Noncoding RNAs have emerged as major components of the eukaryotic transcriptome. Genome-wide analyses revealed the existence of thousands of long noncoding RNAs (lncRNAs) in crops and model plant species. Plant lncRNAs are involved in a wide range of regulatory mechanisms impacting on gene expression, including chromatin remodeling, modulation of alternative splicing, fine-tuning of miRNA activity, and the control of mRNA translation or accumulation (Ariel et al., 2015).

In the model plant Arabidopsis thaliana, the Ariel lab has shown that the APOLO (AUXIN REGULATED PROMOTER LOOP RNA) was implicated in epigenetic and chromatin conformation dynamics. APOLO regulates the transcriptional activity of its neighboring gene PID by modulating the local 3D chromatin conformation (Ariel et al., 2014), and a plethora of target genes across the Arabidopsis genome, by sequence complementarity and DNA-RNA duplex (R-loop) formation (Ariel et al., 2020).

The Ariel lab also showed that APOLO regulates the response to low temperatures by interacting with the transcription factor WRKY42 (Moison et al., 2021 and Martínez-Pacheco et al., 2021). More recently, APOLO was also linked to the morphogenic response of the plant to warmth. Strikingly, the role of APOLO was mimicked by the human lncRNA UPAT when expressed in Arabidopsis. APOLO and UPAT interact with homolog protein partners, hinting at common lncRNA integrated epigenetic machineries across kingdoms (Fonouni-Farde et al., 2022). In 2023, The Ariel lab demonstrated that the lncRNA can be applied as an exogenous epigenetically active molecule to modulate hormone homeostasis and the response of the plant to the environment (Mammarella et al., 2023).

We find the biology of APOLO fascinating and we’ve decided to name our company after it!