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Chlorophyll (chl) degradation plays a vital role during green plant growth and development, including nutrient metabolism, fruit and seed maturation, and phototoxic detoxification. STAY-GREEN (SGR) is a plant-specific regulator involved in chl degradation. Previous studies showed that SlSGR1 functioned in chl degradation and lycopene accumulation during fruit ripening of tomato (Solanum lycopersicum). However, little is known about SlSGR-LIKE (SlSGRL) gene, which is a homolog of SlSGR1. We cloned the SlSGRL gene and created transgenic tomato plants overexpressing (OE) SlSGRL. Expression analysis showed that SlSGRL was up-regulated by abscisic acid (ABA). Our data showed that SlSGRL-OE lines exhibited earlier leaf yellowing than wild-type (WT) lines under ABA treatment. Yeast two-hybrid (Y2H) assay revealed that SlSGRL interacted with pheophytin pheophorbide hydrolase (SlPPH) and light-harvesting complex a2 (SlLHCa2) to promote the chl degradation. Further analysis demonstrated that ABA-INSENSITIVE5 (SlABI5) and SlABI5-LIKE regulated SlSGRL expression by directly binding to the sequence (-611 to -582) of the SlSGRL promoter that included an ABRE cis-element. We proposed that SlSGRL, which was regulated by SlABI5/SlABI5-LIKE, mainly acted in ABA-induced chl degradation via interacting with SlPPH and SlLHCa2.

Some insect growth disruptors (IGDs), such as pyriproxyfen and halofenozide, may be used to control Leptinotarsa decemlineata. However, their mechanism of action remains elusive. Methoprene-tolerant (Met) mediates juvenile hormone (JH) signal to control numerous essential physiological processes. In the present paper, we identified a Met gene (LdMet). LdMet protein was a typical basic helix-loop-helix/Per-Arnt-Sim (bHLH-PAS) transcription factor with a bHLH domain, two PAS domains (PAS-A and PAS-B) and a region called PAS associated C terminal (PAC). Eight conserved amino acids critical for JH binding were located in PAS-B and PAC domains. The temporal expression pattern of LdMet was in accordance with the variation of circulating JH titers. Feeding of juvenoid methoprene or pyriproxyfen, or provide for JH dose-dependently stimulated the expression of LdMet. RNA interference-mediated knockdown of two JH degradation genes increased the transcription of LdMet, while silencing of a JH biosynthesis gene repressed the transcription. Conversely, ingestion of an ecdysteroid agonist halofenozide or 20-hydroxyecdysone (20E) reduced the mRNA levels of LdMet, in a dose-dependent manner, whereas knockdown of either ecdysteroidogenesis or 20E signaling genes increased the mRNA accumulation. Providing that the expression of LdMet can be disturbed by methoprene, pyriproxyfen and halofenozide, LdMet may be a potential target of these IGDs in L. decemlineata larvae.

In the tobacco hornworm Manduca sexta, juvenile hormone (JH) is critical for the control of species-specific size. However, whether the basic helix-loop-helix/Per-Arnt-Sim domain receptor methoprene-tolerant (Met) is involved remains unconfirmed. In the present paper, we found that RNA interference (RNAi)-aided knockdown of Met gene (LdMet) lowered the larval and pupal fresh weights and shortened the larval development period in the Colorado potato beetle Leptinotarsa decemlineata. Dietary introduction of JH into the LdMet RNAi larvae rescued neither the decreased weights nor the reduced development phase, even though JH ingestion by control larvae extended developmental time and caused large pupae. Moreover, the transcript levels of five genes involved in prothoracicotropic hormone and cap 'n' collar isoform C/Kelch-like ECH associated protein 1 pathways were upregulated in the LdMet silenced larvae. Ecdysteroidogenesis was thereby activated; 20-hydroxyecdysone (20E) titer was increased; and 20E signaling pathway was elicited in the LdMet RNAi larvae. Therefore, JH, acting through its receptor Met, inhibits PTTH production and release before the attainment of critical weight. Once the critical weight is reached, JH production and release are averted; and the hemolymph JH is removed. The elimination of JH allows the brain to release PTTH. PTTH subsequently stimulates ecdysteroid biosynthesis and release to start larval-pupal transition in L. decemlineata.

