Nucleoside diphosphate kinase isoforms regulated by phytochrome A isolated from oat coleoptiles.

Abstract

Nucleoside diphosphate kinase (NDPK) (EC 2.7.4.6), the enzyme transferring the phosphate residue from ATP to nucleoside diphosphates, is localized mainly in the cytoplasm and mitochondria and in smaller amounts in cell nuclei and the microsomal fraction. Exposure of etiolated oat seedlings to red light causes an increase of the enzyme activity by about 42% in nuclear fraction, 7% in etioplastic and 14% in postetioplastic fraction. Endogenous phytochrome A, as visualized by an immunochemical method, translocates from the cytoplasm into the nucleus upon red, far-red or white light activation. Nuclei purified from oat seedlings contain two, and the postnuclear fraction four easily separated forms of NDPK. One of the nuclear isoforms (I(n)) and one isoform isolated from the postnuclear fraction (II(pn)) are activated by red light in the presence of phytochrome A purified from etiolated oat coleoptiles. Both phytochrome A-activated NDPKs purified to electrophoretic homogeneity have the same molecular mass (17-18 kDa) determined by SDS/PAGE. Both enzymes in the native form have similar molecular masses (71 and 63 kDa).

Phytochrome‐mediated regulation of plant respiration and photorespiration

“…Phytochrome-mediated release of Ca 2+ from the mitochondrial matrix may explain light depression of ATPase activity and its reversal by far-red light (Serlin, Sopory & Roux 1984). Nucleoside diphosphate kinase is another respiration-related enzyme that can be directly regulated by phytochrome (Choi et al 1999;Hetmann & Kowalczyk 2009); however, only the nuclear isoform, and possibly one etioplastic form was activated by light with no evidence of the mitochondrial isoform being involved. Although the direct regulation of mitochondrial respiration by phytochrome acting at the membrane level represents not quite well-explored mechanism, most studies deal with the regulation of expression of proteins participating in the respiratory process at gene level.…”

Proteomics Analysis of SsNsd1-Mediated Compound Appressoria Formation in Sclerotinia sclerotiorum

“…Here, we provide information concerning the analysis of the predicted functionally known proteins. Nucleoside diphosphate kinase (NDPK) (spots 1, 9, and 17) usually possesses kinase activity exerted by direct response to the G-protein signaling or indirect catalytic GDP–GTP exchange activity, which also plays a major role in the synthesis of nucleoside triphosphates [ 27 , 28 , 29 ]. The eukaryotic translation initiation factor 5A-1 (eIF5A-1; spot 18) is involved in the protein fate pathway [ 30 ], which activates the 60 s subunits combination, assists in the conformational changes of the 80 s subunits, and participates in the intracellular part; proteins associate with ribosomes cyclically during the elongation phase of the protein synthesis [ 31 ].…”

A Comparative Transcriptome Analysis Reveals Physiological Maturation Properties of Mycelia in Pleurotus tuoliensis

“…Among our DEGs, the upregulation expression of NDPK is interesting. Many studies have demonstrated that NDPK regulates various biological processes and signal transduction pathways in addition to playing a fundamental role in maintaining the cellular balance of NDP and NTP [22,23]. In Neurospora crassa , Ndpk is associated with hyphal development and photomorphogenesis [24].…”