Pseudo-response regulators (PRRs) or true oscillator components (TOCs)

• Published in: Plant and cell physiology Vol. 46; no. 5; pp. 677 - 685
• Main Authors: Mizuno, T.(Nagoya Univ. (Japan). Faculty of Agriculture), Nakamichi, N
• Format: Journal Article
• Language: English
• Published: Japan Oxford University Press 01.05.2005; Oxford Publishing Limited (England)
• Subjects: Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; ARABIDOPSIS THALIANA; BIOCHEMICAL PATHWAYS; BIOCHEMICAL REACTIONS; Biological clock; Biological Clocks; Biological Clocks - genetics; BIOLOGICAL RHYTHMS; CCA1; Circadiam rhythm; CIRCADIAN CLOCK-ASSOCIATED 1; circadian rhythm; Circadian Rhythm - genetics; Circadian rhythms; Flowering time; Gene Expression Regulation, Plant; Gene Expression Regulation, Plant - genetics; genetics; growth & development; histidine kinase; Hormones; LATE ELONGATED HYPOCOTYL; LHY; metabolism; MORFOGENESIS; MORPHOGENESE; MORPHOGENESIS; Photomorphogenesis; physiology; plant biochemistry; plant genetics; plant proteins; PRR; Pseudo-response regulator; REACCIONES BIOQUIMICAS; REACTION BIOCHIMIQUE; response regulator; RITMOS BIOLOGICOS; RYTHME BIOLOGIQUE; Signal Transduction; Signal Transduction - physiology; TIMING OF CAB EXPRESSION 1; TOC1; Transcription Factors; Transcriptional Activation; Transcriptional Activation - physiology; Transducers; VIA BIOQUIMICA DEL METABOLISMO; VOIE BIOCHIMIQUE DU METABOLISME
• ISSN: 0032-0781; 1471-9053
• DOI: 10.1093/pcp/pci087

In Arabidopsis thaliana, AUTHENTIC RESPONSE REGULATORS (ARRs) act as downstream components of the His-to-Asp phosphorelay (two-component) signaling pathway that is propagated primarily by the cytokinin receptor kinases, AUTHENTIC HIS-KINASES (AHK2, AHK3 and AHK4/CRE1). Thus, this bacterial type of signaling system is essential for responses to a class of hormones in plants. Interestingly, this higher plant has also evolved its own atypical (or unique) variants of two-component signal transducers, PSEUDO-ESPONSE REGULATOERS (PRRS). Several lines of recent results suggest that the functions of PRRS are closely relevant to the plant clock (oscillator) that is central to circadian rhythms, the underlying mechanisms of which have long been the subject of debate. Through an overview of recent results, the main issue addressed here is whether or not the pseudo-response regulators (PRRs) are true oscillator components (TOCs).