryos of sahy1 plants. Collectively, these data demonstrate that SAHY1, a nucleolar protein involved in ribosome biogenesis, plays critical roles in normal plant growth in association with auxin transport and signaling.