Edited by Tamas DalmayKeywords: Tomato miR156 Plant architecture Inflorescence structure Fruit development a b s t r a c t Plant microRNAs (miRNAs) are vital components of the translation control system that regulates plant development and reproduction. The biological function of sly-miR156 was investigated by over-expression in tomato plants. Transgenic tomato plants exhibited a drastically altered phenotype, with reduced height, smaller but more numerous leaves, and smaller fruit. The inflorescence structure of sly-miR156 over-expressing plants phenocopied the sft mutant. The putative targets of sly-miR156 were identified by data base search and included six SQUAMOSA PROMOTER BINDING PROTEIN (SBP)-box transcription factor genes. Their expression patterns were then determined in 35S-miR156a and wild type tomato plants. These target genes, as well as the tomato FLOWERING LOCUS T (FT) ortholog SFT, were significantly down-regulated in sly-miR156 over-expressing plants. These studies reveal novel phenotypes regulated by miR156.

Expression of artificial microRNAs (amiRNAs) in plants can target and degrade the invading viral RNA, consequently conferring virus resistance. Two amiRNAs, targeting the coding sequence shared by the 2a and 2b genes and the highly conserved 3' untranslated region (UTR) of Cucumber mosaic virus (CMV), respectively, were generated and introduced into the susceptible tomato. The transgenic tomato plants expressing amiRNAs displayed effective resistance to CMV infection and CMV mixed with non-targeted viruses, including tobacco mosaic virus and tomato yellow leaf curl virus. A series of grafting assays indicate scions originated from the transgenic tomato plant maintain stable resistance to CMV infection after grafted onto a CMV-infected rootstock. However, the grafting assay also suggests that the amiRNA-mediated resistance acts in a cell-autonomous manner and the amiRNA signal cannot be transmitted over long distances through the vascular system. Moreover, transgenic plants expressing amiRNA targeting the 2a and 2b viral genes displayed slightly more effective to repress CMV RNA accumulation than transgenic plants expressing amiRNA targeting the 3' UTR of viral genome did. Our work provides new evidence of the use of amiRNAs as an effective approach to engineer viral resistance in the tomato and possibly in other crops.

Overexpression of rice OsPGIP2 in Brassica napus results in resistance to Sclerotinia sclerotiorum by increasing activation of defense mechanisms and inhibiting fungal SsPG3 and SsPG6 proteins.

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Cattle are raised around the world and are frequently exposed to heat stress, whether in tropical countries or in regions with temperate climates. It is universally acknowledged that compared to those in temperate areas, the cattle breeds developed in tropical and subtropical areas have better heat tolerance. However, the underlying mechanism of heat tolerance has not been fully studied, especially from the perspective of intestinal microbiomics. The present study collected fecal samples of cattle from four representative climatic regions of China, namely, the mesotemperate (HLJ), warm temperate (SD), subtropical (HK), and tropical (SS) regions. Then, the feces were analyzed using high-throughput 16S rRNA sequencing. The results showed that with increasing climatic temperature from HLJ to SS, the abundance of Firmicutes increased, accompanied by an increasing Firmicutes to Bacteroidota ratio. Proteobacteria showed a trend of reduction from HLJ to SS. Patescibacteria, Chloroflexi, and Actinobacteriota were particularly highest in SS for adapting to the tropical environment. The microbial phenotype in the tropics was characterized by an increase in Gram-positive bacteria and a decrease in Gram-negative bacteria, aerobic bacteria, and the forming of_biofilms. Consistently, the functional abundances of organismal systems and metabolism were decreased to reduce the material and energy demands in a hot environment. Genetic information processing and information storage and processing may be how gut flora deals with hot conditions. The present study revealed the differences in the structure and function of gut microbes of cattle from mesotemperate to tropical climates and provided an important reference for future research on the mechanism of heat tolerance regulated by the gut microbiota and a potential microbiota-based target to alleviate heat stress.

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In this paper, biodegradable polycaprolactone (PCL) was used as the raw material to prepare micro/nanofibrous polycaprolactone membrane (PCLM) through solution blow spinning (SBS) technology. The effects of spinning conditions (distance, gas pressure, and spinning solution concentration) on PCLM structures were investigated. The obtained membranes were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, water contact angle, and thermogravimetric analysis instrument. The oil adsorbency and reusability of PCLM were measured. The oil adsorption capacity of PCLM for motor oil, peanut oil, and diesel oil was 15.93, 14.81, and 12.86 g·g−1, respectively. After 10 times of reuse, the adsorption capacity for motor oil, peanut oil, and diesel oil could still remain at about 80% of the first cycle. The kinetic and thermodynamic studies showed that the adsorption conformed to the first‐order kinetic model and Freundlich model. Thermodynamic parameters for oil adsorption ΔGθ, ΔHθ, and ΔSθ indicated the oil adsorption of PCLM was a spontaneous and physisorption process.