title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=1297 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Postural control in girls with adolescent idiopathic scoliosis while wearing a Chêneau brace or performing active self-correction: a pilot study link: https://peerj.com/articles/7513 last-modified: 2019-08-29 description: BackgroundIt is known that adolescent idiopathic scoliosis (AIS) is often accompanied by balance deficits. This reciprocal relationship must be taken into account when prescribing new therapeutic modalities because these may differently affect postural control, interacting with therapy and influencing its results.ObjectiveThe purpose was to compare postural control in girls with AIS while wearing the Chêneau brace (BRA) or performing active self-correction (ASC) with their postural control in a quiet comfortable stance.MethodsNine subjects were evaluated on a force plate in three series of two 20-s quiet standing trials with eyes open or closed; three blocks were randomly arranged: normal quiet stance (QST), quiet stance with BRA, and quiet stance with ASC. On the basis of centre-of-pressure (COP) recordings, the spatial and temporal COP parameters were computed.Results and DiscussionPerforming ASC was associated with a significant backward excursion of the COP mean position with eyes open and closed (ES = 0.56 and 0.65, respectively; p < 0.05). This excursion was accompanied by an increase in the COP fractal dimension (ES = 1.05 and 0.98; p < 0.05) and frequency (ES = 0.78; p = 0.10 and ES = 1.14; p < 0.05) in the mediolateral (ML) plane. Finally, both therapeutic modalities decreased COP sample entropy with eyes closed in the anteroposterior (AP) plane. Wearing BRA resulted in ES = 1.45 (p < 0.05) while performing ASC in ES = 0.76 (p = 0.13).ConclusionThe observed changes in the fractal dimension (complexity) and frequency caused by ASC account for better adaptability of patients to environmental demands and for their adequate resources of available postural strategies in the ML plane. These changes in sway structure were accompanied by a significant (around 25 mm) backward excursion of the mean COP position. However, this improvement was achieved at the cost of lower automaticity, i.e. higher attentional involvement in postural control in the AP plane. Wearing BRA may have an undesirable effect on some aspects of body balance. creator: Elżbieta Piątek creator: Michał Kuczyński creator: Bożena Ostrowska uri: https://doi.org/10.7717/peerj.7513 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Piątek et al. title: Effects of shading on the growth and leaf photosynthetic characteristics of three forages in an apple orchard on the Loess Plateau of eastern Gansu, China link: https://peerj.com/articles/7594 last-modified: 2019-08-29 description: BackgroundInclusion of forage into the orchard is of great help in promoting the use efficiency of resources, while shading from trees restricts forage growth and production in the Loess Plateau of China. This study was aimed to investigate how tree shading affected leaf trait, photosynthetic gas exchange and chlorophyll feature of forages under the tree in the orchard-forage system.MethodsThe shading treatments were set as partially cutting branches (reduced shading), normal fruit tree shading (normal shading) and normal tree shading plus sun-shading net (enhanced shading) in an apple orchard. Leaf trait, photosynthesis, chlorophyll component and fluorescence related parameters were measured with lucerne (Medicago sativa), white clover (Trifolium repens) and cocksfoot (Dactylis glomerata) which were sown under apple trees.ResultsShading imposed significant impacts on the growth and leaf photosynthetic characteristics, while there were differences among species. Enhanced shading decreased leaf thickness, leaf dry matter content (LDMC) and leaf mass per unit area (LMA). Biomass accumulation decreased with enhanced shading in cocksfoot, but did not change in white clover and lucerne which had much lower biomass accumulation than cocksfoot. Enhanced shading reduced net photosynthetic rate (Pn) of white clover and lucerne, but rarely affected cocksfoot, while it decreased instantaneous water use efficiency (WUEi) of cocksfoot but had few effects on the other forages. Enhanced shading reduced leaf dark respiration rate (Rd), light compensation point (LCP) and maximum assimilation rate. The Rd and LCP of cocksfoot were much lower than those of white clover and lucerne. Chlorophyll contents and chlorophyll a/b changed little with shading. Cocksfoot had the highest contents but lowest ratio. Maximum photochemical rate of photosystem II increased and non-photochemical quenching decreased with enhanced shading in cocksfoot, while did not change in the other forages.DiscussionLeaf trait, photosynthetic gas exchange and chlorophyll feature were variously affected by species, shading and their interaction. Cocksfoot was more efficient than the other two forages in use of weakened light and more tolerant to tree shading. In the apple orchard, we recommend that reducing the density of apple tree or partially cutting branches together with selecting some shading-tolerant forages, i.e., cocksfoot, would be a practical option for the orchard-forage system in the Loess Plateau of China. creator: Mei Yang creator: Minguo Liu creator: Jiaoyun Lu creator: Huimin Yang uri: https://doi.org/10.7717/peerj.7594 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Yang et al. title: Comparative transcriptome analysis of panicle development under heat stress in two rice (Oryza sativa L.) cultivars differing in heat tolerance link: https://peerj.com/articles/7595 last-modified: 2019-08-29 description: Heat stress inhibits rice panicle development and reduces the spikelet number per panicle. This study investigated the mechanism involved in heat-induced damage to panicle development and spikelet formation in rice cultivars that differ in heat tolerance. Transcriptome data from developing panicles grown at 40 °C or 32 °C were compared for two rice cultivars: heat-tolerant Huanghuazhan and heat-susceptible IR36. Of the differentially expressed genes (DEGs), 4,070 heat stress-responsive genes were identified, including 1,688 heat-resistant-cultivar-related genes (RHR), 707 heat-susceptible-cultivar-related genes (SHR), and 1,675 common heat stress-responsive genes (CHR). A Gene Ontology (GO) analysis showed that the DEGs in the RHR category were significantly enriched in 54 gene ontology terms, some of which improved heat tolerance, including those in the WRKY, HD-ZIP, ERF, and MADS transcription factor families. A Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the DEGs in the RHR and SHR categories were enriched in 15 and 11 significant metabolic pathways, respectively. Improved signal transduction capabilities of endogenous hormones under high temperature seemed to promote heat tolerance, while impaired starch and sucrose metabolism under high temperature might have inhibited young panicle development. Our transcriptome analysis provides insights into the different molecular mechanisms of heat stress tolerance in developing rice. creator: Yaliang Wang creator: Yikai Zhang creator: Qiang Zhang creator: Yongtao Cui creator: Jing Xiang creator: Huizhe Chen creator: Guohui Hu creator: Yanhua Chen creator: Xiaodan Wang creator: Defeng Zhu creator: Yuping Zhang uri: https://doi.org/10.7717/peerj.7595 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Wang et al. title: Mapping research trends of retinal vein occlusion from 2009 to 2018: a bibliometric analysis link: https://peerj.com/articles/7603 last-modified: 2019-08-29 description: ObjectivesTo map publication trends and explore research hotspots of retinal vein occlusion (RVO) study.MethodsBased on Web of Science Core Collection (WoSCC), a bibliometric analysis was carried out. The knowledge map was constructed by VOSviewer v.1.6.10 to visualize the annual publication number, the distribution of countries, international collaborations, author productivity, source journals, cited reference and keywords in this field.ResultsA total of 2,135 peer-reviewed papers were retrieved on RVO from 2009 to 2018. The United States ranks highest among countries with the most publications and the most active institution was Kyoto University. Noma H contributed the most publications in this field. Retina—The Journal of Retinal and Vitreous Disease was the most prolific journal in RVO research. The top cited references mainly presented anti-VEGF medications on the management of RVO. The keywords formed six clusters: (1) Risk factors and pathogenesis of RVO; (2) Metabolismof RVO; (3) Therapeutic use of corticosteroids on RVO; (4) Diagnostic methodsof RVO; (5) Management of macular edema secondary to RVO (6) Anti-VEGFtreatment of RVO.ConclusionsThe six major research hotspots could provide an insight into RVO research and valuable information for researchers to identify potential collaborators and partner institutions. creator: Fangkun Zhao creator: Fengkun Du creator: Dong Shi creator: Wenkai Zhou creator: Youhong Jiang creator: Liwei Ma uri: https://doi.org/10.7717/peerj.7603 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Zhao et al. title: Analysis of the laccase gene family and miR397-/miR408-mediated posttranscriptional regulation in Salvia miltiorrhiza link: https://peerj.com/articles/7605 last-modified: 2019-08-29 description: Salvia miltiorrhiza is one of the most commonly used traditional Chinese medicine materials. It contains important bioactive phenolic compounds, such as salvianolic acids, flavonoids and anthocyanins. Elucidation of phenolic compound biosynthesis and its regulatory mechanism is of great significance for S. miltiorrhiza quality improvement. Laccases (LACs) are multicopper-containing enzymes potentially involved in the polymerization of phenolic compounds. So far, little has been known about LAC genes in S. miltiorrhiza. Through systematic investigation of the whole genome sequence and transcriptomes of S. miltiorrhiza, we identified 65 full-length SmLAC genes (SmLAC1–SmLAC65). Phylogenetic analysis showed that 62 of the identified SmLACs clustered with LACs from Arabidopsis and Populus trichocarpa in seven clades (C1–C7), whereas the other three fell into one S. miltiorrhiza-specific clade (C8). All of the deduced SmLAC proteins contain four conserved signature sequences and three typical Cu-oxidase domains, and gene structures of most LACs from S. miltiorrhiza, Arabidopsis and P. trichocarpa were highly conserved, however SmLACs encoding C8 proteins showed distinct intron-exon structures. It suggests the conservation and diversity of plant LACs in gene structures. The majority of SmLACs exhibited tissue-specific expression patterns, indicates