In contrast to other cereals, typical barley cultivars have caryopses with adhering hulls at maturity, known as covered (hulled) barley. However, a few barley cultivars are a free-threshing variant called naked (hulless) barley. The covered/naked caryopsis is controlled by a single locus (nud) on chromosome arm 7HL. On the basis of positional cloning, we concluded that an ethylene response factor (ERF) family transcription factor gene controls the covered/naked caryopsis phenotype. This conclusion was validated by (i) fixation of the 17-kb deletion harboring the ERF gene among all 100 naked cultivars studied; (ii) two x-ray-induced nud alleles with a DNA lesion at a different site, each affecting the putative functional motif; and (iii) gene expression strictly localized to the testa. Available results indicate the monophyletic origin of naked barley. The Nud gene has homology to the Arabidopsis WIN1/SHN1 transcription factor gene, whose deduced function is control of a lipid biosynthesis pathway. Staining with a lipophilic dye (Sudan black B) detected a lipid layer on the pericarp epidermis only in covered barley. We infer that, in covered barley, the contact of the caryopsis surface, overlaid with lipids to the inner side of the hull, generates organ adhesion.caryopsis ͉ domestication ͉ epidermis ͉ ethylene response factor ͉ grass B arley (Hordeum vulgare L.) is the world's fourth most important cereal crop behind wheat, rice, and maize. A particular botanical feature of domesticated barley is that most cultivars have covered (hulled) caryopses in which the hull (outer lemma and inner palea) is firmly adherent to the pericarp epidermis at maturity; but a few cultivars are of a free-threshing variant called naked (hulless) barley (Fig. 1). No other Poaceae (grass) family crops show such hull-caryopsis adhesion. Both caryopsis types of barley have agronomic value and are used for different purposes. Covered barley is mainly used as an animal feed and for brewing. The hull of covered barley protects embryos from damage during mechanical harvest, and it also provides a filtration medium in separation of fermentable extract (wort) during malt processing (1). In contrast, naked barley is preferred for human food, because extensive pearling to remove the hull is unnecessary. Now that healthy effects of the soluble-fiber-rich barley products have been officially approved (2, 3), consumers' current interest in nutrition might boost the status of barley as human food.Easy processing of edible part can be a primary character of selection during domestication of a food crop (4, 5). Consequently, the naked caryopsis is considered a key domestication character in barley (5-8). The wild progenitor of barley, H. vulgare subsp. spontaneum, has covered grains. The covered grain is therefore considered adaptive in the wild: the hulls protect the caryopses from various biotic and abiotic stresses, and the awn attached to the distal end of the lemma facilitates seed dispersal and burial (9). According to archeological evidence (4)...

We reported previously (Kataoka, T., Muroi, M., Ohkuma, S., Waritani, T., Magae, J., Takatsuki /Cl؊ symport (or OH ؊ /Cl ؊ exchange, in its equivalence) across vesicular membranes. In fact, prodigiosins displayed H ؉ /Cl ؊ symport activity on liposomal membranes. First of all, they decreased the internal pH of liposomes depending on the external chloride, and raised it depending on the internal chloride when external buffer was free from chloride. Second, their effect was electroneutral and not seriously affected by the application of an inside positive membrane potential generated by K ؉ and valinomycin. Finally, they promoted the uptake of [ 36 Cl] from external buffers with concomitant intraliposomal acidification when external pH was acidic relative to liposome interior. As prodigiosins hardly inhibit the catalytic activity (ATP hydrolysis) unlike well known OH ؊ /Cl ؊ exchangers (for example, tributyltin chloride), they should provide powerful tools for the study of molecular machinery and cellular activities involving transport of protons and/or chloride.

Various types of lipid membrane-incorporated C60 with high C60 concentrations can be prepared easily in several hours using the C60 exchange method and the photocleaving activity of cationic lipid membrane-incorporated C60 was appreciably higher than that of the C60.gamma-CDx complex.

Unlike microevolutionary processes, little is known about the genetic basis of macroevolutionary processes. One of these magnificent examples is the transition from non-avian dinosaurs to birds that has created numerous evolutionary innovations such as self-powered flight and its associated wings with flight feathers. By analysing 48 bird genomes, we identified millions of avian-specific highly conserved elements (ASHCEs) that predominantly (>99%) reside in non-coding regions. Many ASHCEs show differential histone modifications that may participate in regulation of limb development. Comparative embryonic gene expression analyses across tetrapod species suggest ASHCE-associated genes have unique roles in developing avian limbs. In particular, we demonstrate how the ASHCE driven avian-specific expression of gene Sim1 driven by ASHCE may be associated with the evolution and development of flight feathers. Together, these findings demonstrate regulatory roles of ASHCEs in the creation of avian-specific traits, and further highlight the importance of cis-regulatory rewiring during macroevolutionary changes.

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We reported previously [Kataoka, Muroi, Ohkuma, Waritani, Magae, Takatsuki, Kondo, Yamasaki and Nagai (1995) FEBS Lett. 359, 53-59] that prodigiosin 25-C (one of the red pigments of the prodigiosin group produced by micro-organisms like Streptomyces and Serratia) uncoupled vacuolar H+-ATPase, inhibited vacuolar acidification and affected glycoprotein processing. In the present study we show that prodigiosin, metacycloprodigiosin and prodigiosin 25-C, all raise intralysosomal pH through inhibition of lysosomal acidification driven by vacuolar-type (V-)ATPase without inhibiting ATP hydrolysis in a dose-dependent manner with IC50 values of 30-120 pmol/mg of protein. The inhibition against lysosomal acidification was quick and reversible, showing kinetics of simple non-competitive (for ATP) inhibition. However, the prodigiosins neither raised the internal pH of isolated lysosomes nor showed ionophoric activity against H+ or K+ at concentrations where they strongly inhibited lysosomal acidification. They required Cl- for their acidification inhibitory activity even when driven in the presence of K+ and valinomycin, suggesting that their target is not anion (chloride) channel(s). In fact, the prodigiosins inhibited acidification of proteoliposomes devoid of anion channels that were reconstituted from lysosomal vacuolar-type (V-)ATPase and Escherichia coli phospholipids. However, they did not inhibit the formation of an inside-positive membrane potential driven by lysosomal V-ATPase. Instead, they caused quick reversal of acidified pH driven by lysosomal V-ATPase and, in acidic buffer, produced quick acidification of lysosomal pH, both only in the presence of Cl-. In addition, they induced swelling of liposomes and erythrocytes in iso-osmotic ammonium salt of chloride but not of gluconate, suggesting the promotion of Cl- entry by prodigiosins. These results suggest that prodigiosins facilitate the symport of H+ with Cl- (or exchange of OH- with Cl-) through lysosomal membranes, resulting in uncoupling of vacuolar H+-ATPase.

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