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Sheath blight (ShB) significantly threatens rice yield production. However, the underlying mechanism of ShB defence in rice remains largely unknown. Here, we identified a highly ShB-susceptible mutant Ds-m which contained a mutation at the ammonium transporter 1;1 (AMT1;1) D

Because glucose is an essential energy source for living organisms, glucose transporters (GLUTs) are present in all species worldwide. Encoded by the solute carrier family 2 gene family, the GLUT proteins generally have 12 transmembrane helices (TMHs). In total, 14 GLUT proteins have been identified in humans (hGLUTs), and they are divided into 3 classes on the basis of their transport characteristics and sequence similarities. Herein, we report the use of protein sequence similarity networks (SSNs) to visualize the sequence trends of 4101 GLUT proteins across the Metazoa. The SSNs separated the metazoan proteins into 3 new classes that were different from the traditional classification system. In the new system, 9 of the 14 hGLUTs (hGLUT1-5, 7, 9, 11, and 14) were grouped into class I, 3 (hGLUT10, 12, and 13) were grouped into class II, and 2 (hGLUT6 and 8) were grouped into class III, as also supported by the phylogenetic tree. Multiple sequence alignments further showed that the conserved residues in each class were different. Furthermore, the hGLUTs in each class showed unique evolutionary characteristics, with similar nonsynonymous-to-synonymous divergence ratios and similar regions under conservative selection pressure. Of note, GLUTs with 3, 6, 18, 24, and 36 TMHs were identified among the metazoan genomes, and 1 Chinese hamster protein with 6 TMHs showed GLUT activity. In summary, this large-scale sequence analysis provided new insights into the classification and evolution of GLUTs and further showed that gene duplication and fusion could have been important drivers during the evolution of these transporter molecules.-Jia, B., Yuan, D. P., Lan, W. J., Xuan, Y. H., Jeon, C. O. New insight into the classification and evolution of glucose transporters in the Metazoa.

Pathogen–host interaction is a complicated process; pathogens mainly infect host plants to acquire nutrients, especially sugars. Rhizoctonia solani, the causative agent of sheath blight disease, is a major pathogen of rice. However, it is not known how this pathogen obtains sugar from rice plants. In this study, we found that the rice sugar transporter OsSWEET11 is involved in the pathogenesis of sheath blight disease. Quantitative real‐time polymerase chain reaction (qRT‐PCR) and β‐d‐glucuronidase expression analyses showed that R. solani infection significantly enhanced OsSWEET11 expression in leaves amongst the clade III SWEET members. The analyses of transgenic plants revealed that Ossweet11 mutants were less susceptible, whereas plants overexpressing OsSWEET11 were more susceptible, to sheath blight compared with wild‐type controls, but the yield of OsSWEET11 mutants and overexpressors was reduced. SWEETs become active on oligomerization. Split‐ubiquitin yeast two‐hybrid, bimolecular fluorescence complementation and co‐immunoprecipitation assays showed that mutated OsSWEET11 interacted with normal OsSWEET11. In addition, expression of conserved residue mutated AtSWEET1 inhibited normal AtSWEET1 activity. To analyse whether inhibition of OsSWEET11 function in mesophyll cells is related to defence against this disease, mutated OsSWEET11 was expressed under the control of the Rubisco promoter, which is specific for green tissues. The resistance of transgenic plants to sheath blight disease, but not other disease, was improved, whereas yield production was not obviously affected. Overall, these results suggest that R. solani might acquire sugar from rice leaves by the activation of OsSWEET11 expression. The plants can be protected from infection by manipulation of the expression of OsSWEET11 without affecting the crop yield.

The Fusarium graminearum species complex (FGSC) is an important group of pathogens distributed in maize-producing areas worldwide. This study investigated the genetic diversity and pathogenicity of 40 FGSC isolates obtained from stalk rot and ear rot samples collected from 42 locations in northeastern China during 2013 and 2014. A phylogenetic tree of translation elongation factor (EF-la) sequences designated the 40 isolates as F. graminearum sensu stricto (67.5%) and F. boothii (32.5%). By using inter-simple sequence repeat analysis (ISSR), it was shown that the isolates were divided into two clades, which corresponded to the species identity of the isolates. However, the isolates from the two different diseases could not be distinguished in pathogenicity. The disease severity index of seedlings inoculated with stalk isolates was slightly higher than that of seedlings inoculated with isolates from infected ears, whereas the pathogenicity of the stalk and ear isolates were identical.