It is challenging to purify wastewater containing heavy metals at low concentrations. Forward osmosis (FO) is promising to remove most of contaminants from wastewater. However, the lack of suitable membranes disables FO to achieve its full potential. Here we designed positively charged PA-Fe-H2O and PA-Fe-Bet membranes for efficient chromium (CrO42-) removal through micellar-enhanced FO (MEFO) separation. These membranes were developed by functionalizing the ready-made polyamine (PA) membrane via eco-friendly complexation between Fe3+ and carboxyl groups of the PA layer and/or betaine (Bet). A Fe3+-bridged hydration or quaternary ammonium layer was formed which imbued the membrane with desirable properties for FO separation. The water permeability of the PA-Fe-H2O and PA-Fe-Bet membranes was increased by 92% and 142%, respectively, compared to that of the PA membrane when 0.5 M MgCl2 as the draw solution. The PA-Fe-Bet membrane greatly improved CrO42- removal efficiency by increasing the water flux from 6.2 to 12.0 LMH along with complete CrO42- retention in the cetylpyridinium chloride (CPC) facilitated MEFO process. Moreover, this membrane exhibited enhanced antifouling properties when exposed to CPC solutions. The environmentally benign synthesis approach, high CrO42- removal efficiency and fouling resistance of the PA-Fe-Bet membrane demonstrate its potential for contaminants removal.

Trehalose is proposed to serve multiple physiological roles in insects. However, its importance remains largely unconfirmed. In the present paper, we knocked down either a trehalose biosynthesis gene (trehalose-6-phosphate synthase, LdTPS) or each of three degradation genes (soluble trehalases LdTRE1a, LdTRE1b or membrane-bound LdTRE2) in Leptinotarsa decemlineata by RNA interference (RNAi). Knockdown of LdTPS decreased trehalose content and caused larval and pupal lethality. The LdTPS RNAi survivors consumed a greater amount of foliage, obtained a heavier body mass, accumulated more glycogen, lipid and proline, and had a smaller amount of chitin compared with the controls. Ingestion of trehalose but not glucose rescued the food consumption increase and larval mass rise, increased survivorship, and recovered glycogen, lipid and chitin to the normal levels. In contrast, silencing of LdTRE1a increased trehalose content and resulted in larval and pupal lethality. The surviving LdTRE1a RNAi hypomorphs fed a smaller quantity of food, had a lighter body weight, depleted lipid and several glucogenic amino acids, and contained a smaller amount of chitin. Neither trehalose nor glucose ingestion rescued these LdTRE1a RNAi defects. Silencing of LdTRE1b caused little effects. Knockdown of LdTRE2 caused larval death, increased trehalose contents in several tissues and diminished glycogen in the brain-corpora cardiaca-corpora allata complex (BCC). Feeding glucose but not trehalose partially rescued the high mortality rate and recovered glycogen content in the BCC. It seems that trehalose is involved in feeding regulation, sugar absorption, brain energy supply and chitin biosynthesis in L. decemlineata larvae.

The NAC proteins are the largest transcription factors in plants. The functions of NACs are various and we focus on their roles in response to abiotic stress here. In our study, a typical NAC gene (SlNAM1) is isolated from tomato and its product is located in the nucleus. It also has a transcriptional activity region situated in C-terminal. The expression levels of SlNAM1 in tomato were induced by 4°C, PEG, NaCl, abscisic acid (ABA) and methyl jasmonate (MeJA) treatments. The function of SlNAM1 in response to chilling stress has been investigated. SlNAM1 overexpression in tobacco exhibited higher germination rates, minor wilting, and higher photosynthetic rates (Pn) under chilling stress. Meanwhile, overexpression of SlNAM1 improved the osmolytes contents and reduced the H2O2 and O2•- contents under low temperature, which contribute to alleviating the oxidative damage of cell membrane after chilling stress. Moreover, the transcripts of NtDREB1, NtP5CS, and NtERD10s were higher in transgenic tobacco, and those increased expressions may confer higher chilling tolerance of transgenic plants. These results indicated that overexpression of SlNAM1 could improve chilling stress tolerance of transgenic tobacco.

