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Escobar, C.

Publications and source records attributed to Escobar, C..

3 recordsLinked to original sources

Conserved transcriptional reprogramming in nematode infected root cells

Plant-parasitic nematodes are responsible for important annual losses in crop productivity worldwide1,2. Although the formation of feeding organs within the roots is essential for successful sedentary parasitism3, the molecular mechanisms underlying their development are poorly understood. This is partly because these organs originate from a limited number of root cells4-7, making difficult to capture the transcriptional reprogramming that occurs during the early stages of the infection. Here, we first developed a comparative host-pathogen framework to study the nematode infection process in Arabidopsis and rice. Using a cross-species single-cell transcriptomics approach, we identified a unique molecular signature in infected root cells and show that the cellular reprogramming during these early stages is highly conserved across both host-pathogen interactions. This transcriptional cell reprogramming is associated with stemness acquisition related to de novo organogenesis process. By cell-type specific gene regulatory network analysis, we identified AtATHB2/OsHOX28 as an evolutionary conserved and key regulator of the nematode infection process. Loss-of-function of this regulator in both species results in nematode resistance without affecting root growth. This discovery opens up new avenues for the development of sustainable nematode control strategies that could be translated across crop species.

plant biology↗

Lack of food intake during shift work alters the heart transcriptome and leads to cardiac fibrosis and inflammation in rats

Many epidemiological studies revealed that shift work is associated with increased risk of cardiovascular diseases. However, the underlying mechanisms remain poorly understood. An experimental model of shift work in rats has been shown to recapitulate the metabolic disorders observed in human shift workers, and used to demonstrate that restricting food consumption outside working hours prevents shift work-associated obesity and metabolic disturbance. Here we used this model to characterize the effects of shift work in the heart. We show that experimental shift work reprograms the heart cycling transcriptome independently of food consumption. While phases of rhythmic gene expression are distributed across the 24-hour day in control rats, they are clustered towards discrete times in shift workers. Additionally, preventing food intake during shift work affects the expression level of hundreds of genes in the heart. Many of them are found in transcriptional signatures associated with pressure overload and cardiac hypertrophy, and encode for components of the extracellular matrix and inflammatory markers. Consistent with this, the heart of shift worker rats not eating during work exhibits fibrosis and is colonized by immune cells. While maintaining food access during shift work has less effects on gene expression, genes found in transcriptional signatures of cardiac hypertrophy remain affected, and the heart of shift worker rats exhibits fibrosis without inflammation. Together, our findings provide insights into how shift work affects cardiac function, and suggest that some interventions aiming at mitigating metabolic disorders in shift workers may have adverse effects on cardiovascular diseases.

genomics↗

Arabidopsis HIPP27 is a host susceptibility gene for the beet cyst nematode Heterodera schachtii

SummarySedentary plant-parasitic cyst nematodes are obligate biotrophs that infect the roots of their host plant. Their parasitism is based on modification of root cells to form a hypermetabolic syncytium from which the nematodes draw their nutrients. The aim of this study was to identify nematode susceptibility genes in Arabidopsis thaliana and to characterize their roles in supporting the parasitism of Heterodera schachtii. By selecting genes that were most strongly upregulated in response to cyst nematode infection, we identified HIPP27 (HEAVY METAL-ASSOCIATED ISOPRENYLATED PLANT PROTEIN 27) as a host susceptibility factor required for beet cyst nematode infection and development. Detailed expression analysis revealed that HIPP27 is a cytoplasmic protein and that HIPP27 is strongly expressed in leaves, young roots and nematode-induced syncytia. Loss-of-function Arabidopsis hipp27 mutants exhibited severely reduced susceptibility to H. schachtii and abnormal starch accumulation in syncytial and peridermal plastids. Our results suggest that HIPP27 is a susceptibility gene in Arabidopsis whose loss-of-function reduces plant susceptibility to cyst nematode infection without increasing susceptibility to other pathogens or negatively affecting plant phenotype.

plant biology↗