Transcriptional repressor (PubMed:23888064, PubMed:24806884). Direct regulator of the transcription of peroxidase (Prxs) and reactive oxygen species (ROS)-related genes via the recognition of 5'-ATCACA-3' motif (PubMed:24806884). Binds to 5'-TATCCA-3' motif (TA box) and represses the activity of corresponding promoters (e.g. sugar response genes) (PubMed:25920996). Regulates hypocotyl elongation in response to darkness by enhancing auxin accumulation in a phytochrome-interacting factor (PIF) proteins-dependent manner. Promotes lateral roots formation (PubMed:23888064). Promotes cell expansion during leaves development via the modulation of cell wall-located Prxs (PubMed:24806884). Plays a critical role in developmentally regulated and dark-induced onset of leaf senescence by repressing the transcription of several genes involved in chloroplast function and responses to light and auxin. Promotes responses to auxin, abscisic acid (ABA), and ethylene (PubMed:25920996). Expressed ubiquitously, except in hypocotyls, root tips and lateral root primordia. Accumulates during leaf expansion. First observed at the tip of the leaves 12 days after sowing (DAS). At 14 DAS, expressed throughout the leaf blade to fade out thereafter in a basipetal manner. In mature leaves, detected in vascular tissue, especially in companion cells (PubMed:24806884). Accumulates to higher levels in old rosette leaves than in young rosette and cauline leaves (PubMed:25920996). Slightly induced by CdCl(2) (PubMed:16463103). Accumulates in the dark (PubMed:23888064, PubMed:25920996). Diurnal expression pattern with maximal levels in the morning (at protein level). Specifically induced during leaf expansion (PubMed:24806884). Expressed in old and dark-treated leaves (PubMed:25920996). Contains a R/KLFGV repression motif, which may be involved in the activity of transcriptional repression. Defects in root growth. No visible hypocotyl phenotypes. Increased sensitivity to the gibberellic acid (GA) biosynthesis inhibitor paclobutrazol (PAC) and auxin (IAA) that inhibit hypocotyl elongation (PubMed:23888064). Reduced leaf size due to impaired cell expansion associated with an enhanced expression of peroxidase (Prxs) genes. This phenotype is reversed by SHAM treatment, a peroxidase inhibitor. Increased accumulation of H(2)O(2) (PubMed:24806884). Delayed senescence. Enhanced auxin-responsive gene expression (PubMed:25920996). 'Kuoda' means 'enlarge' or 'expand' in Chinese.