PMID- 32917129 OWN - NLM STAT- MEDLINE VI - 21 IP - 1 TI - Developmentally regulated activation of defense allows for rapid inhibition of infection in age-related resistance to Phytophthora capsici in cucumber fruit. PG - 628 LA - eng PT - Journal Article PL - England TA - Bmc Genomics JT - BMC genomics JID - 100965258 IS - 1471-2164 (Electronic) LID - 10.1186/s12864-020-07040-9 [doi] FAU - Mansfeld, Ben N AU - Mansfeld BN AD - Graduate Program in Plant Breeding, Genetics and Biotechnology and Department of Horticulture, Michigan State University, 1066 Bogue St, East Lansing, MI, 48824, USA. FAU - Colle, Marivi AU - Colle M AD - Graduate Program in Plant Breeding, Genetics and Biotechnology and Department of Horticulture, Michigan State University, 1066 Bogue St, East Lansing, MI, 48824, USA. FAU - Zhang, Chunqiu AU - Zhang C AD - Graduate Program in Plant Breeding, Genetics and Biotechnology and Department of Horticulture, Michigan State University, 1066 Bogue St, East Lansing, MI, 48824, USA. AD - Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China), Beijing Key Laboratory of Vegetable Germplasm Improvement, National Engineering Research Center for Vegetables, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China. FAU - Lin, Ying-Chen AU - Lin YC AD - Graduate Program in Plant Breeding, Genetics and Biotechnology and Department of Horticulture, Michigan State University, 1066 Bogue St, East Lansing, MI, 48824, USA. FAU - Grumet, Rebecca AU - Grumet R AUID- ORCID: http://orcid.org/0000-0003-3880-9705 AD - Graduate Program in Plant Breeding, Genetics and Biotechnology and Department of Horticulture, Michigan State University, 1066 Bogue St, East Lansing, MI, 48824, USA. grumet@msu.edu. IS - 1471-2164 (Linking) SB - IM MH - Cucumis sativus/*genetics/growth & development/microbiology MH - *Disease Resistance MH - *Gene Expression Regulation, Developmental MH - Gene Expression Regulation, Plant MH - Phytophthora/pathogenicity MH - Transcriptome OTO - NOTNLM OT - Age-related resistance OT - Co-expression networks OT - Cucumber OT - Ontogenic resistance OT - Phytophthora capsici OT - Plant defense OT - Transcriptome PMC - PMC7488727 DCOM- 20210412 LR - 20210412 DP - 2020 Sep 11 DEP - 20200911 AB - BACKGROUND: Age-related resistance (ARR) is a developmentally regulated phenomenon conferring resistance to pathogens or pests. Although ARR has been observed in several host-pathogen systems, the underlying mechanisms are largely uncharacterized. In cucumber, rapidly growing fruit are highly susceptible to Phytophthora capsici but become resistant as they complete exponential growth. We previously demonstrated that ARR is associated with the fruit peel and identified gene expression and metabolomic changes potentially functioning as preformed defenses. RESULTS: Here, we compare the response to infection in fruit at resistant and susceptible ages using microscopy, quantitative bioassays, and weighted gene co-expression analyses. We observed strong transcriptional changes unique to resistant aged fruit 2-4 h post inoculation (hpi). Microscopy and bioassays confirmed this early response, with evidence of pathogen death and infection failure as early as 4 hpi and cessation of pathogen growth by 8-10 hpi. Expression analyses identified candidate genes involved in conferring the rapid response including those encoding transcription factors, hormone signaling pathways, and defenses such as reactive oxygen species metabolism and phenylpropanoid biosynthesis. CONCLUSION: The early pathogen death and rapid defense response in resistant-aged fruit provide insight into potential mechanisms for ARR, implicating both pre-formed biochemical defenses and developmentally regulated capacity for pathogen recognition as key factors shaping age-related resistance.