Knock-out of BnHva22c reduces the susceptibility of Brassica napus to infection with the fungal pathogen Verticillium longisporum

Verticillium longisporum(Vl43)is a soilborne hemibiotrophic fungal pathogen causing stem striping on oilseed rape(OSR)and severe yield losses.Breeding for resistant varieties is the most promising approach to control this disease.Here,we report the identification of Hva22c as a novel susceptibility factor and its potential for improving OSR resistance.Hva22c is a member of the Hva22 gene family,originally described for barley(Hordeum vulgare).Several Hva22 members have been located at the endoplasmic reticulum.Hva22c is up-regulated in response to Vl43 in both Arabidopsis and OSR.We demonstrate that knock-out of Hva22c in OSR by CRISPR/Cas9 and its homolog in Arabidopsis by T-DNA insertion reduced plants’susceptibility to Vl43 infection and impaired the development of disease symptoms.To understand the underlying mechanism,we analysed transcriptomic data from infected and non-infected roots of hva22c knock-out and wild type plants.We identified a homozygous mutant with frame-shifts in all four BnHva22c loci displaying a vastly altered transcriptional landscape at 6 dpi.Significantly,a large set of genes was suppressed under mock conditions including genes related to the endomembrane systems.Among the up-regulated genes we found several defense-related and phytohormone-responsive genes when comparing mutant to the wild type.These results demonstrate that Hva22c is functionally required for a fully compatible plant-fungus interaction.Its loss of function reduces plant susceptibility,most likely due to endoplasmatic reticulum and Golgi dysfunction accompanied by additionally activated defense responses.These findings can help improve OSR resistance to V.longisporum infection.

Discipline Impact Factor: Some of Its History, Some of the Author's Experience of Its Application, the Continuing Reasons for Its Use and… Next Beyond

Purpose: This work aims to consider the role and some of the 42-year history of the discipline impact factor(DIF) in evaluation of serial publications. Also, the original "symmetric" indicator called the "discipline susceptibility factor" is to be presented. Design/methodology/approach: In accordance with the purpose of the work, the methods are analytical interpretation of the scientific literature related to this problem as well as speculative explanations. The information base of the research is bibliometric publications dealing with impact, impact factor, discipline impact factor, and discipline susceptibility factor.Findings: Examples of the DIF application and modification of the indicator are given. It is shown why research and university libraries need to use the DIF to evaluate serials in conditions of scarce funding for subscription to serial publications, even if open access is available. The role of the DIF for evaluating journals by authors of scientific papers when choosing a good and right journal for submitting a paper is also briefly discussed. An original indicator "symmetrical" to the DIF(the "discipline susceptibility factor") and its differences from the DIF in terms of content and purpose of evaluation are also briefly presented.Research limitations: The selection of publications for the information base of the research did not include those in which the DIF was only mentioned, used partially or not for its original purpose. Restrictions on the length of the article to be submitted in this special issue of the JDIS also caused exclusion even a number of completely relevant publications. Consideration of the DIF is not placed in the context of describing other derivatives from the Garfield impact factor. Practical implications: An underrated bibliometric indicator, viz. the discipline impact factor is being promoted for the practical application. An original indicator "symmetrical" to DIF has been proposed in order of searching serial publications representing the external research fields that might fit for potential applications of the results of scientific activities obtained within the framework of the specific research field represented by the cited specialized journals. Both can be useful in research and university libraries in their endeavors to improve scientific information services. Also, both can be used for evaluating journals by authors of scientific papers when choosing a journal to submit a paper.Originality/value: The article substantiates the need to evaluate scientific serial publications in library activities—even in conditions of access to huge and convenient databases(subscription packages) and open access to a large number of serial publications. It gives a mini-survey of the history of one of the methods of such evaluation, and offers an original method for evaluating scientific serial publications.

All Roads Lead to Susceptibility: The Many Modes of Action of Fungal and Oomycete Intracellular Effectors

The ability to secrete effector proteins that can enter plant cells and manipulate host processes is a key determinant of what makes a successful plant pathogen.Here,we review intracellular effectors from filamentous(fungal and oomycete)phytopathogens and the host proteins and processes that are targeted to promote disease.We cover contrasting virulence strategies and effector modes of action.Filamentous pathogen effectors alter the fates of host proteins that they target,changing their stability,their activity,their location,and the protein partners with which they interact.Some effectors inhibit target activity,whereas others enhance or utilize it,and some target multiple host proteins.We discuss the emerging topic of effectors that target negative regulators of immunity or other plant proteins with activities that support susceptibility.We also highlight the commonly targeted host proteins that are manipulated by effectors from multiple pathogens,including those representing different kingdoms of life.