manifold functions of SmLACs played in S. miltiorrhiza. Analysis of high-throughput small RNA sequences and degradome data and experimental validation using the 5′ RACE method showed that 23 SmLACs were targets of Smi-miR397. Among them, three were also targeted by Smi-miR408. It suggests the significance of miR397 and miR408 in posttranscriptional regulation of SmLAC genes. Our results provide a foundation for further demonstrating the functions of SmLACs in the production of bioactive phenolic compounds in S. miltiorrhiza. creator: Caili Li creator: Dongqiao Li creator: Hong Zhou creator: Jiang Li creator: Shanfa Lu uri: https://doi.org/10.7717/peerj.7605 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2019 Li et al. title: Tribe reassessment of the subhimalayan leafhopper genus Pseudosubhimalus (Homoptera: Cicadellidae) based on molecular phylogeny link: https://peerj.com/articles/7162 last-modified: 2019-08-28 description: The phylogeny of the Pseudosubhimalus were investigated using of two different data sets, including 91 taxa and 3853 aligned nucleotide positions from the histone H3, 28S rDNA (D2 & D9–10 region). The results suggest the placement of genus in the tribe Ciacadulini, as it was clustered with Cicadulini genera. Relationships between genera of the Cicadulini were strongly supported and leads placement to tribe Cicadulini from Athysanini. Along with this, genus Pseudosubhimalus Ghauri is revised, and P. trilobatus sp. nov. (Himachal Pradesh: Katrain) is added, described from Indian subcontinent and deposited to National Pusa Collection, IARI, New Delhi, with repository number RRS1. creator: GN Niranjana creator: Naresh M. Meshram creator: Pathour R. Shashank creator: Stuti creator: Tahseen Raza Hashmi uri: https://doi.org/10.7717/peerj.7162 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Niranjana et al. title: Cyclodipeptides from Pseudomonas aeruginosa modulate the maize (Zea mays L.) root system and promote S6 ribosomal protein kinase activation link: https://peerj.com/articles/7494 last-modified: 2019-08-28 description: BackgroundPseudomonas aeruginosa is an opportunistic and pathogenic bacterium with the ability to produce cyclodipeptides (CDPs), which belong to a large family of molecules with important biological activities. Excessive amounts of CDPs produced by Pseudomonas strains can activate an auxin response in Arabidopsis thaliana and promote plant growth. Target of rapamycin (TOR) is an evolutionarily conserved eukaryotic protein kinase that coordinates cell growth and metabolic processes in response to environmental and nutritional signals. Target of rapamycin kinase phosphorylates various substrates, of which S6 ribosomal protein kinase (S6K) is particularly well known. The PI3K/Akt/mTOR/S6K signaling pathway has been studied extensively in mammals because of its association with fundamental biological processes including cell differentiation. However, evidences suggest that this pathway also has specific and conserved functions in plants and may thus be conserved, as are several of its components like TOR complex 1 and S6K proteins. In plants, TOR-S6K signaling has been shown to be modulated in response to plant growth promoters or stressors.MethodsIn this study, we evaluated the effects of P. aeruginosa CDPs on the growth and root development of maize plants (Zea mays L.) by adding different CDPs concentrations on culture plant media, as well as the effect on the phosphorylation of the maize S6K protein (ZmS6K) by protein electrophoresis and western blot.ResultsOur results showed that P. aeruginosa CDPs promoted maize growth and development, including modifications in the root system architecture, correlating with the increased ZmS6K phosphorylation and changes induced in electrophoretic mobility, suggesting post-translational modifications on ZmS6K. These findings suggest that the plant growth-promoting effect of the Pseudomonas genus, associated with the CDPs production, involves the TOR/S6K signaling pathway as a mechanism of plant growth and root development in plant–microorganism interaction. creator: Iván Corona-Sánchez creator: Cesar Arturo Peña-Uribe creator: Omar González-López creator: Javier Villegas creator: Jesus Campos-Garcia creator: Homero Reyes de la Cruz uri: https://doi.org/10.7717/peerj.7494 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2019 Corona-Sánchez et al. title: Early Agenian rhinocerotids from Wischberg (Canton Bern, Switzerland) and clarification of the systematics of the genus Diaceratherium link: https://peerj.com/articles/7517 last-modified: 2019-08-28 description: BackgroundWischberg is a Swiss locality in Bern Canton which has yielded numerous vertebrates remains from the earliest Miocene (= MN1). It has a very rich faunal diversity, one of the richest in Switzerland for this age. Among all the mammals reported in the original faunal list 70 years ago, three rhinocerotid species were identified. The material consists of two fragmentary skulls, cranial fragments, several mandibles, teeth and postcranial bones, in a rather good state of preservation.ResultsAfter reexamination of the material from this locality (curated in three different Swiss museums) and comparison with holotype specimens, we show that all rhinocerotid specimens from Wischberg can be referred to two species only. Most of the material can be attributed to the large-sized