The process of RNA splicing influences many physiological processes, including plant immunity. However, how plant parasites manipulate host RNA splicing process remains unknown. Here we demonstrate that PsAvr3c, an avirulence effector from oomycete plant pathogen Phytophthora sojae, physically binds to and stabilizes soybean serine/lysine/arginine-rich proteins GmSKRPs. The SKRPs are novel proteins that associate with a complex that contains plant spliceosome components, and are negative regulators of plant immunity. Analysis by RNA-seq data indicates that alternative splicing of pre-mRNAs from 401 soybean genes, including defense-related genes, is altered in GmSKRP1 and PsAvr3c overexpressing lines compared to control plants. Representative splicing events mediated by GmSKRP1 and PsAvr3c are tested by infection assays or by transient expression in soybean plants. Our results show that plant pathogen effectors can reprogram host pre-mRNA splicing to promote disease, and we propose that pathogens evolved such strategies to defeat host immune systems.

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bCrystal toxin Cry1Ca from Bacillus thuringiensis has an insecticidal spectrum encompassing lepidopteran insects that are tolerant to current commercially used B. thuringiensis crops (Bt crops) expressing Cry1A toxins and may be useful as a potential bioinsecticide. The mode of action of Cry1A is fairly well understood. However, whether Cry1Ca interacts with the same receptor proteins as Cry1A remains unproven. In the present paper, we first cloned a cadherin-like gene, SeCad1b, from Spodoptera exigua (relatively susceptible to Cry1Ca). SeCad1b was highly expressed in the larval gut but scarcely detected in fat body, Malpighian tubules, and remaining carcass. Second, we bacterially expressed truncated cadherin rSeCad1bp and its interspecific homologue rHaBtRp from Helicoverpa armigera (more sensitive to Cry1Ac) containing the putative toxin-binding regions. Competitive binding assays showed that both Cry1Ca and Cry1Ac could bind to rSeCad1bp and rHaBtRp, and they did not compete with each other. Third, Cry1Ca ingestion killed larvae and decreased the weight of surviving larvae. Dietary introduction of SeCad1b double-stranded RNA (dsRNA) reduced approximately 80% of the target mRNA and partially alleviated the negative effect of Cry1Ca on larval survival and growth. Lastly, rSeCad1bp and rHaBtRp differentially enhanced the negative effects of Cry1Ca and Cry1Ac on the larval mortalities and growth of S. exigua and H. armigera. Thus, we provide the first lines of evidence to suggest that SeCad1b from S. exigua is a functional receptor of Cry1Ca.

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A case study at the Baihetan dam site was undertaken to obtain a representative volume element (RVE) size. Two-dimensional fracture information in an exploration tunnel was used to generate a large threedimensional fracture network. By dividing the entire modeled rock mass into cubes, the volumetric fracture density (P 32 ) value of each cube was determined. The size effect can be determined by changing the cube size. The RVE was determined using P 32 calculation and statistical tests, including Kolmogorov-Smirnov (KS) and Wilcoxon rank-sum tests. The P 32 value depends on the geometrical parameters of fracture density and size; in this study, this value is called the geometrical RVE. P 32 is dependent on fracture density and size, and cannot appropriately reflect certain data such as fracture dip or dip angle. Therefore, we propose a structural RVE (SRVE) considering fracture dip direction, dip angle, density, and size, which together constitute the available information about the fracture network. Therefore, the SRVE is more applicable for use in solving geological problems than the RVE. In this analysis, the KS and Wilcoxon rank-sum tests were used to determine the SRVE size. Keywords Representative volume element Á Size effect Á Statistical test Á Three-dimensional fracture network Abbreviations K Fisher constant KS Kolmogorov-Smirnov test P 21 Total length of fracture traces per unit area (m/m 2 ) P 32 Fracture area per rock volume (m 2 /m 3 ) RVE Representative volume element SRVE Structural representative volume elementV Cube volume (m 3 ) h Acute angle between the scanline and the line normal to the mean orientation of the joint set (°) N Cube number L Length of the overall rock mass (m) W Width of the overall rock mass (m) H Height of the overall rock mass (m) l Serial number of the cube in the x direction m Serial number of the cube in the y direction n Serial number of the cube in the z direction x 0 X-coordinate of a fracture disc center (m) y 0 Y-coordinate of a fracture disc center (m) z 0 Z-coordinate of a fracture disc center (m) a Dip angle (°) b Dip direction (°) (A, B, C) Normal vector of a fracture plane D Fracture disc diameter (m) D-stat Statistic of Kolmogorov-Smirnov test S i (x i )

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driven range expansion of a temperate-originated plant to pan-tropic under global change. Ecological Monographs 91(2):e01445.