In Drosophila melanogaster prothoracic gland (PG) cells, Torso mediates prothoracicotropic hormone (PTTH)-triggered mitogen activated protein kinase (MAPK) pathway (consisting of four core components Ras, Raf, MEK and ERK) to stimulate ecdysteroidogenesis. In this study, LdTorso, LdRas, LdRaf and LdERK were cloned in Leptinotarsa decemlineata. The four genes were highly or moderately expressed in the larval prothoracic glands. At the first- to third-instar stages, their expression levels were higher just before and right after the molt, and were lower in the mid instars. At the fourth-instar stage, their transcript levels were higher before prepupal stage. RNA interference-mediated knockdown of LdTorso delayed larval development, increased pupal weight, and impaired pupation and adult emergence. Moreover, knockdown of LdTorso decreased the mRNA levels of LdRas, LdRaf and LdERK, repressed the transcription of two ecdysteroidogenesis genes (LdPHM and LdDIB), lowered 20E titer, and downregulated the expression of several 20E-response genes (LdEcR, LdUSP, LdHR3 and LdFTZ-F1). Furthermore, silencing of LdTorso induced the expression of a JH biosynthesis gene LdJHAMT, increased JH titer, and activated the transcription of a JH early-inducible gene LdKr-h1. Thus, our results suggest that Torso transduces PTTH-triggered MAPK signal to regulate ecdysteroidogenesis in the PGs in a non-drosophiline insect.

Study Objective To evaluate the safety and efficacy of a new crosslinked hyaluronan (NCH) gel in reducing postoperative adhesions. Design Randomized controlled trial (Canadian Task Force classification I). Settings Seven departments of obstetrics and gynecology in China. Patients A total of 216 women scheduled for gynecologic laparoscopic surgery for primary removal of adhesions, myomas, ovarian cysts, or endometriotic cysts. Interventions Patients were randomized to receive either NCH gel or saline with 1:1 allocation. Measurements and Main Results All patients were evaluated using a modified American Fertility Society (mAFS) scoring system for the incidence, extent, and severity of pre-existing and postoperative adhesions at the 10 anatomic sites of ovaries/tubes and at the expanded 23 or 24 anatomic sites throughout the abdominopelvic cavity by laparoscopy. A total of 215 randomized patients were treated with either saline solution (108 of 108) or NCH gel (107 of 108), composing the full analysis set (FAS), and 196 patients (94 of 108 in the saline control group and 102 of 108 in the NCH gel group) completed the entire study, composing the per protocol set (PPS). The postoperative incidence of moderate or severe adhesions evaluated at the 10 sites (the primary endpoint for efficacy) was 27.7% in the control group and 9.8% in the NCH gel group, a difference of 14.4% (95% confidence interval [CI], 2.6%–20.6%) in the PPS, and 37.0% in the control group and 14.0% in the NCH gel group, a difference of 20.0% (95% CI, 8.9%–26.8%) in the FAS. The postoperative incidence of moderate or severe adhesions evaluated at the 24 sites was also significantly lower in the NCH gel group compared with the control group (5.9% vs 14.9%; p = .036) in the PPS. Also in the PPS, the NCH gel group had significantly lower postoperative adhesion scores of severity, extent, and mAFS: 60.0%, 50.8%, and 76.9%, respectively (median scores of the 10 sites; p = .002) and 48.5%, 50.0%, and 72.2% (median scores of the 24 sites; p = .001) lower than those recorded in the control group. No serious adverse events were observed, and the safety profile of NCH gel was comparable to that of saline control. Conclusion This study demonstrates that NCH gel is safe and significantly reduces adnexal adhesion formation and global adhesion formation throughout the abdominopelvic cavity after gynecologic laparoscopic surgery.

The basic helix–loop–helix (bHLH) transcription factors possess crucial functions in cell proliferation, determination, differentiation, cell cycle maintenance and homeostasis or stress response pathways. Since a few juvenile hormone analogues such as hydroprene, methoprene and pyriproxyfen targeting a bHLH member Met are already registered for pest management, there is a potential to develop more insecticides targeting various bHLHs. The identification of bHLH members is the first step. Based on the transcriptome and the genome of the Colorado potato beetle Leptinotarsa decemlineata, the most important pest in potato, 49 bHLH members were identified. All LdbHLH members were defined by their names and families according to various phylogenetic analyses with bHLH homologues of Drosophila melanogaster, Apis mellifera, Bombyx mori and Tribolium castaneum. Among these LdbHLHs, 17, 10, 10, 1, 10 and 1 members belonged to A, B, C, D, E and F high-order groups, respectively. The results would provide useful background information for future studies on functions of bHLH proteins in the regulation of L. decemlineata development. Moreover, the bHLHs could serve as potential insecticide targets. These proteins could be used in small molecule screen, or in the development of RNAi-based pest management methods.

The R2R3-MYB protein SlAN2 has long been thought to be a positive regulator of anthocyanin accumulation. To investigate the role of SlAN2, we have previously overexpressed the gene in tomato. In this work, we analysed physiological characters of the transgenic plants during the fruit ripening. We show that fruits of transformants overexpressing SlAN2 displayed an orange colour, fast softening and elevated ethylene production. Overexpression of SlAN2 resulted in reduction of carotenoid levels via alteration of flux through the carotenoid pathway, elevated ethylene synthesis mainly via upregulation of ethylene biosynthesis genes, and early softening of fruits. We also found that the transcript level of SlRIN, an important ripening-related gene, was up-regulated in transgenic fruits. These results suggest that SlAN2 acts as an important regulator of fruit ripening.

LeAN2 is an anthocyanin-associated R2R3-MYB transcription factor, but little is known about its function in imparting thermo-tolerance to higher plants. To examine the function of LeAN2 in the regulation of heat stress in tomato, LeAN2 was isolated and transgenic tomato plants were obtained. Overexpression of LeAN2 under the control of the CaMV35S promoter in tomato induced the up-regulation of several structural genes in the anthocyanin biosynthetic pathway as well as anthocyanin accumulation in transgenic tomato plants. Transgenic tomato plants showed enhanced tolerance to heat stress by maintaining higher fresh weight (FW), net photosynthetic rate (Pn) and maximal photochemical efficiency of photosystem II (PSII) (Fv/Fm) compared with wild-type (WT) plants. Furthermore, transgenic plants showed higher non-enzymatic antioxidant activity, lower levels of reactive oxygen species (ROS), and higher contents of D1 protein than that in WT plants under heat stress. These results indicate that LeAN2 had an important function in heat stress resistance.

Juvenile hormone III (JH III) plays primary roles in regulation of metamorphosis, reproduction and diapause in Leptinotarsa decemlineata, a notorious defoliator of potato. The neurosecretory cell-borne substance(s) negatively affects the final two steps in JH biosynthesis, catalyzed respectively by an epoxidase CYP15A1 and a juvenile hormone acid methyltransferase (JHAMT). In a few insect species other than L. decemlineata, the inhibitory substance is allatostatin (AS) neuropeptide. In this study, two putative AS genes encoding LdAS-C and LdAS-B precursors were cloned. Both LdAS-C and LdAS-B were expressed in the egg, larvae, pupae and adults, and highly expressed in the brain and the gut. Dietary introduction of double-stranded RNAs (dsRNAs) targeting LdAS-C and LdAS-B successfully knocked down respective target genes. Ingestion during 3 and 6 consecutive days of dsLdAS-C significantly increased the LdJHAMT mRNA levels by 3.8 and 9.9 fold respectively. In contrast, ingestion of dsLdAS-B only slightly increased the LdJHAMT expression level by 1.1 and 1.7 fold. Moreover, after one, two and three days' ingestion of dsLdAS-C, the relative JH levels in the hemolymph of treated larvae were 2.5, 4.2 and 1.9 fold higher than those in control beetles. Furthermore, ingestion of dsLdAS-C and dsLdAS-B significantly affected larval growth and delayed larval development. Thus, we provide a line of experimental evidence in L. decemlineata to support the concept that AS-C acts as an allatostatin and inhibit JH biosynthesis.

