Nucleo-cytoplasmic Partitioning of ARF Proteins Controls Auxin Responses in Arabidopsis thaliana

Abstract

Highlights d Condensation of transcription factors to attenuate hormone response d Mechanism for nucleo-cytoplasmic partitioning of transcription factors

Regulation of auxin transcriptional responses

“…). Interestingly, recent work has found that some activating ARF proteins form biomolecular condensates in a tissue specific manner within the plant …”

“…). Indeed, both the PB1 domain and intrinsically‐disordered MR contribute to ARF condensate formation in planta …”

“…ARF condensates are found in the cytoplasm of cells with attenuated auxin responsiveness, thus ARF condensation likely acts to sequester these transcription factors away from the nucleus to prevent activity. In line with this, disruption of ARF condensate formation leads to massive changes in gene transcription and morphological defects consistent with elevated auxin responses . Thus, ARF nucleo‐cytoplasmic partitioning and ARF condensate formation are another layer to regulate auxin response.…”

“…65). 87 Analysis of ARF protein sequences using a disordered prediction algorithm revealed a high degree of disorder in the MR of activator ARF proteins, whereas class B/C ARF proteins do not display strong predicted disorder (reviewed in Ref. 65).…”

“…Interestingly, recent work has found that some activating ARF proteins form biomolecular condensates in a tissue specific manner within the plant. 87 A common feature of molecules that form biomolecular condensates is the presence of multiple elements that can regulate intra-or inter-molecular interactions to generate the multivalency needed to drive phase separation. [111][112][113][114] Both modular protein interaction domains and IDRs play roles in proteins that form biomolecular condensates, as these regions allow for protein assembly into large oligomers or polymers and decrease the solubility of molecules to promote phase separation (reviewed in Ref.…”