In this review, a summary is given of current knowledge of the regulation and function of RAV genes in diverse plant species, paying particular attention to their roles in the control of flowering in arabidopsis. TEM1 and TEM2 delay flowering by repressing the production of two florigenic molecules, FLOWERING LOCUS T (FT) and gibberellins. In this way, TEM1 and TEM2 prevent precocious flowering and postpone floral induction until the plant has accumulated enough reserves or has reached a growth stage that ensures survival of the progeny. Recent results indicate that TEM1 and TEM2 are regulated by genes acting in several flowering pathways, suggesting that TEMs may integrate information from diverse pathways. However, flowering is not the only process controlled by RAV proteins. Family members are involved in other aspects of plant development, such as bud outgrowth in trees and leaf senescence, and possibly in general growth regulation. In addition, they respond to pathogen infections and abiotic stresses, including cold, dehydration, high salinity and osmotic stress.

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MicroRNAs (miRNAs) are key regulators of numerous genes in many eukaryotes. Some plant miRNAs are involved in developmental and physiological processes that require intercellular or inter-organ signaling. Movement of other small RNAs within plants has been established. Recent findings also demonstrate intercellular signaling by miRNAs and strongly support that a subset of these regulatory molecules move from one cell to another or over long distances. Phloem exudates contain diverse miRNAs and at least two of them, involved in responses to nutrient availability, are transmitted through grafts, indicating long-distance movement. Two miRNAs that regulate developmental processes are present in cells outside their domains of expression. Several results strongly support that one of them moves from cell to cell. Research on a mutant affected in plasmodesmata trafficking indicates that these intercellular channels are required for transmission of miRNA activity to adjacent cells. Moreover, ARGONAUTE proteins might be involved in the regulation of miRNA trafficking. Hypothesis on the features and mechanisms that may determine miRNA mobility are presented. Future challenges include identifying other mobile miRNAs; demonstrating that miRNA movement is required for non-cell autonomous action; and characterizing the mechanisms of translocation and genetic pathways that regulate miRNA movement.

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A key strategy in the European Union’s ambition to establish an ‘Energy Union’ that is not just clean, but also fair, consists of empowering citizens to actively interact with the energy market as self-consumers or prosumers. Although renewable energy sources (RES) prosumerism has been growing for at least a decade, two new EU directives are intended to legitimise and facilitate its expansion. However, little is known about the full range of prosumers against which to measure policy effectiveness. We carried out a documentary study and an online survey in nine EU countries to shed light on the demographics, use of technology, organisation, financing, and motivation as well as perceived hindering and facilitating factors for collective prosumers. We identified several internal and external obstacles to the successful mainstreaming of RES prosumerism, among them a mismatch of policies with the needs of different RES prosumer types, potential organisational weaknesses as well as slow progress in essential reforms such as decentralising energy infrastructures. Our baseline results offer recommendations for the transposition of EU directives into national legislations and suggest avenues for future research in the fields of social, governance, policy, technology, and business models.