Chilling is one of the most serious environmental stresses that disrupt the metabolic balance of cells and enhance the production of reactive oxygen species (ROS). Light harvesting complex (LHC) proteins had a function in dissipating excess excitation energy and eliminating ROS to maintain the normal physiological function of cells. A tomato (Lycopersicon esculentum) LHC antenna protein gene (LeLhcb2) was isolated. The LeLhcb2-green fluorescent protein (GFP) fusion protein was targeted to the chloroplast of Arabidopsis mesophyll protoplast. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the expression of LeLhcb2 was markedly abundant in leaves and was induced by chilling (4 °C). qRT-PCR analysis and western blot confirmed that the sense gene LeLhcb2 was transferred into tobacco genome and overexpressed. Under chilling stress, the transgenic plants showed not only better growth, higher fresh weight, chlorophyll content, but also lower malondialdehyde (MDA) accumulation and relative electrical conductivity (REC), compared with the wild type (WT). The maximal photochemical efficiency of PSII (Fv/Fm), non-photochemical quenching (NPQ) and D1 protein content were also higher in the transgenic plants. Furthermore, the relatively lower hydrogen peroxide (H2O2) and superoxide radical (O2(-)) levels in the sense plants were not considered to due to the higher activity of ascorbate peroxidase (APX) and superoxide dismutase (SOD). These results suggested that the overexpression of LeLhcb2 had a key function in alleviating photo-oxidation of PSII and enhanced transgenic tobacco tolerance to chilling stress.

ICE1 (inducer of CBF expression 1), a MYC-type bHLH transcription factor, is an important activator of CBF3/DREB1A for regulating cold signaling and stress tolerance. In this study, we isolated the novel ICE1-like gene SlICE1a from tomato which contains the conserved bHLH domain, an S-rich motif, and ACT-domain. It is localized in the nucleus and harbors transcription-activating activity in the N-terminal. In addition, the SlICE1a transcript is slightly upregulated by cold stress, salt stress, and osmotic stress. SlICE1a overexpression in tobacco enhances the induction of CBF/DREB and their target genes, consequently increasing the levels of proline, soluble sugars, and late embryogenesis abundant (LEA) proteins, and enhancing tolerance to cold stress, osmotic stress, and salt stress. SlICE1a functions in abiotic stress responses by regulating the expression of stress-tolerant genes, and is thus beneficial for crop improvement.

Chilling is one of the most serious environmental stresses that disrupt the metabolic balance of cells and enhance the production of reactive oxygen species (ROS). Lutein plays important roles in dissipating excess excitation energy and eliminating ROS to maintain the normal physiological function of cells. A tomato carotenoid epsilon-ring hydroxylase gene (LeLUT1) was isolated, and the LeLUT1-GFP fusion protein was localized in the chloroplast of Arabidopsis mesophyll protoplast. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the expression of LeLUT1 was the highest in the leaves and was down-regulated by various abiotic stresses in tomato. The transgenic tobacco plants overexpressing LeLUT1 had higher lutein content, which was decreased in cold condition. Under chilling stress, the non-photochemical quenching (NPQ) values were higher in the transgenic plants than in the wild type (WT) plants. Compared with the WT plants, the transgenic plants showed lower levels of hydrogen peroxide (H2O2), superoxide radical (O2(·-)), relative electrical conductivity, and malondialdehyde content (MDA), and relatively higher values of maximal photochemical efficiency of photosystem II (Fv/Fm), oxidizable P700 of PSI, and net photosynthetic rate (Pn). Therefore, the transgenic seedlings were less suppressed in growth and lost less cotyledon chlorophyll than the WT seedlings. These results suggested that the overexpression of LeLUT1 had a key function in alleviating photoinhibition and photooxidation, and decreased the sensitivity of photosynthesis to chilling stress.

Uninterrupted wide range operations are salient features of the process industries. Characteristics including nonlinearity, time-delay, and inertia, of industrial control loops are always significantly changed with the working conditions. To qualify the nonlinear degree, a nonlinearity measure based on the minimum variance lower bound ratio is presented in this paper. This measure belongs to the data-driven class, and can be applied to Hammerstein structure, Wiener structure and Wiener–Hammerstein structure, whether the controller is linear or nonlinear. The effectiveness and consistency of this measure are illustrated through five simulation tests. An industrial case in the fossil fuel power generation process is studied to confirm the practicability of the proposed measure.

