A Novel mechanism of herbicide action through disruption of pyrimidine biosynthesis.

A lead aryl pyrrolidinone anilide identified using high-throughput in vivo screening was optimized for efficacy, crop safety, and weed spectrum, resulting in tetflupyrolimet. Known modes of action were ruled out through in vitro enzyme and in vivo plant-based assays. Genomic sequencing of aryl pyrrolidinone anilide-resistant Arabidopsis thaliana progeny combined with nutrient reversal experiments and metabolomic analyses confirmed that the molecular target of the chemistry was dihydroorotate dehydrogenase (DHODH), the enzyme that catalyzes the fourth step in the de novo pyrimidine biosynthesis pathway. In vitro enzymatic and biophysical assays and a cocrystal structure with purified recombinant plant DHODH further confirmed this enzyme as the target site of this class of chemistry. Like known inhibitors of other DHODH orthologs, these molecules occupy the membrane-adjacent binding site of the electron acceptor ubiquinone. Identification of a new herbicidal chemical scaffold paired with a novel mode of action, the first such finding in over three decades, represents an important leap in combatting weed resistance and feeding a growing worldwide population.

Radiosurgical considerations for cavernous sinus hemangioma: long-term clinical outcomes.

BACKGROUND: Cavernous hemangiomas are rare vascular tumors in the cavernous sinus. Cranial neuropathies induced by cavernous sinus hemangiomas (CSH) necessitate tumor reduction, but surgery is extremely difficult due to the abundant vascularization of the lesion. We studied the effectiveness and safety of Gamma Knife radiosurgery (GKRS) for CSH. METHODS: We performed a retrospective analysis of 25 patients with CSH who were treated by GKRS between March 1992 and December 2014. Age, sex, target volume, and irradiation dose were analyzed as prognostic factors for CSH treated by GKRS. RESULTS: Eleven (84.6 %) patients had tumor shrinkage within 12 months after GKRS. Two patients experienced tumor progression, but tumor size decreased over 2 years after GKRS. No patients had permanent complications, and all patients experienced symptomatic improvement. There were no significant factors that predicted the prognosis of CSH. CONCLUSIONS: The optimal treatment for CSH has been unclear; however, in this study, GKRS was an effective and safe treatment for CSH. Thus, GKRS may be a primary treatment for CSHs in high-risk surgery patients.

Polypyrimidine tract-binding proteins of potato mediate tuberization through an interaction with StBEL5 RNA.

Polypyrimidine tract-binding (PTB) proteins are a family of RNA-binding proteins that function in a wide range of RNA metabolic processes by binding to motifs rich in uracils and cytosines. A PTB protein of pumpkin was identified as the core protein of an RNA-protein complex that trafficks RNA. The biological function of the PTB-RNA complex, however, has not been demonstrated. In potato, six PTB proteins have been identified, and two, designated StPTB1 and StPTB6, are similar to the phloem-mobile pumpkin type. RNA binding assays confirmed the interaction of StPTB1 and StPTB6 with discrete pyrimidine-rich sequences of the 3'-untranslated regions of the phloem-mobile mRNA, StBEL5. The promoter of StPTB1 was active in companion cells of phloem in both stem and petioles. Expression of both types was evident in phloem cells of roots and in stolons during tuber formation. RNA accumulation of both PTB proteins was induced by short days in leaves in correlation with enhanced accumulation of StBEL5 RNA. StPTB suppression lines exhibited reduced tuber yields and decreased StBEL5 RNA accumulation, whereas StPTB overexpression lines displayed an increase in tuber production correlated with the enhanced production in stolons of steady-state levels of StBEL5 transcripts and RNA of key tuber identity genes. In StPTB overexpression lines, both the stability and long-distance transport of StBEL5 transcripts were enhanced, whereas in suppression lines stability and transport decreased. Using a transgenic approach, it is shown that the StPTB family of RNA-binding proteins regulate specific stages of development through an interaction with phloem-mobile transcripts of StBEL5.

The mRNA of a Knotted1-like transcription factor of potato is phloem mobile.

Potato Homeobox1 (POTH1) is a Knotted1-like transcription factor from the Three Amino Acid Loop Extension (TALE) superfamily that is involved in numerous aspects of development in potato (Solanum tuberosum L). POTH1 interacts with its protein partner, StBEL5, to facilitate binding to specific target genes to modulate hormone levels, mediate leaf architecture, and enhance tuber formation. In this study, promoter analyses show that the upstream sequence of POTH1 drives ß-glucuronidase activity in response to light and in association with phloem cells in both petioles and stems. Because POTH1 transcripts have previously been detected in phloem cells, long-distance movement of its mRNA was tested. Using RT-PCR and transgenic potato lines over-expressing POTH1, in vitro micrografts demonstrated unilateral movement of POTH1 RNA in a rootward direction. Movement across a graft union into leaves from newly arising axillary shoots and roots of wild type stocks was verified using soil-grown tobacco heterografts. Leaves from the wild type stock containing the mobile POTH1 RNA exhibited a reduction in leaf size relative to leaves from wild type grafts. Both untranslated regions of POTH1 when fused to an expression marker ß-glucuronidase, repressed its translation in tobacco protoplasts. RNA/protein binding assays demonstrated that the UTRs of POTH1 bind to two RNA-binding proteins, a polypyrimidine tract-binding protein and an alba-domain type. Conserved glycerol-responsive elements (GRE), specific to alba-domain interaction, are duplicated in both the 5' and 3' untranslated regions of POTH1. These results suggest that POTH1 functions as a mobile signal in regulating development.

An outlook of FMC's current and future herbicide-resistance management strategies.

Herbicide resistance has emerged globally as a serious threat to profitable crop production. FMC promotes integrated weed management approaches including responsible use of existing herbicides, use of non-herbicide weed control tools, awareness about herbicide resistance issues, and support to herbicide resistance management initiatives. FMC is dedicated to developing sustainable weed control solutions through the discovery of new herbicides with novel sites-of-action, effective formulations, advanced application technology, and proactive monitoring for herbicide resistance. © 2020 Society of Chemical Industry.

Identification of transcription-factor genes expressed in the Arabidopsis female gametophyte.

BACKGROUND: In flowering plants, the female gametophyte is typically a seven-celled structure with four cell types: the egg cell, the central cell, the synergid cells, and the antipodal cells. These cells perform essential functions required for double fertilization and early seed development. Differentiation of these distinct cell types likely involves coordinated changes in gene expression regulated by transcription factors. Therefore, understanding female gametophyte cell differentiation and function will require dissection of the gene regulatory networks operating in each of the cell types. These efforts have been hampered because few transcription factor genes expressed in the female gametophyte have been identified. To identify such genes, we undertook a large-scale differential expression screen followed by promoter-fusion analysis to detect transcription-factor genes transcribed in the Arabidopsis female gametophyte. RESULTS: Using quantitative reverse-transcriptase PCR, we analyzed 1,482 Arabidopsis transcription-factor genes and identified 26 genes exhibiting reduced mRNA levels in determinate infertile 1 mutant ovaries, which lack female gametophytes, relative to ovaries containing female gametophytes. Spatial patterns of gene transcription within the mature female gametophyte were identified for 17 transcription-factor genes using promoter-fusion analysis. Of these, ten genes were predominantly expressed in a single cell type of the female gametophyte including the egg cell, central cell and the antipodal cells whereas the remaining seven genes were expressed in two or more cell types. After fertilization, 12 genes were transcriptionally active in the developing embryo and/or endosperm. CONCLUSIONS: We have shown that our quantitative reverse-transcriptase PCR differential-expression screen is sufficiently sensitive to detect transcription-factor genes transcribed in the female gametophyte. Most of the genes identified in this study have not been reported previously as being expressed in the female gametophyte. Therefore, they might represent novel regulators and provide entry points for reverse genetic and molecular approaches to uncover the gene regulatory networks underlying female gametophyte development.

Thermal and electrical properties of nanocomposites based on acrylic copolymers and multiwalled carbon nanotube.

Nanocomposites based on multiwalled carbon nanotubes (MWCNT) and various acrylic copolymers, poly(methyl methacrylate-co-butyl acrylate) (PMBA) and poly(methyl methacrylate-co-butyl acrylate-co-acrylic acid) (PMAA), were prepared and the effects of the copolymer composition on the thermal and electrical properties of the nanocomposites were investigated. The results showed that there was a decrease in the glass transition temperature (T(g)) with increasing MWCNT content in the nanocomposites based on the acrylic copolymers. This decrease in T(g) was attributed to the characteristics of the nanocomposites in which the compatibility between the matrix polymers and MWCNT were relatively poor and there was an increase in free volume at the interface. It was found that the critical concentrations, P(c)s, for the percolation of MWCNTs in terms of the electrical resistivity decreased with increasing acrylic acid content in the matrix polymers. In addition, the thermal conductivity of the nanocomposites increased with increasing MWCNT content if there was good compatibility between the matrix polymer and MWCNT while those of the nanocomposites with relatively poor compatibility between the matrix and MWCNT showed little change.

Biportal Endoscopic Spine Surgery for Various Foraminal Lesions at the Lumbosacral Lesion.

The stenosing foramen of L5-S1 by several degenerative diseases is one of the challenging areas on surgical approaching because of the deeper depth and steep slope in the lumbosacral junction. The floating view using unilateral biportal endoscopic spine surgery rather than docking into the Kambin's zone can make the foraminal structures seen panoramically and permit dynamic handling of various instruments without destroying the facet joint and causing iatrogenic instability. Fine discrimination of structural margins in helps of the higher magnification and gentle manipulation of neural structures just as in open spine surgery could be guaranteed using floating technique from the target structures. Selective decompression with preserving innocent structures including facet joints could relieve foraminal lesions at the L5-S1 and decrease the necessity of fusion surgery caused by wider decompression and iatrogenic instability.

Revascularization as Treatment of a Ruptured Fusiform Aneurysm at the Cortical Segment of the Superior Cerebellar Artery: A Case Report and Literature Review.

A fusiform aneurysm of the superior cerebellar artery (SCA) is rare and mainly occurs at the proximal segment. A 71-year-old female patient was admitted to our institution with a subarachnoid hemorrhage. Angiography revealed dominance of both SCAs with aplasia of both the posterior inferior cerebellar artery and a fusiform aneurysm at the cortical segment of the left SCA involving the bifurcation site. Bypass connecting the left occipital artery to the inferior branch of the left SCA was performed, followed by trapping and clipping of the proximal and distal parts of the aneurysm, respectively. Blood flow was maintained in a retrograde manner from the inferior branch to the superior branch. She was discharged with no neurologic deficits and continues to be followed up by our department as an outpatient. This is the first report of a treatment method for a fusiform aneurysm located in the cortical segment of the SCA.

A Clinical Analysis of Secondary Surgery in Trigeminal Neuralgia Patients Who Failed Prior Treatment.

