Biology subjects

Wu, J.-L.

Publications and source records attributed to Wu, J.-L..

3 recordsLinked to original sources

bioRxiv2021

Insights into the susceptibility of rice to a floral disease

Crop floral diseases are economically important as they reduce grain yield and quality and even introduce food toxins. Rice false smut has emerged as a serious floral disease producing mycotoxins. However, very little is known on the interaction mechanisms between rice flower and the causal fungus Ustilaginoidea virens. Here we show that a conserved anti-fungal immunity in rice flower is disarmed by U. virens via a secreted protein UvChi1. UvChi1 functioned as an essential virulence factor and directly interacted with the chitin receptor CEBiP and co-receptor CERK1 in rice to disrupt their oligomerizations and subsequent immune responses. Moreover, intraspecific-conserved UvChi1 could target OsCEBiP/OsCERK1 receptor complex in at least 98.5% of 5232 surveyed rice accessions. These results demonstrate that U. virens utilizes a crucial virulence factor to subvert chitin-triggered flower immunity in most rice varieties, providing new insights into the susceptibility of rice to false smut disease. One Sentence SummaryThe fungal pathogen Ustilaginoidea virens disarms chitin-triggered immunity in rice flower via a secreted chitinase.

plant biology↗

bioRxiv2021

Proteasome maturation factor UMP1 confers broad-spectrum disease resistance by modulating H2O2 accumulation in rice

Crops with broad-spectrum resistance (BSR) to diseases are highly desirable in agricultural production. Identification of BSR loci and dissection of the underlying mechanisms are fundamental for crop resistance breeding. Here, we describe the identification and characterization of a rice UMP1 allele, which confers race-nonspecific BSR against blast pathogen Magnaporthe oryzae. OsUMP1 encodes a proteasome maturation factor that contributes to 26S proteasome abundance and activity in rice. Modulation of OsUMP1 expression leads to proteome changes, particularly affects the amounts and activities of H2O2-degrading enzymes. Consequently, H2O2 accumulation and disease resistance are enhanced in OsUMP1-overexpressing rice but reduced in loss-of-function mutants. Elevation of OsUMP1 expression also promotes rice resistance to foliar pathogens Rhizoctonia solani and Xanthomonas oryzae pv. oryzae and a floral pathogen Ustilaginoidea virens without observable yield penalty. These results indicate a BSR pathway linking the proteasome machinery and H2O2 homeostasis, and provide a candidate gene for balancing BSR and yield traits in rice breeding. One Sentence SummaryA natural allele of rice UMP1 promotes resistance to multiple pathogens by boosting H2O2 accumulation.

plant biology↗

bioRxiv2020

Computational approach and functional analysis of Pectobacterium carotovorum subsp. carotovorum low-molecular weight bacteriocin Carocin S2

Pectobacterium carotovorum subsp. Carotovorum 3F3 is a gram-negative phyto-parasitic enterobacterium. This strain is a producer of Carocin S2 bacteriocin, which comprises of two proteins of different sizes. Carocin S2K (killer protein) which is responsible for antibiotic resistance and Carocin S2I (immunity protein) which inhibits the antibiotic activity. The present study aimed to predict the structure and functional properties of Carocin S2. Computational approaches utilizing various bioinformatic tools predicted that Carocin S2 is a putative membrane protein having the N-terminal at the extracellular side and the central domain at the coiled-coil region. Carocin S2 was predicted to have three domains, the translocation domains, receptor binding domain and the killer domain. Moreover, the killer domain was calculated to have the catalytic cleft. The in-vivo assays confirmed that for Carocin S2K, bound immunity protein was not a pre-requisite for cell attachment or translocation. The site-directed mutagenesis experiment led us to hypothesized the hydrolysis mechanism of Carocin S2. The predicted structure of Carocin S2K provided a system of understanding on the biochemical and structural function which led to the mechanism of Carocin S2. It revealed that the role of immunity protein to Carocin S2 is not a pre-requisite for translocation pathway. Furthermore, this research led to hypothesized a hydrolytic mechanism of Carocin S2 to target the tRNA.

biochemistry↗