Srdx rabidopsis4/29/2023 Another wound-inducible AP2/ERF protein ETHYLENE RESPONSE FACTOR 115 (ERF115), acting upstream of WIND1, is required for reformation of root stem cells and regeneration of root meristems after injury (Heyman et al., 2013, 2016 Marhava et al., 2019 Zhou et al., 2019). Several other AP2/ERF family transcription factors are also implicated in the control of regeneration since PLETHORA3 (PLT3), PLT5 and PLT7, are critical for wound-induced callus formation and pluripotency acquisition under CIM/SIM condition (Kareem et al., 2015 Ikeuchi et al., 2017, 2020). At the cellular level, WIND1 promotes the acquisition of regenerative competence since ectopic overexpression of WIND1 can bypass wounding and early incubation steps on auxin-rich callus inducing medium (CIM), which are the prerequisite for shoot regeneration on cytokinin-rich shoot inducing medium (SIM) (Valvekens et al., 1988 Iwase et al., 2015). WIND induction, in addition, leads to somatic embryogenesis on phytohormone-free medium (Ikeuchi et al., 2013), implying that WIND1 can drive multiple developmental pathways to promote regeneration. WIND1 also promotes shoot regeneration via direct activation of another AP2/ERF transcription factor ENHANCER OF SHOOT REGENERATION 1 ( ESR1) (Iwase et al., 2017, 2018). We previously reported that an APETALA2/ETHYLANE RESPONSE FACTOR (AP2/ERF) transcription factor WOUND INDUCED DEDIFFERENTIATION 1 (WIND1) and its close homologs, WIND2, WIND3 and WIND4, promote wound-induced callus formation through activating the cytokinin response (Iwase et al., 2011a, b, 2013, 2015). Recent studies have indeed identified several wound-inducible transcription factors that have critical roles in regeneration (Ikeuchi et al., 2013, 2016, 2019 Xu & Huang, 2014). Given that these wound-induced events require dynamic changes in gene expression, it is likely that plants possess some transcriptional mechanisms to coordinate their progression. Although we have made considerable progress in our understanding of how plants perceive wounding signals (Toyota et al., 2018 Ikeuchi et al., 2019, 2020 Marhava et al., 2019), our knowledge on how plants initiate such a diverse array of wound-induced responses is still very limited (Bloch, 1941 Walker-Simmons et al., 1984 Savatin et al., 2014). Surface regeneration of debarked tree trunk is another well-characterized regeneration phenomenon after wounding where xylem and phloem reformation occur after callus formation (Stobbe et al., 2002). It is also known that grafted plants initially form callus at wound sites, followed by vascular bundle reformation within callus (Melnyk et al., 2015 Melnyk, 2017). Accordingly, earlier studies reported ectopic tracheary element formation in the genetic tumor of Nicotiana tabacum callus (White, 1939) and crown galls (Van Lith-Vroom et al., 1960). Importantly, wounding and callus formation is often accompanied by vascular reformation presumably to establish the route for water and nutrient transport in developing cell mass (Fukuda, 1997 Mazur et al., 2016). In plants, formation of a pluripotent cell mass, called callus, at wound sites is often a key step to regenerate new organs and develop physical and chemical barriers against pathogens (Birnbaum & Alvarado, 2008 Asahina et al., 2011 Ikeuchi et al., 2013, 2016 Melnyk, 2017). Wounding is a serious threat to the plant survival and it triggers multiple physiological responses to quickly heal and protect damaged tissues from pathogen invasion (Reymond et al., 2000 Cheong et al., 2002). This study provides deeper mechanistic insights into how plants control multiple physiological responses after wounding. These results indicate that WIND transcription factors function as key regulators of wound-induced responses by promoting dynamic transcriptional alterations.We, in addition, showed that WIND transcription factors promote tracheary element formation, vascular reconnection and resistance to Pseudomonas syringae pv. ![]() We demonstrated that WIND transcription factors induce several reprogramming genes to promote callus formation at wound sites. We observed a significant overlap between WIND1-induced genes and genes implicated in cellular reprogramming, vascular formation and pathogen response.To understand how WIND transcription factors promote downstream events, we performed time-course transcriptome analyses after WIND1 induction. We previously identified AP2/ERF transcription factors, WOUND INDUCED DEDIFFERENTIATION1 (WIND1) and its homologs, WIND2, WIND3 and WIND4, as key regulators of wound-induced cellular reprogramming in Arabidopsis.Wounding triggers de novo organogenesis, vascular reconnection and defense response but how wound stress evoke such a diverse array of physiological responses remains unknown.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |