Nobuyoshi Mochizuki

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A plastid-derived signal plays an important role in the coordinated expression of both nuclear- and chloroplast-localized genes that encode photosynthesis-related proteins. Arabidopsis GUN (genomes uncoupled) loci have been identified as components of plastid-to-nucleus signal transduction. Unlike wild-type plants, gun mutants have nuclear Lhcb1 expression(More)
The plastid plays a vital role in various cellular activities within plant cells including photosynthesis and other metabolic pathways. It is believed that the functional status of the plastid is somehow monitored by the nucleus to optimize the expression of genes encoding plastid proteins. The currently dominant model for plastid-derived signaling(More)
Contraction and relaxation of smooth muscle are regulated by myosin light-chain kinase and myosin phosphatase through phosphorylation and dephosphorylation of myosin light chains. Cyclic guanosine monophosphate (cGMP)-dependent protein kinase Ialpha (cGKIalpha) mediates physiologic relaxation of vascular smooth muscle in response to nitric oxide and cGMP.(More)
Phytochrome is a ubiquitous photoreceptor of plants and is encoded by a small multigene family. We have shown recently that a functional nuclear localization signal may reside within the COOH-terminal region of a major member of the family, phytochrome B (phyB) (Sakamoto, K., and A. Nagatani. 1996. Plant J. 10:859-868). In the present study, a fusion(More)
A plant modulates its developmental processes in response to light by several informational photoreceptors such as phytochrome. Phytochrome is a dimeric chromoprotein which regulates various aspects of plant development from seed germination to flowering. Upon absorption of red light, phytochrome translocates from the cytoplasm to the nucleus, and regulates(More)
Phototropins 1 and 2 (phot1 and phot2) function as blue light (BL) photoreceptors for phototropism, chloroplast relocation, stomatal opening and leaf flattening in Arabidopsis thaliana. Phototropin consists of two functional domains, the N-terminal photosensory domain and the C-terminal Ser/Thr kinase domain. However, little is known about the signal(More)
Lhcb and other nuclear genes for chloroplastic proteins are regulated by several signals. Among them, light and retrograde signals from the plastid itself appear to act through closely related mechanisms. To investigate this interaction, we analysed an Arabidopsis mutant, hy1, deficient in plastidic heme oxygenase. hy1 is defective in phytochrome(More)
Phototropins (phot1 and phot2, formerly designated nph1 and npl1) are blue-light receptors that mediate phototropism, blue light-induced chloroplast relocation, and blue light-induced stomatal opening in Arabidopsis. Phototropins contain two light, oxygen, or voltage (LOV) domains at their N termini (LOV1 and LOV2), each a binding site for the chromophore(More)
The phytochromes (phyA to phyE) are a major plant photoreceptor family that regulate a diversity of developmental processes in response to light. The N-terminal 651-amino acid domain of phyB (N651), which binds an open tetrapyrrole chromophore, acts to perceive and transduce regulatory light signals in the cell nucleus. The N651 domain comprises several(More)
Tetrapyrroles such as chlorophyll and heme are co-factors for essential proteins involved in a wide variety of crucial cellular functions. Nearly 2% of the proteins encoded by the Arabidopsis thaliana genome are thought to bind tetrapyrroles, demonstrating their central role in plant metabolism. Although the enzymes required for tetrapyrrole biosynthesis(More)