Transcriptome analysis of Arabidopsis thaliana plants in response to kin and stranger recognition

Abstract

IntroductionKin recognition in plants is a phenomenon that has recently gained attention in the ecology and plant biology fields as more evidence for these interactions has accumulated. Dudley and File 1 were the first to demonstrate kin recognition in plants through their experiments with Cakile edentula. In their work, C. edentula plants were grown in pots with strangers (plants that were not related) or with kin (plants grown from seed collected from the same mother). Dudley and File 1 found that plants grown with strangers allocated significantly more root mass as compared with plants grown with kin, indicating that the C. edentula plants could not only sense the relatedness of their pot neighbors, but also alter their growth according to the relatedness. In another study with Impatiens pallida, it was found that plants grown with strangers increased allocation in stems and leaves vs. when grown in the presence of kin.2 This study established that another plant species has the ability to alter growth in response to the identity of neighbors, although the response differs between species.Motivated by these studies Biedrzycki et al. 3 examined whether similar kin recognition existed in the model species Arabidopsis thaliana as well whether a root derived chemical may be involved in this response. This study differed from the previously mentioned reports in that plants were grown in liquid growth media in tissue culture plates rather than soil and pots and plants were exposed only to the media that contained secretions (secondary metabolite compound released by plant roots recent reports have demonstrated that Arabidopsis thaliana has the ability to alter its growth differentially when grown in the presence of secretions from other A. thaliana plants that are kin or strangers; however, little knowledge has been gained as to the physiological processes involved in these plant-plant interactions. Therefore, we examined the root transcriptome of A. thaliana plants exposed to stranger vs. kin secretions to determine genes involved in these processes. We conducted a whole transcriptome analysis on root tissues and categorized genes with significant changes in expression. Genes from four categories of interest based on significant changes in expression were identified as aTP/GST transporter, auxin/auxin related, secondary metabolite and pathogen response genes. Multiple genes in each category were tested and results indicated that pathogen response genes were involved in the kin recognition response. Plants were then infected with Pseudomonas syringe pv. Tomato Dc3000 to further examine the role of these genes in plants exposed to own, kin and stranger secretions in pathogen resistance. This study concluded that multiple physiological pathways are involved in the kin recognition. The possible implication of this study opens up a new dialog in terms of how plant-plant interactions change under a biotic stress. Key words: kin recognition, root exudates, transcriptome, Arabidopsis into the soil) from another plant ...

Belowground neighbor perception in Arabidopsis thaliana studied by transcriptome analysis: roots of Hieracium pilosella cause biotic stress

“…These analyses included the detection of significantly regulated functional categories as well as a signature analysis for similarity with a broad variety of microarrays that cover the impact both of biotic and abiotic environmental factors. In addition, our data allows for comparisons of differentially expressed genes to those found in previous studies on similar topics (Broz et al, 2008; Biedrzycki et al, 2011; Masclaux et al, 2012). …”

Kin recognition is a nutrient-dependent inducible phenomenon

“…For example, differential gene expression in response to the presence of Kin or Stranger plants has previously been observed in A. thaliana. 16 In particular, genes associated with pathogen resistance and secondary metabolite production were influenced by this phenomenon. KR can also impact the formation of symbiotic associations as observed in studies with Ambrosia artemisiifolia which establish more robust networks with sibling plants than strangers.…”

“…As genes associated with pathogen resistance are differentially regulated during such interactions it further suggests that research into KR may impact our understanding of how host-pathogen interactions are regulated under nutrient limiting conditions in the presence of multiple plants, approximating real world conditions more accurately than the isolated inoculations of lone plants. 16 The study of the molecular elements underpinning these processes also refines our understanding of the forces at work under the limited resources which drive succession and maintenance in plant communities.…”

“…1). 10,[16][17][18] In Arabidopsis thaliana and many other plants KR manifests by a significant reduction in the number of observed lateral roots when samples are grown with plants of the same accession (Kin) versus different ones (Stranger). [11][12][13][14][15] Sodium orthovanadate (Na 3 VO 4 ), a generic ABC-transport inhibitor, which blocks the release and/or uptake of root exudates, eliminated the increased lateral root number observed during KR studies with different accessions of A. thaliana.…”

“…In particular, the ability of plants to distinguish between members of the same or different accessions, the phenomenon of kin recognition (KR), has been well characterized. [8][9][10][11][12][13][14][15][16] Plants are generally thought to be incapable of processing complex visual or auditory cues, such as plumage or song, suggesting these sensory input channels are unavailable for KR. However cryptochrome-mediated KR has been observed in model organisms such as A. thaliana.…”