Photosynthesis is a well-established source of reactive oxygen species (ROS) in plants particularly under chilling stress. Ascorbate peroxidase (APXs) plays an important role in the anti-oxidant system by utilizing AsA as specific electron donor to reduce H 2 O 2 to water. In order to investigate the possible mechanisms of ascorbate peroxidsae (APX) in photoprotection under chilling stress, a tomato ( Lycopersicon esculentum Mill.) thylakoidal ascorbate peroxidase gene ( LetAPX ) was isolated and antisense transgenic tomato plants were produced. Under chilling stress, transgenic plants accumulated more H 2 O 2 , and showed higher levels of ion leakage and malondialdehyde (MDA), lower net photosynthetic rate (Pn), lower maximal photochemical efficiency of PSII (Fv/Fm) and less content of D1 protein compared with wild type (WT) plants. On the other hand, after chilling stress, transgenic plants showed higher reduced ascorbate (AsA) and activities of catalase (CAT) and superoxide dismutase (SOD) than those in WT plants, and the expression of several known stress-responsive and antioxidative genes was also higher at the end of chilling treatment. These results suggested that the suppression of LetAPX gene induced compensatory anti-oxidant mechanisms in tomato, and inactivation of tAPX may have a regulatory role in facilitating redox signaling pathways under chilling stress. Furthermore, transient increases in ROS levels also have a vital role in stress signaling and thereby in the survival of plants under chilling conditions.

Photosynthesis provides a strong reducing power and a high risk for generation of reactive oxygen species (ROS) particularly under chilling stress. Ascorbate peroxidases (APXs) reduce H(2)O(2) to water and play an important role in the antioxidant system of plants. Though thylakoid ascorbate peroxidase (tAPX) has been thought to be key regulator of intracellular levels of H(2)O(2), its physiological significance in the response to chilling stress is still under discussion. To study the contribution of tAPX to the ROS scavenging, a tomato thylakoidal ascorbate peroxidase gene (LetAPX) was isolated and transgenic tomatoes were obtained. The LetAPX-GFP fusion protein was targeted to chloroplast in Arabidopsis mesophyll protoplast. RNA blotting analysis revealed that the LetAPX transcript expression was up-regulated by chilling, high light, exogenous salicylic acid (SA) and methyl viologen (MV). Over expression of LetAPX in tomatoes conferred tolerance to chilling stress by maintaining higher reduced glutathione (GSH) content, chlorophyll and APX activities compared with wild type (WT) plants. Furthermore, transgenic plants showed lower levels of hydrogen peroxide (H(2)O(2)) and ion leakage, lower malendialdehyde (MDA) content, higher net photosynthetic rate (Pn) and higher maximal photochemical efficiency of PSII (Fv/Fm). The oxidizable P700 decreased more obviously in WT than that in transgenic plants under chilling stress in low irradiance. The results suggested that over expression of tAPX played a key role both in alleviating photo inhibition of PSI and PSII and enhancing their tolerance to chilling stress.

A tomato (Lycopersicon esculentum Mill.) chloroplast glutathione reductase gene (LeGR) was isolated and antisense transgenic tomato lines were obtained. Under chilling stress, transgenic plants accumulated more H(2)O(2), leaked more electrolyte and showed lower net photosynthetic rate (Pn), maximal photochemical efficiency of PSII (Fv/Fm) and oxidizable P700 compared with wild-type (WT) plants. Transgenic seedlings were more suppressed in fresh-weight growth and lost more cotyledon chlorophyll. The decrease in the activity of ascorbate peroxidase (APX) was implied to be potentially relevant to the greater accumulation of H(2)O(2) in transgenic plants. Chilling treatment induced more decrease in the level of reducted glutathione (GSH) and redox ratio of glutathione in transgenic plants than in WT plants, but aroused more increase in GSSG in transgenic plants than in WT plants. Total glutathione displayed no change. Besides, chilling stress resulted in greater decreases in the level of reducted ascorbate (AsA), total ascorbate and redox ratio of ascorbate in transgenic plants than in WT plants, but led to equivalent degree of dehydroascorbate (DHA) increase in WT and transgenic plants. These assessments of glutathione-ascorbate cycle revealed that the decrease of glutathione reductase activity in transgenic plants affected glutathione regeneration, and consequently affected ascorbate regeneration and total ascorbate content. This resulted in a greater accumulation of H(2)O(2) and an enhanced sensitivity to chilling stress in transgenic plants. Moreover, a putative concept model of ecophysiological reaction was discussed.

