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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.07.042 Byline: Ken-ichiro Hibara (a), Mari Obara (a), Emi Hayashida (a), Masashi Abe (a), Tsutomu Ishimaru (a), Hikaru Satoh (b), Jun-ichi Itoh (a), Yasuo Nagato (a) Keywords: ADAXIALIZED LEAF1 (ADL1); Phytocalpain; Adaxial-abaxial axis; Embryo development; Aleurone layer; Epidermis specification Abstract: The adaxial-abaxial axis in leaf primordia is thought to be established first and is necessary for the expansion of the leaf lamina along the mediolateral axis. To understand axis information in leaf development, we isolated the adaxialized leaf1 (adl1) mutant in rice, which forms abaxially rolled leaves. adl1 leaves are covered with bulliform-like cells, which are normally distributed only on the adaxial surface. An adl1 double mutant with the adaxially snowy leaf mutant, which has albino cells that specifically appear in the abaxial mesophyll tissue, indicated that adl1 leaves show adaxialization in both epidermal and mesophyll tissues. The expression of HD-ZIPIII genes in adl1 mutant increased in mature leaves, but not in the young primordia or the SAM. This indicated that ADL1 may not be directly involved in determining initial leaf polarity, but rather is associated with the maintenance of axis information. ADL1 encodes a plant-specific calpain-like cysteine proteinase orthologous to maize DEFECTIVE KERNEL1. Furthermore, we identified intermediate and strong alleles of the adl1 mutant that generate shootless embryos and globular-arrested embryos with aleurone layer loss, respectively. We propose that ADL1 plays an important role in pattern formation of the leaf and embryo by promoting proper epidermal development. Author Affiliation: (a) Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan (b) Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan Article History: Received 23 March 2009; Revised 9 July 2009; Accepted 20 July 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2008.04.040 Byline: Masashi Abe (a), Hideaki Kuroshita (a), Masaaki Umeda (b), Jun-Ichi Itoh (a), Yasuo Nagato (a) Keywords: Flattened shoot meristem; Rice; Apical meristem; CAF-1; Cell cycle; Fasciata1 Abstract: We isolated flattened shoot meristem (fsm) mutants in rice that showed defective seedling growth and died in the vegetative phase. Since most fsm plants had flat and small shoot apical meristems (SAMs), we suggest that FSM is required for proper SAM maintenance. FSM encodes a putative ortholog of Arabidopsis FASCIATA1 (FAS1) that corresponds to the p150 subunit of chromatin assembly factor-1 (CAF-1). FSM is expressed patchily in tissues with actively dividing cells, suggesting a tight association of FSM with specific cell-cycle phases. Double-target in situ hybridization counterstained with cell-cycle marker genes revealed that FSM is expressed mainly in the G.sub.1 phase. In fsm, expressions of the two marker genes representing S- and G.sub.2- to M-phases were enhanced in SAM, despite a reduced number of cells in SAM, suggesting that S- and G.sub.2-phases are prolonged in fsm. In addition, developmental events in fsm leaves took place at the proper time, indicating that the temporal regulation of development occurs independently of the cell-cycle period. In contrast to the fasciated phenotype of Arabidopsis fas1, fsm showed size reduction of SAM. The opposite phenotypes between fsm and fas1 indicate that the SAM maintenance is regulated differently between rice and Arabidopsis. Author Affiliation: (a) Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan (b) Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan Article History: Received 20 December 2007; Revised 24 April 2008; Accepted 30 April 2008

Abstract: A kinetic method for the determination of cysteine on flow injection system is described. Cysteine was found as a catalyst for the complexation reaction of Cu(II) with an ultra sensitive colorimetric reagent of 5,10,15,20-tetrakis (4-N-trimethylammino-phenyl) porphyrin (TTMAPP) (ɛ = 4.8×105 cm−1 M−1 at 433nm), which was used as the indicator reaction in this paper. Soret band of either the porphyrin or the produced complex (ɛ = 4.6×105 cm−1 M−1 at 411nm) can be used for detection. The continuous flow injection system greatly enhanced the analytic precision and efficiency of the kinetic method, giving a relative standard deviation of 0.73% for a 0.1μgml−1 cysteine with 10 injections at a throughput of 30h−1. The detection limits (3S/N) in this case was 15ngml−1 and the working dynamic range was over 25ngml−1 to 1μgml−1. Sugars, organic acids and amino acids that are possible in coexistence with cysteine could be tolerated at high concentrations. This method was critically compared with the Ellman''s reagent in the determinations of cysteine contents of three pharmaceutical injections for hepatic diseases and one permanent wave agent and showed better applicability in the respect of matrix interferences. [Copyright &y& Elsevier]