OBJECTIVE: Although many treatment modalities have been introduced for trigeminal neuralgia (TN), the long-term clinical results remain unsatisfactory. It has been particularly challenging to determine an appropriate treatment strategy for patients who have responded poorly to initial therapies. We analyzed the surgical outcomes in TN patients who failed prior treatments. METHODS: We performed a retrospective analysis of 37 patients with recurrent or persistent TN symptoms who underwent surgery at our hospital between January 2010 and December 2014. Patients with follow-up data of at least one year were included. The prior treatment modalities of the 37 patients included microvascular decompression (MVD), gamma knife radiosurgery (GKRS), and percutaneous procedures such as radiofrequency rhizotomy (RFR), balloon compression, and glycerol rhizotomy (GR). The mean follow-up period was 69.9 months (range : 16-173). The mean interval between the prior treatment and second surgery was 26 months (range : 7-123). We evaluated the surgical outcomes using the Barrow Neurological Institute (BNI) pain intensity scale. RESULTS: Among the 37 recurrent or persistent TN patients, 22 underwent MVD with partial sensory rhizotomy (PSR), 8 received MVD alone, and 7 had PSR alone. Monitoring of the surgical treatment outcomes via the BNI pain intensity scale revealed 8 (21.6%) patients with a score of I, 13 (35.1%) scoring II, 13 (35.1%) scoring III, and 3 (8.2%) scoring IV at the end of the follow-up period. Overall, 91.8% of patients had good surgical outcomes. With regard to postoperative complications, 1 patient had transient cerebrospinal fluid rhinorrhea (2.7%), another had a subdural hematoma (2.7%), and facial sensory changes were noted in 8 (21.1%) patients after surgery. CONCLUSION: Surgical interventions, such as MVD and PSR, are safe and very effective treatment modalities in TN patients who failed initial or prior treatments. We presume that the combination of MVD with PSR enabled us to obtain good short- and long-term surgical outcomes. Therefore, aggressive surgical treatment should be considered in patients with recurrent TN despite failure of various treatment modalities.

Using the Yeast Three-Hybrid System to Identify Proteins that Interact with a Phloem-Mobile mRNA.

Heterografting and RNA transport experiments have demonstrated the long-distance mobility of StBEL5 RNA, its role in controlling tuber formation, and the function of the 503-nt 3' untranslated region (UTR) of the RNA in mediating transport. Because the 3' UTR of StBEL5 is a key element in regulating several aspects of RNA metabolism, a potato leaf cDNA library was screened using the 3' UTR of StBEL5 as bait in the yeast three-hybrid (Y3H) system to identify putative partner RNA-binding proteins (RBPs). From this screen, 116 positive cDNA clones were isolated based on nutrient selection, HIS3 activation, and lacZ induction and were sequenced and classified. Thirty-five proteins that were predicted to function in either RNA- or DNA-binding were selected from this pool. Seven were monitored for their expression profiles and further evaluated for their capacity to bind to the 3' UTR of StBEL5 using ß-galactosidase assays in the Y3H system and RNA gel-shift assays. Among the final selections were two RBPs, a zinc finger protein, and one protein, StLSH10, from a family involved in light signaling. In this study, the Y3H system is presented as a valuable tool to screen and verify interactions between target RNAs and putative RBPs. These results can shed light on the dynamics and composition of plant RNA-protein complexes that function to regulate RNA metabolism.

The AGL62 MADS domain protein regulates cellularization during endosperm development in Arabidopsis.

Endosperm, a storage tissue in the angiosperm seed, provides nutrients to the embryo during seed development and/or to the developing seedling during germination. A major event in endosperm development is the transition between the syncytial phase, during which the endosperm nuclei undergo many rounds of mitosis without cytokinesis, and the cellularized phase, during which cell walls form around the endosperm nuclei. The molecular processes controlling this phase transition are not understood. In agl62 seeds, the endosperm cellularizes prematurely, indicating that AGL62 is required for suppression of cellularization during the syncytial phase. AGL62 encodes a Type I MADS domain protein that likely functions as a transcription factor. During seed development, AGL62 is expressed exclusively in the endosperm. During wild-type endosperm development, AGL62 expression is strong during the syncytial phase and then declines abruptly just before cellularization. By contrast, in mutant seeds containing defects in some FERTILIZATION-INDEPENDENT SEED (FIS) class Polycomb group genes, the endosperm fails to cellularize and AGL62 expression fails to decline. Together, these data suggest that AGL62 suppresses cellularization during the syncytial phase of endosperm development and that endosperm cellularization is triggered via direct or indirect AGL62 inactivation by the FIS polycomb complex.

AGL61 interacts with AGL80 and is required for central cell development in Arabidopsis.

