Project description:Germination of seeds of Orobanche species requires specific chemicals exuded by host roots. A family of “divergent” KARRIKIN INSENSITIVE2 (KAI2d) genes encode proteins that recognize strigolactone (SL) class germination simulants. We explored specificity of germination stimulant detection by analyzing interspecific segregants of a cross between Orobanche cernua and O. cumana, closely related species that differ in stimulant response. O. cernua parasitizes tomato and germinates in response to the SL orobanchol, while O. cumana parasitizes sunflower and responds to dehydrocostus lactone (DCL). KAI2d genes were catalogued in parents and in segregants that showed stimulant specificity. KAI2d genes were also functionally assayed in the Arabidopsis kai2 mutant background. We identified five full-length KAI2d genes in O. cernua and eight in O. cumana. The O. cernua KAI2d2, as well as its ortholog in O. cumana, are associated with SL perception. A cluster of O. cumana KAI2d genes was genetically linked to DCL perception, although no specific receptor gene was identified by heterologous complementation. These findings support the KAI2d-mediated perception of SLs, but fall short of explaining how O. cumana perceives DCL. The ability of some O. cumana KAI2d genes to detect SLs points to the involvement of additional factors in regulating stimulant specificity.
Project description:We used tomato pollen in order to identify pollen stage-specific small non-coding RNAs (sncRNAs) and their target mRNAs. We further deployed elevated temperatures to discern stress responsive sncRNAs. For this purpose high throughput sncRNA-sequencing was performed for three-replicated sncRNAs libraries derived from tomato tetrad, post-meiotic, and mature pollen under control and heat stress conditions.
Project description:High-throughput sequence analysis of small RNAs of TYLCV-tolerant (containing tolerance gene Ty-1) and susceptible varieties indicated that miRNA-like vsRNAs and secondary vsiRNAs are mainly contributed to hotpots. Interestingly, various characteristics of vsRNAs among each sample are consistent, but in different number of expression; Deep sequencing of degradome provided evidence for the function of vsRNAs-mediated viral transcripts slicing; And bisulfite sequencing PCR suggested the geminivirus DNA methylation induced by vsRNAs. Comparison of the expression quantity and trend of viral DNA, mRNA and vsRNA inferred that the quantity of vsRNAs is significantly corresponding to the expression level of viral mRNA. Nevertheless, vsRNAs had finite effect on inhibition of virus replication and expression. Here, we also speculated that by RDR catalysis of vsRNAs amplification, the tolerance gene Ty-1 may take an effective inhibition of viral transcription at the beginning of TYLCV infection. Examination of 6 different sRNA and 4 degradome library in 2 tomato material. The main result of our paper is distinguish the host plant sRNA and viral-derived sRNA from the .fa files (MMS_21dpi, 30dpi and TY1S_21dpi, 30dpi).
Project description:To test the hypothesis that gene expression by the fungal partner in this beneficial interaction is modulated by the plant host, Trichoderma virens was co-cultured with maize or tomato in a hydroponic system allowing interaction with the roots. The transcriptomes for T. virens alone were compared with fungus-inoculated tomato or maize roots by hybridization on oligonucleotide microarrays Based on the relevant role of Trichoderma virens as a biological control agent this study provides a better knowledge of its crosstalk with plants in a host-specific manner. Trichoderma virens was co-cultured for three days with maize or tomato in a hydroponic system allowing interaction with the roots. 3 experiments were performed for each treatment, and compared to 5 experiments with T. virens grown under the same conditions without plants.
Project description:Recently, we demonstrated that RDRs had a general function to synthesize antisense RNAs from sense transcripts of protein-coding genes. In this study, we analyzed whether RDR-mediated antisense RNAs were processed into small RNAs by deep sequencing using SOLiD. Deep sequencing identified 1,645 RDR1/2/6-mediated smRNA loci in drought stress and control conditions.