teleoceratine Diaceratherium lemanense, while only a few specimens, including a skull and mandible, belong to the much smaller sized Pleuroceros pleuroceros. We describe and illustrate for the first time most of these fossil remains. However, the systematics of the genus Diaceratherium is currently controversial, and based on our new observations we consider seven species as valid, though a large-scale phylogenetic study should be done in the future to resolve it. The rhinocerotid association found in Wischberg is nonetheless typical of the MN1 biozone, which results from a faunal renewal occurring just before the end of the Oligocene. creator: Claire Jame creator: Jérémy Tissier creator: Olivier Maridet creator: Damien Becker uri: https://doi.org/10.7717/peerj.7517 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2019 Jame et al. title: Comparative transcriptomics reveals the difference in early endosperm development between maize with different amylose contents link: https://peerj.com/articles/7528 last-modified: 2019-08-28 description: In seeds, the endosperm is a crucial organ that plays vital roles in supporting embryo development and determining seed weight and quality. Starch is the predominant storage carbohydrate of the endosperm and accounts for ∼70% of the mature maize kernel weight. Nonetheless, because starch biosynthesis is a complex process that is orchestrated by multiple enzymes, the gene regulatory networks of starch biosynthesis, particularly amylose and amylopectin biosynthesis, have not been fully elucidated. Here, through high-throughput RNA sequencing, we developed a temporal transcriptome atlas of the endosperms of high-amylose maize and common maize at 5-, 10-, 15- and 20-day after pollination and found that 21,986 genes are involved in the programming of the high-amylose and common maize endosperm. A coexpression analysis identified multiple sequentially expressed gene sets that are closely correlated with cellular and metabolic programmes and provided valuable insight into the dynamic reprogramming of the transcriptome in common and high-amylose maize. In addition, a number of genes and transcription factors were found to be strongly linked to starch synthesis, which might help elucidate the key mechanisms and regulatory networks underlying amylose and amylopectin biosynthesis. This study will aid the understanding of the spatiotemporal patterns and genetic regulation of endosperm development in different types of maize and provide valuable genetic information for the breeding of starch varieties with different contents. creator: Jianzhou Qu creator: Shutu Xu creator: Xiaokang Tian creator: Ting Li creator: Licheng Wang creator: Yuyue Zhong creator: Jiquan Xue creator: Dongwei Guo uri: https://doi.org/10.7717/peerj.7528 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Qu et al. title: The effect of modulating the quantity of enzymes in a model ethanol pathway on metabolic flux in Synechocystis sp. PCC 6803 link: https://peerj.com/articles/7529 last-modified: 2019-08-28 description: Synthetic metabolism allows new metabolic capabilities to be introduced into strains for biotechnology applications. Such engineered metabolic pathways are unlikely to function optimally as initially designed and native metabolism may not efficiently support the introduced pathway without further intervention. To develop our understanding of optimal metabolic engineering strategies, a two-enzyme ethanol pathway consisting of pyruvate decarboxylase and acetaldehyde reductase was introduced into Synechocystis sp. PCC 6803. We characteriseda new set of ribosome binding site sequences in Synechocystis sp. PCC 6803 providing a range of translation strengths for different genes under test. The effect of ribosome-bindingsite sequence, operon design and modifications to native metabolism on pathway flux was analysed by HPLC. The accumulation of all introduced proteins was also quantified using selected reaction monitoring mass spectrometry. Pathway productivity was more strongly dependent on the accumulation of pyruvate decarboxylase than acetaldehyde reductase. In fact, abolishment of reductase over-expression resulted in the greatest ethanol productivity, most likely because strains harbouringsingle-gene constructs accumulated more pyruvate decarboxylase than strains carrying any of the multi-gene constructs. Overall, several lessons were learned. Firstly, the expression level of the first gene in anyoperon influenced the expression level of subsequent genes, demonstrating that translational coupling can also occur in cyanobacteria. Longer operons resulted in lower protein abundance for proximally-encoded cistrons. And, implementation of metabolic engineering strategies that have previously been shown to enhance the growth or yield of pyruvate dependent products, through co-expression with pyruvate kinase and/or fructose-1,6-bisphosphatase/sedoheptulose-1,7-bisphosphatase, indicated that other factors had greater control over growth and metabolic flux under the tested conditions. creator: Paulina Bartasun creator: Nicole Prandi creator: Marko Storch creator: Yarin Aknin creator: Mark Bennett creator: Arianna Palma creator: Geoff Baldwin creator: Yumiko Sakuragi creator: Patrik R. Jones creator: John Rowland uri: https://doi.org/10.7717/peerj.7529 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2019 Bartasun et al.