Chinese cherry (Prunus pseudocerasus L.) is an allotetraploid species and exhibits natural self-compatibility. However, the full-length cDNA sequences, functional analysis and the transcripts of S-RNase alleles in Chinese cherry cultivars are not known. In the two cultivars Taixiaohongying and Laiyang Short Cherry with S1S2S3S4 genotypes, two S-RNases were transcribed in Northern blotting, and the two full-length cDNAs of S-RNase were cloned and analyzed. As the result, the transcribed S-RNases were S1-RNase and S2-RNase. The two complete cDNA sequences of S1-RNase and S2-RNase were registered as EU073938 and EU073939, respectively, and had characteristic structure of rosaceous S-RNases based on their sequences indicating that they had normal function for S-RNase in the style. The S3-RNase and S4-RNase were not transcribed in the style and were nonfunctional for S-RNase, so S(subscript 3m) and S(subscript 4m) could be used to represent the nonfunctional S3-RNase and S4-RNase. The phylogenetic analysis implied that the S-RNases of Prunus, including Chinese cherry, had lower intra-specific similarity and diverged earlier than the divergence of species in Prunus.

Monodehydroascorbate reductase (MDAR; EC 1.6.5.4) is crucial for AsA regeneration and essential for maintaining the reduced pool of AsA. And the amino acid residue C117 of chloroplastic MDAR is the conserved cysteine residue in MDAR isoforms. A series mutation of conserved amino acid residue cysteine117 (C117) was constructed to investigate its role in MDAR structural stability and activity. Our study revealed that mutation in this conserved residue could cause pronounced loss of activity and conformational changes. Spectroscopic experiments indicated that these mutations influenced transition from the molten globule intermediate to the native state in folding process. These results suggested that amino acid residue C117 played a relatively important role in keeping MDAR structural stability and activity.

The mechanism of high yield of winter wheat in the field at late growth period was investigated by measuring the photosynthetic characteristics of photosystem II (PSII) and xanthophylls cycle, which could provide physiological reference for breeding. Weimai 8 (W8), a super high yield cultivar, and Lumai 14 (L14), a control cultivar were object. The photosynthetic rate (Pn), parameters of chlorophyll fluorescence and chlorophyll content were measured. The Pn, maximum photochemical efficiency of PSII (Fv/Fm), quantum yield of PSII electron transport (ΦPSII), efficiency of excitation energy capture by open PSII reaction centers (Fv′/Fm′), and photochemical quenching coefficient (qP) were higher in Weimai 8 compared to that in Lumai 14, a commercial high yield cultivar. Furthermore, Weimai 8 showed a lower nonphotochemical quenching coefficient and a lower de-epoxidized ratio of the xanthophyll cycle pigments than of Lumai 14 at late growth period. At mature stage, chlorophyll content of different leaves decreased both in Weimai 8 and Lumai 14. Chlorophyll content in flag, second and third leaf from the top of plant decreased more in Lumai 14 than in Weimai 8. These results suggested that Weimai 8 had more antenna pigments to absorb light energy, and had higher photosynthetic capability and photochemical efficiency of PSII. The yield of Weimai 8 was also higher than that of Lumai 14.

A tomato (Lycopersicon esculentum) violaxanthin de-epoxidase gene (LeVDE) was isolated. The deduced amino acid sequence of LeVDE showed high identities with violaxanthin de-epoxidase in other plant species. RNA gel blot analysis showed that the mRNA accumulation of LeVDE in the wild-type (WT) was regulated by diurnal rhythm and temperature. RNA and protein gel blot analyses confirmed that the sense LeVDE was transferred into the tomato genome and overexpressed under the control of 35S-CaMV. The ratio of (A+Z)/(V+A+Z) and the values of non-photochemical quenching (NPQ) were higher in transgenic plants than those in WT under high light and chilling stress (4 degrees C). The net photosynthetic rate (Pn) decreased markedly in WT compared to transgenic lines under high light stress. The maximum quantum yield of primary photochemistry of PSII (Fv/Fm) in transgenic plants decreased more slowly during stresses and recovered faster than that in WT under optimal conditions. The oxidizable P700 in transgenic plants was higher than that in WT under chilling stress. These results suggest that overexpression of LeVDE increased the function of the xanthophyll cycle and alleviated photoinhibition of PSII and PSI in tomato during high light and chilling stress with low irradiance.