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The low phosphorus (P) availability of acidic soils severely limits leguminous plant growth and productivity. Improving the soil P nutritional status can be achieved by increasing the P-content through P-fertilization or stimulating the mineralization of organic P via arbuscular mycorrhizal fungi (AMF) application; however, their corresponding impacts on plant and soil microbiome still remain to be explored. Here, we examined the effects of AMF-inoculation and P-fertilization on the growth of soybean with different P-efficiencies, as well as the composition of rhizo-microbiome in an acidic soil. The growth of recipient soybean NY-1001, which has a lower P-efficiency, was not significantly enhanced by AMF-inoculation or P-fertilization. However, the plant biomass of higher P-efficiency transgenic soybean PT6 was significantly increased by 46.74%–65.22% through AMF-inoculation. Although there was no discernible difference in plant biomass between PT6 and NY-1001 in the absence of AMF-inoculation and P-fertilization, PT6 had approximately 1.9–2.5 times the plant biomass of NY-1001 after AMF-inoculation. Therefore, the growth advantage of higher P-efficiency soybean was achieved through the assistance of AMF rather than P-fertilization in available P-deficient acidic soil. Most nitrogen (N)-fixing bacteria and some functional genes related to N-fixation were abundant in endospheric layer, as were the P-solubilizing Pseudomonas plecoglossicida, and annotated P-metabolism genes. These N-fixing and P-solubilizing bacteria were positive correlated with each other. Lastly, the two most abundant phytopathogenic fungi species accumulated in endospheric layer, they exhibited positive correlations with N-fixing bacteria, but displayed negative interactions with the majority of the other dominant non-pathogenic genera with potential antagonistic activity.

Purpose: According to the Chinese Stock Exchange rules, the listed companies’ management earnings forecasts (MEFs) are divided into mandatory and voluntary earnings forecasts. Different information disclosure mechanisms may bring different economic consequences. Compared with the former, when, how frequently and what kind of voluntary earnings forecasts are disclosed almost entirely depends on the discretion of managers and the major shareholders[1]. The purpose of this paper is to examine whether listed companies’ voluntary earnings forecasts have self-benefited motives before the major shareholders’ selling of original non-tradable shares and how the capital market reacts in China. Design/methodology/approach: This paper uses multiple regression analyses to examine the influence of the major shareholders’ non-tradable shares selling motives on MEFs’ type and frequency of A-share listed companies and makes robust tests using the difference in difference model (DID). Findings: In the paper, it is found that before the major shareholders’ selling of original non-tradable shares, managers of listed companies are prone to release positive voluntary MEFs; during the shares reduction year of the major shareholders, the disclosure frequency of MEFs is much higher; these forecasts before the major stockholders’ selling have significant higher excess market returns. The evidence suggests that voluntary positive MEFs are for the major shareholders’ self-interested motive rather than for the open, fair and just disclosure purpose that damages the allocation efficiency of the capital market. Originality/value: This paper enriches the understanding of voluntary MEFs’ incentives literature and provides scientific evidence to improve the supervision of information disclosure and insider trading in Chinese security market.

Seasonal pluvial‐drought transition processes are unique natural phenomena. To explore possible mechanisms, we considered Southwest China (SWC) as the study region and comprehensively investigated the temporal evolution or spatial patterns of large‐scale and regional atmospheric variables with the simple method of Standardized Anomalies (SA). Some key procedures and results include the following: (1) Because regional atmospheric variables are more directly responsible for the transition processes, we investigate it in detail. The temporal evolution of net vertical integral water vapor flux (net VIWVF) across SWC, together with vertical SA‐based patterns of regional horizontal divergence (D) and vertical motion (ω), coincides well with pluvial‐drought transition processes. (2) With respect to large‐scale circulation patterns, a well‐organized Eurasian (EU) Pattern is one important feature during the pluvial‐drought transitions over SWC. (3) Based on these large‐scale and regional atmospheric anomalous features, relevant SA‐based indices were built, to explore the possibility of simulating drought development using previous pluvial anomalies. As a whole, simulated drought development only with SA‐based indices of large‐scale circulation patterns does not perform well. Further, it can be improved a lot when SA‐based indices of regional Dand net VIWVF are introduced. (4) In addition, the potential drought prediction using pluvial anomalies, together with the deep understanding of physical mechanisms responsible for pluvial‐drought transitions, need to be further explored. Standardized Anomalies of net vertical integral water vapor flux can show high correlation with regional pluvial‐drought transitionsVertical patterns of horizontal divergence and vertical motion (ω) anomalies coincide well with the pluvial‐drought transitionsThe drought portion of some pluvial‐drought transition processes can be simulated with previous pluvial anomalies

