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Alternative polyadenylation (APA) is an important contributor to the regulation of gene expression in plants. One subunit of the complex that cleaves and polyadenylates mRNAs in the nucleus, CPSF30 (for the 30 kD subunit of the mammalian Cleavage and Polyadenylation Specificity Factor), has been implicated in a wide-ranging network of regulatory events. CPSF30 plays roles in root development, flowering time, and response to biotic and abiotic stresses. CPSF30 also is a conduit that links cellular signaling and RNA modification with alternative RNA processing events and transcriptional dynamics. While much is known about CPSF30 and its roles in plants, questions remain regarding the connections between CPSF30-mediated APA and the downstream events that lead to specific phenotypic outcomes. To address these, we conducted a detailed analysis of poly(A) site usage in the CPSF30 mutant. Our results corroborate earlier reports that link CPSF30 with a distinctive cis element (AAUAAA) that is present 10-30 nts upstream of some, but not all, plant pre-mRNAs. Interestingly, our results reveal a distinctive shift in poly(A) site in mutants deficient in CPSF30, resulting in cleavage and polyadenylation at the location of motifs similar to AAUAAA. Importantly, CPSF30-associated APA had at best a small impact on mRNA functionality. These results necessitate the formulation of new hypotheses for mechanisms by which CPSF30-mediated APA influences physiological processes. 

Abstract Previous reports indicate variable soybean quality parameters exported from different geographic regions. This review compares soybean and soybean co‐products grown under diverse environmental conditions. While numerous studies have been conducted on whole soybean and soybean meal (SBM) composition by origin, similar analysis of soybean oil is lacking. This review has two objectives: 1) summarize soybean and SBM quality by origin using a meta‐analysis approach, and 2) analyze collected crude degummed soybean oil samples that originate from the US, Brazil and Argentina for key quality attributes. Soybeans from Brazil have higher levels of protein (P < 0.05) than US soybeans, but US soybeans have lower heat damage (P < 0.05) and total damage (P < 0.05) than soybeans from Brazil. US and Brazil SBM have higher crude protein (CP) (P < 0.05) than SBM from Argentina. At equal CP content, US SBM had less fiber (P < 0.0001), more sucrose (P < 0.0001) and lysine (P < 0.0001) and better protein quality than South American SBMs. Methionine, threonine, and cysteine levels were similar in soybean protein from US and Argentina and higher than that in soybean protein from Brazil. Crude degummed soybean oil from Brazil had more (P < 0.05) free fatty acids, neutral oil loss, phosphorus, calcium and magnesium than crude degummed soybean oil from the US or Argentina. Our analysis suggests that environmental conditions under which soybeans are grown, stored, and handled can have a large impact on chemical composition and nutrient quality of soybean meal and soybean oil. 

Abstract Systemic acquired resistance (SAR), a type of long-distance immunity in plants, provides long-lasting resistance to a broad spectrum of pathogens. SAR is thought to involve the rapid generation and systemic transport of a mobile signal that prepares systemic parts of the plant to better resist future infections. Exploration of the molecular mechanisms underlying SAR have identified multiple mobile regulators of SAR in the last few decades. Examination of the relationship among several of these seemingly unrelated molecules depicts a forked pathway comprising at least two branches of equal importance to SAR. One branch is regulated by the plant hormone salicylic acid (SA), and the other culminates (based on current knowledge) with the phosphorylated sugar derivative, glycerol-3-phosphate (G3P). This review summarizes the activities that contribute to pathogen-responsive generation of SA and G3P and the components that regulate their systemic transport during SAR. 

The plant cuticle is often considered a passive barrier from the environment. We show that the cuticle regulates active transport of the defense hormone salicylic acid (SA). SA, an important regulator of systemic acquired resistance (SAR), is preferentially transported from pathogen-infected to uninfected parts via the apoplast. Apoplastic accumulation of SA, which precedes its accumulation in the cytosol, is driven by the pH gradient and deprotonation of SA. In cuticle-defective mutants, increased transpiration and reduced water potential preferentially routes SA to cuticle wax rather than to the apoplast. This results in defective long-distance transport of SA, which in turn impairs distal accumulation of the SAR-inducer pipecolic acid. High humidity reduces transpiration to restore systemic SA transport and, thereby, SAR in cuticle-defective mutants. Together, our results demonstrate that long-distance mobility of SA is essential for SAR and that partitioning of SA between the symplast and cuticle is regulated by transpiration.