Common Mechanisms of Developmental Reprogramming in Plants—Lessons From Regeneration, Symbiosis, and Parasitism

Abstract

Most plants are exquisitely sensitive to their environment and adapt by reprogramming post-embryonic development. The systematic understanding of molecular mechanisms regulating developmental reprogramming has been underexplored because abiotic and biotic stimuli that lead to reprogramming of post-embryonic development vary and the outcomes are highly species-specific. In this review, we discuss the diversity and similarities of developmental reprogramming processes by summarizing recent key findings in reprogrammed development: plant regeneration, nodule organogenesis in symbiosis, and haustorial formation in parasitism. We highlight the potentially shared molecular mechanisms across the different developmental programs, especially a core network module mediated by the AUXIN RESPONSIVE FACTOR (ARF) and the LATERAL ORGAN BOUNDARIES DOMAIN (LBD) family of transcription factors. This allows us to propose a new holistic concept that will provide insights into the nature of plant development, catalyzing the fusion of subdisciplines in plant developmental biology.

Plant stem cell research is uncovering the secrets of longevity and persistent growth

“…In contrast, wounded plants are able to generate new stem cells with higher potency by reprogramming of differentiated cells with limited potency (Birnbaum and Sanchez Alvarado, 2008). At wound sites, flowering plants first activate cell division and form cell clumps called calli, which then generate stem cells for shoots or roots depending on their position within the plant body (Ichihashi et al , 2020; Ikeuchi et al , 2019). In tissue culture, these processes are often enhanced by exogenously supplied hormones, such as auxin and cytokinin.…”

“…Although many factors involved in organ development and stem cell maintenance have been shown to be associated with de novo stem cell formation, it remains unclear whether they have crucial roles in direct reprogramming of somatic cells into stem cells. The legume L. japonicus forms root nodules in response to infection by nitrogen‐fixing bacteria, which activates the cell cycle in the cortex by inducing the RWP‐RK transcription factor NODULE INCEPTION (NIN) and may trigger stem cell formation (Ferguson et al , 2019; Ichihashi et al , 2020). Gemma formation in M. polymorpha requires the MYB transcription factor GEMMA CUP‐ASSOCIATED MYB1 (GCAM1), overexpression of which generates a mass of undifferentiated cells (Yasui et al , 2019).…”

Orobanchaceae parasite–host interactions

“…Indeed, gene expression patterns in both lateral root development and haustorium development partly overlap (Yoshida et al, 2019). The key regulator may be LATERAL ORGAN BOUNDARIES DOMAIN (LBD) proteins that orchestrate auxin downstream signaling for induced development and are highly upregulated in haustorium development in several parasitic plant species (Ichihashi et al, 2018;Ichihashi et al, 2020).…”

Characterization of Transcription Regulatory Domains of OsMADS29: Identification of Proximal Auxin-Responsive Domains and a Strong Distal Negative Element

“…Each of these aspects requires a great deal of coordination between sensory mechanisms and mechanisms that control gene expression. Regulating developmental transitions requires transcribing the relevant genetic information at the right moment and spurring the correct phenotypic response ( She et al, 2013 ; Ichihashi et al, 2020 ; Borg et al, 2021 ). Chromatin is the warehouse of genetic information, and its packaging is critical for both maintaining and transcribing this data.…”