Abstract: A novel indirect substitution spectrophotometric methodology using porphyrin is developed for the determination of some metals that do not react with porphyrin directly. The methodology is concerned with a multistep reaction system, which consists of 3 complexation reactions that occur in a sequence of EDTA with metal, EDTA with Cu(II) and porphyrin with Cu(II). The complexation reaction of Cu(II) with a cationic porphyrin, meso-tetrakis (4-N-trimethylaminophenyl)-porphine (ttmapp), which has a high molar absorptivity about 5×105 lmol−1 cm−1, serves for spectrophotometric detection. This methodology was verified through individual determinations of 14 species of lanthanides following a batchwise procedure, which was further developed to an automatic procedure on a HPLC post-column flow injection system for simultaneous analysis of the lanthanides. Compared with the conventional post-column derivatization method using 4-(2-pyridylazo) resorcinol (PAR), the analytical sensitivity was greatly improved in this method and the results also showed good linearity. [Copyright &y& Elsevier]

Abstract: Some decapod crustaceans release larvae from estuarine or coastal shores to coastal oceans. Decapodids (last-stage larvae) return home, settle, and metamorphose into juveniles I, which go through further instars. Several morphological characters degenerate or develop in response to lifestyle transitions. Using a burrow-dwelling callianassid shrimp, Nihonotrypaea harmandi, inhabiting an intertidal sandflat in a coastal boundary layer adjacent to coastal ocean, this study described morphological changes and drew inferences about states and processes in its early life history. Decapodid and juveniles were differentiated by linea thalassinica on carapace. In the laboratory, the decapodid stage lasted 3–6d. Given choice between sandy sediments from coastal ocean bed and adult habitat, decapodids exhibited no preference, suggesting broad receptiveness. The shortest durations of the juvenile-I, -II, and -III were estimated at 6d each. Starved decapodids normally metamorphosed into juveniles I, showing secondary lecithotrophy. The non-feeding state could be extended through the juvenile I (and possibly juvenile II), where the mean total lengths of shrimps reared in groups with food (diatoms) remained about 4.6mm. Post-settlement decapodids reared individually resumed feeding. The rostrum lengths in decapodids were ≥0.36mm on the initial two dates (Days 0 and 1), after which the mean values rapidly reduced to 0.30–0.36mm on Day 2 and below 0.30mm thereafter. The pereiopod exopods disappeared through the decapodid stage from four pairs to almost zero by Day 4. In the coastal ocean, no juveniles occurred, and almost all decapodids had rostrum lengths ≥0.30mm and 3 or 4 pereiopod exopods, suggesting their pre-settlement state. Of the smallest shrimps collected on the sandflat for their subsequent rearing there, 74% were estimated to be Day-0 or -1 decapodids based on their rostrum lengths. This and the laboratory experimental results suggest (1) the acquisition of competence for settlement by newly-metamorphosed decapodids while in the coastal ocean, which was nevertheless realized there and (2) their rapid transport by flood tidal currents from coastal ocean to sandflat. The newly-settled decapodids grew steadily at 0.2mmd−1 in total length. The reared juveniles reached the smallest adult size in 80d. The uropod expod changed from elliptical to sub-circular in shape markedly around the termination of the juvenile II or III, suggesting the acquisition of ventilating function for benthic life. Overall, the post-settlement shrimps can be staged by total-length ranges as 4–5.5mm for decapodids, 5.5–10mm for juveniles, and 10–20mm for sub-adults. [Copyright &y& Elsevier]