High Temperature-Induced Expression of Rice α-Amylases in Developing Endosperm Produces Chalky Grains.

Global warming impairs grain filling in rice and reduces starch accumulation in the endosperm, leading to chalky-appearing grains, which damages their market value. We found previously that high temperature-induced expression of starch-lytic α-amylases during ripening is crucial for grain chalkiness. Because the rice genome carries at least eight functional α-amylase genes, identification of the α-amylase(s) that contribute most strongly to the production of chalky grains could accelerate efficient breeding.

Mutations in the CCD4 carotenoid cleavage dioxygenase gene of yellow-flesh peaches.

Peach trees bear either white- or yellow-flesh fruit. We found that Japanese peach cultivars have two types of mutation in a carotenoid catabolic gene, CCD4: the insertion of a retrotransposon, and a frame shift in the microsatellite sequences of the first exon. CCD4 in yellow-flesh peaches was disrupted by these mutations.

Global warming, plant paraquat resistance, and light signal transduction through nucleoside diphosphate kinase as a paradigm for increasing food supply.

Light signal transduction was studied in extracts of mycelia of the fungus Neurospora crassa, and the third internodes of dark-grown Pisum sativum cv Alaska. Both processes increased the phosphorylation of nucleoside diphosphate kinase (NDPK). NDPK may function as a carrier of reduction equivalents, as it binds NADH, thereby providing electrons to transform singlet oxygen to superoxide by catalases (CAT).

AUREOCHROME, a photoreceptor required for photomorphogenesis in stramenopiles.

A blue light (BL) receptor was discovered in stramenopile algae Vaucheria frigida (Xanthophyceae) and Fucus distichus (Phaeophyceae). Two homologs were identified in Vaucheria; each has one basic region/leucine zipper (bZIP) domain and one light-oxygen-voltage (LOV)-sensing domain. We named these chromoproteins AUREOCHROMEs (AUREO1 and AUREO2).

Identification of LOV KELCH PROTEIN2 (LKP2)-interacting factors that can recruit LKP2 to nuclear bodies.

LOV KELCH PROTEIN2 (LKP2) is an F-box protein that has been postulated to function centrally, or near to the circadian clock oscillator. As a first step to determine which proteins act as substrates of LKP2, yeast two-hybrid screening was performed using LKP2 as bait, and two interaction factors, Di19 and COL1, were isolated. The transiently expressed Di19-GUS fusion protein was localized in the nucleus of Arabidopsis petiole cells.

Arabidopsis NDK1 is a component of ROS signaling by interacting with three catalases.

Plants sense various environmental stimuli and have specific signaling pathways to respond to these cues. We focused on light responsive components and found that NDKs were phosphorylated specifically after red light irradiation in Pisum sativum [Tanaka et al. (1998) J.