The central cell of the female gametophyte plays a role in pollen tube guidance and in regulating the initiation of endosperm development. Following fertilization, the central cell gives rise to the seed's endosperm, which nourishes the developing embryo within the seed. The molecular mechanisms controlling specification and differentiation of the central cell are poorly understood. We identified AGL61 in a screen for transcription factor genes expressed in the female gametophyte. AGL61 encodes a Type I MADS domain protein, which likely functions as a transcription factor. Consistent with this, an AGL61-green fluorescent protein fusion protein is localized to the nucleus. In the context of the ovule and seed, AGL61 is expressed exclusively in the central cell and early endosperm. agl61 female gametophytes are affected in the central cell specifically. The morphological defects include an overall reduction in size of the central cell and a reduced or absent central cell vacuole. When fertilized with wild-type pollen, agl61 central cells fail to give rise to endosperm. In addition, synergid- and antipodal-expressed genes are ectopically expressed in agl61 central cells. The expression pattern and mutant phenotype of AGL61 are similar to those of AGL80, suggesting that AGL61 may function as a heterodimer with AGL80 within the central cell; consistent with this, AGL61 and AGL80 interact in yeast two-hybrid assays. Together, these data suggest that AGL61 functions as a transcription factor and controls the expression of downstream genes during central cell development.

Temporal and spatial expression of the major allergens in developing and germinating peanut seed.

Peanut (Arachis hypogaea) seed proteins Ara h 1, Ara h 2, and Ara h 3 are considered to be the major peanut allergens. However, little is known about their temporal and spatial expression during seed development and upon germination and seedling growth. In this study, transcript levels of the three major peanut allergen genes, ara h 1, ara h 2, and ara h 3, and their corresponding proteins were found in all cultivars. Expression patterns were heterogeneous depending on the specific peanut allergen gene and the cultivars tested. However, ara h 3 expression patterns among the cultivars were more variable than ara h 1 and ara h 2. Transcripts were tissue specific, observed in seeds, but not in leaves, flowers, or roots, and were undetectable during seed germination. In situ hybridizations and immunotissue prints revealed that both embryonic axes and cotyledons expressed the allergens. However, more ara h 1 and ara h 3 messenger RNA was detected in cotyledons relative to embryonic axes. Allergen polypeptide degradation patterns were different in embryonic axes compared with cotyledons during germination and seedling growth, with levels of Ara h 1 and Ara h 2 dramatically reduced compared to the Ara h 3 polypeptides in embryonic axes. These characterization studies of major peanut allergen genes and their corresponding seed storage proteins can provide the basic information needed for biochemical and molecular approaches to obtain a hypoallergenic peanut.

Identification of genes expressed in the Arabidopsis female gametophyte.

The angiosperm female gametophyte typically consists of one egg cell, two synergid cells, one central cell, and three antipodal cells. Each of these four cell types has unique structural features and performs unique functions that are essential for the reproductive process. The gene regulatory networks conferring these four phenotypic states are largely uncharacterized. As a first step towards dissecting the gene regulatory networks of the female gametophyte, we have identified a large collection of genes expressed in specific cells of the Arabidopsis thaliana female gametophyte. We identified these genes using a differential expression screen based on reduced expression in determinant infertile1 (dif1) ovules, which lack female gametophytes. We hybridized ovule RNA probes with Affymetrix ATH1 genome arrays and validated the identified genes using real-time RT-PCR. These assays identified 71 genes exhibiting reduced expression in dif1 ovules. We further validated 45 of these genes using promoter::GFP fusions and 43 were expressed in the female gametophyte. In the context of the ovule, 11 genes were expressed exclusively in the antipodal cells, 11 genes were expressed exclusively or predominantly in the central cell, 17 genes were expressed exclusively or predominantly in the synergid cells, one gene was expressed exclusively in the egg cell, and three genes were expressed strongly in multiple cells of the female gametophyte. These genes provide insights into the molecular processes functioning in the female gametophyte and can be used as starting points to dissect the gene regulatory networks functioning during differentiation of the four female gametophyte cell types.