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The transcription factor is an essential factor for regulating the responses of plants to external stimuli. The WRKY protein is a superfamily of plant transcription factors involved in response to various stresses (e.g., cold, heat, salt, drought, ions, pathogens, and insects). During angiosperm evolution, the number and function of WRKY transcription factors constantly change. After suffering from long-term environmental battering, plants of different evolutionary statuses ultimately retained different numbers of WRKY family members. The WRKY family of proteins is generally divided into three large categories of angiosperms, owing to their conserved domain and three-dimensional structures. The WRKY transcription factors mediate plant adaptation to various environments via participating in various biological pathways, such as ROS (reactive oxygen species) and hormone signaling pathways, further regulating plant enzyme systems, stomatal closure, and leaf shrinkage physiological responses. This article analyzed the evolution of the WRKY family in angiosperms and its functions in responding to various external environments, especially the function and evolution in Magnoliaceae plants. It helps to gain a deeper understanding of the evolution and functional diversity of the WRKY family and provides theoretical and experimental references for studying the molecular mechanisms of environmental stress. [ABSTRACT FROM AUTHOR]

Sesquiterpenes are important defensive secondary metabolites that are synthesized in various plant organs. Methyl jasmonate (MeJA) plays a key role in plant defense responses and secondary metabolism. Sindora glabra Merr. ex de Wit produces abundant sesquiterpenes in its trunks, and was subjected to investigation after MeJA treatment in order to characterize the molecular mechanisms underlying the regulation of sesquiterpene biosynthesis in plant stems and further our understanding of oleoresin production in trees. A total of 14 types of sesquiterpenes in the stems of mature S. glabra trees were identified. The levels of two sesquiterpenes, α-copaene and β-caryophyllene, significantly increased after MeJA treatment. Differentially expressed genes involved in terpenoid backbone biosynthesis were significantly enriched over time, while the expression of JAZ genes involved in the jasmonic acid signaling pathway and TGA genes involved in the salicylic acid signaling pathway was significantly enriched at later time points after treatment. Two new terpene synthase genes, SgSTPS4 and SgSTPS5 , were also identified. Following MeJA treatment, the expression levels of SgSTPS1 , SgSTPS2 and SgSTPS4 decreased, while SgSTPS5 expression increased. The major enzymatic products of SgSTPS4 were identified as β-elemene and cyperene, while SgSTPS5 was identified as a bifunctional mono/sesquiterpene synthase that could catalyze farnesyl pyrophosphate to produce nine types of sesquiterpenes, including α-copaene and β-caryophyllene, while SgSTPS5 could also use geranyl pyrophosphate to produce geraniol. Dramatic changes in the amounts of α-copaene and β-caryophyllene in response to MeJA were correlated with transcriptional expression changes of SgSTPS5 in the wood tissues. In addition, the transcription factors MYB, NAC, ARF, WRKY, MYC, ERF and GRAS were co-expressed with terpene biosynthesis genes and might potentially regulate terpene biosynthesis. Metabolite changes were further investigated with UPLC-TOF/MS following MeJA treatment. These results contribute to the elucidation of the molecular mechanisms of terpene biosynthesis and regulation as well as to the identification of candidate genes involved in these processes. [ABSTRACT FROM AUTHOR]

Congenital obstructive nephropathy is amongst the main causes of chronic renal failure in children. Early diagnosis and initiation of the treatment will delay progressive renal tubular atrophy and interstitial fibrosis with the loss of nephrons. The aim of this study was to evaluate whether urinary (u) semaphorin-3A (SEMA-3A) and Netrin-1 may be potential biomarkers in children with congenital hydronephrosis due to ureteropelvic junction obstruction (UPJO). The study consisted of 42 children with severe hydronephrosis who needed surgery and two control groups (Control One: 42 children with mild, non-obstructive hydronephrosis; Control Two: 44 healthy children). All children had normal renal function. Urinary semaphorin-3A and Netrin-1 levels were measured in different groups using immunoenzymatic ELISA commercial kits. Compared with Control One and Control Two groups, the preoperative median uSEMA-3A/creatinine (cr.) and uNetrin-1/cr. levels increased significantly in the children with severe hydronephrosis (p < .01). One month after surgery, uSEMA-3A/cr. and uNetrin-1/cr. levels had decreased significantly in the children with severe hydronephrosis (p < .01), but were still higher than those in both control groups (p < .05). Receiver operator characteristic (ROC) analyses revealed a good diagnostic profile for uSEMA-3A and uNetrin-1 in terms of identifying children with a differential renal function of <40% [area under the curve (AUC) 0.825 and 0.745, respectively]. Our results indicate that increased concentrations of uSEMA-3A and uNetrin-1 are found in urine from children with severe hydronephrosis and that their concentrations are related to the degree of obstruction. [ABSTRACT FROM AUTHOR]

Understanding the ecological processes that regulate microbial community assembly in different habitats is critical to predict microbial responses to anthropogenic disturbances and environmental changes. Rubber (Hevea brasiliensis) and Eucalypt (Eucalyptus urophylla) plantations (thereafter RP and EP) are rapidly established at the expense of forests in tropical China, greatly affecting tropical soils and their processes. However, the assembly processes of soil microbial communities after forest conversions remain unclear. We investigated soil microbial communities' attributes and quantified the portion of deterministic assembly variation in two RP (a 3- and a 5-year-old) and two EP (a 2- and a 4-year-old) in Southern China. Shannon and Faith's Phylogenetic α-diversity of both bacterial and fungal communities were higher in RP than in EP, regardless of plantation age or soil depth (0–50 cm). Bacterial and fungal community structure was significantly different among the four plantations. The dominant microbial taxa in RP closely tracked the availability of nitrogen, phosphorus and potassium (K) while those in EP were closely related to the high total K content. Microbial co-occurrence networks in RP were more modular than those in EP, as governed by more keystone taxa that were strongly dependent on soil available nutrients. Environmental filtering imposed by soil nutrients heterogeneity contributed a considerable portion (33–47%) of bacterial assembly variation in RP, but much less (8–14%) in EP. The relative contribution of environmental selection on fungal assembly was also greater in RP than in EP. Our findings suggest that in RP clear microbial community patterns exist with respect to soil nutrients, whereas in EP microbial community assembly patterns are more stochastic and variable. The large variation in soil microbial community assembly patterns in EP could lead to fragile and unstable microbial-soil relationships, which may be one factor driving soil degradation in EP. [ABSTRACT FROM AUTHOR]

The production of knot-free and high-quality wood can be a vital issue in silviculture and forest management. In this study, knot properties, branch occlusion, and wood discoloration were investigated in an 11-year-old Mytilaria laosensis plantation in Guangxi, China, to examine the effectiveness of natural pruning in reducing knot-related defects. A total of 1513 occluded branches from 20 trees were sampled and dissected. Occluded branches were most common at heights of 2–6 m, and the mean diameter of the occluded branches gradually increased with height from the base to 6 m. Linear and generalized linear mixed-effect models were developed to reveal the relationship between branch occlusion and discoloration. The mortality of branches was highest in the third and fourth year and it took roughly three to six years to occlude. The mixed-models indicated that the branch occlusion time was positively correlated with the occluded branch diameter and dead branch stub length, and negatively correlated with the stem radial increment during branch occlusion. Branch discoloration was positively correlated with the occluded branch diameter and branch occlusion time, and was negatively correlated with the branch angle. The probability of wood discoloration also increased with the branch occlusion time. Our findings contribute to a better understanding of the spatiotemporal allocation and internal characteristics of occluded branches, and provide a reference for growing high-quality M. laosensis wood. [ABSTRACT FROM AUTHOR]