Genome-wide identification of the oatMLOfamily and identification of a candidateAsMLOassociated with powdery mildew susceptibility

Abstract

Blumeria graminis f. spp. avenae, is the causal agent of powdery mildew disease in oats (Avena sativa). It is the most significant limiting factor to oat production, with yield losses ranging from 5%-40%, during high disease pressure conditions. Certain members of the Mildew Locus O (MLO) gene family have been shown to act as powdery mildew susceptibility factors in many different plant species. A loss-of-function mutation of specific MLO genes confers broad-spectrum resistance against powdery mildew pathogens. Potential MLO candidates have not yet been identified in oats. In this study, we identified oat MLOs by querying 341 known MLO protein sequences against the publicly available oat genome. 11 MLO-like sequences were identified in oats. Phylogenetic analysis grouped these candidates into four different clades, one of which, AsMLO1 was grouped together with other cereal MLOs functionally known to contribute to powdery mildew susceptibility. AsMLO1 showed the highest similarity to the known powdery mildew-associated MLO proteins from wheat and barley. Gene expression analysis revealed AsMLO1 expression is up regulated at 12 hours post-infection with Bga and was inferred to be a candidate gene associated with powdery mildew susceptibility in oats. These results are an important step towards more durable strategies to control powdery mildew incidence and severity in oats.

Genetic mapping of the powdery mildew resistance gene Pm13 on oat chromosome 1D

“…MLO is a powdery mildew susceptibility gene that was initially identified in barley but that is broadly conserved across plant species (Appiano et al, 2015; Jørgensen, 1992). In oats, several MLO-like genes have been identified based on sequence homologies (Reilly et al, 2021), but their functionality has not been shown yet. Taken together, even though several intriguing putative functions of Pm13 have been identified, they remain speculative and additional efforts are necessary to fine map and clone Pm13.…”

Selection and Evaluation of Reference Genes for Quantitative Real-Time PCR in Tomato (Solanum lycopersicum L.) Inoculated with Oidium neolycopersici

“…EF1α was used as a reference gene for eggplant and petunia [51,52]. Tubulin was used as a reference gene for studying the mulberry [53], and 28SrRNA was used as a reference gene for studying the oat [54]. The reference genes used to investigate the functional gene expression profiles associated with tomato PM are also different.…”

Era-like GTP protein gene expression in rice

“…These enzymes do not share arrangements with any other known GPCR. The 7TM domain structure has been biochemically confirmed for one MLO from oat (Reilly et al, 2021). Researches told that Arabidopsis consists of only one canonical GTP gene i.e.…”

“…GTP-binding activities and substrates for ADP ribosylation catalyzed by pertussis toxin were detected in gel filtration fractions of extracts from pea (Pisum sativum) and Lemna paucicostata (Schneider et al, 2005). A filter assay has been used to uncover small GTP binding proteins in the green alga (Sasaki and Burr, 2000), in microsomes of zucchini (Cucurbita pepo) hypocotyl (Reilly et al, 2021), in chloroplast outer envelope membrane and nuclear envelope from pea (Youssefian et al, 1993a). In 2015, in the cytosol of pea plumule cells ARF-like protein was discovered by Rout and Panigrahi.…”