Isoflavonoids are a group of secondary metabolites common to leguminous plants that play roles in nodulation and defense responses. Isoflavone synthase (IFS) catalyzes the key entry point step of isoflavone biosynthesis from the general phenylpropanoid pathway. We have cloned the 5′ upstream regions of the genes encoding the two isoflavone synthase isoforms from soybean. We characterized the tissue-specific expression patterns of IFS1and IFS2genes of soybean by quantitative RT-PCR. Isoflavone synthase transcripts were detected primarily in the roots and seeds. In transgenic soybean plants in which the IFS1promoter drove expression of the bacterial uidA(GUS) gene, the expression was localized to the root epidermis and root hairs. We detected differential tissue-specific expression of IFS1:GUS in response to nodulation and defense signals. Bradyrhizobium japonicum, a diazotropic symbiont of soybean, induced the expression of IFS1:GUS in root hairs and xylem poles in the young differentiation zone of the root. This observation suggests novel roles for isoflavonoids in nodulation. The defense related hormone salicylic acid induced the expression of IFS1:GUS in all cell types of the root. We also noticed corresponding alterations in the transcript levels of IFS1and IFS2in response to B. japonicumor salicylic acid as identified by quantitative RT-PCR. Using hairy root transformed soybean composite plants, we have identified regions of the IFS1and IFS2promoters mediating response to B. japonicum. We have also shown conserved root-specific expression of IFS1in rice and Arabidopsis. The expression pattern of IFS1in soybean is consistent with the physiological roles of isoflavonoids as defense compounds against pathogens and signal molecules to symbiotic bacteria in soybean.

Screening a random oligonucleotide library using a modified differential Southwestern method, we generated a root-enriched library of candidate promoter cis-elements that interacted with maize root nuclear proteins. Three candidates that were examined formed root-specific DNA-protein complexes in electrophoretic mobility shift assays. When fused upstream to a synthetic core (SynCore) promoter driving the GUS reporter gene, only one of the three candidates, designated ROL6, generated significantly higher levels of root-preferred expression in particle bombardment-mediated transient assays compared to the SynCore promoter-driven GUS gene. The other two elements showed little or no effect on promoter activiry. The addition of the maize Ubi1 flanking region (-865 to -54 bp) upstream of the ROL6-SynCore promoter further enhanced root-preferred expression approximately 2-fold over the high level of expression of the maize Ubi1 promoter alone. Based on public database searches, the ROL6 sequence shows some embedded MYBbinding motifs yet very little homology to any known plant cis-acting elements and may contain one or more novel root-preferred cis-acting elements. Overall these results demonstrate first the effectiveness of using this screening approach to isolate functionally active promoter elements and second that ROL6 functions as a root-preferred activator and can be used to modify the expression pattern of transgenes.

Arabidopsis cDNA clones of GF14 proteins originally were isolated on the basis of their association with the G-box DNA/protein complex by a monoclonal antibody screening approach. GF14 proteins are homologous to the 14-3-3 family of mammalian proteins. Here we demonstrate that recombinant GF14 ?, one member of the Arabidopsis GF14 protein family, is a dimeric protein that possesses many of the attributes of diverse mammalian 14-3-3 homologues. GF14 ? activates rat brain tryptophan hydroxylase and protein kinase C in a manner similar to the bovine 14-3-3 protein. It also activates exoenzyme S of Pseudomonas aeruginosa as does bovine brain factor activating exoenzyme S (FAS), which is itself a member of 14-3-3 proteins. In addition, GF14 ? binds calcium, as does the human 14-3-3 homologue reported to be a phospholipase A2. These results indicate that a single isoform of this plant protein family can have multiple functions and that individual GF14 isoforms may have multiple roles in mediating signal transductions in plants. However, GF14 ? does not regulate growth in an in vivo test for functional similarity to the yeast 14-3-3 homologue, BMH1. Thus, while a single plant GF14 isoform can exhibit many of the biochemical attributes of diverse mammalian 14-3-3 homologues, open questions remain regarding the physiological functions of GF14/14-3-3 proteins.

There is a 36 bp tract of extreme homopurine/homopyrimidine (PuPy) asymmetry in the maize Adh1 gene promoter (from -44 to -79) that is S1-hypersensitive in plasmids under supercoil tension. Oligodeoxynucleotides corresponding to the PuPy tract were designed to examine the secondary structure of the region and address the possible role of the tract in gene regulation. On the basis of oligodeoxynucleotide band-shift and DNase I footprinting analyses, it was concluded that the homopyrimidine oligodeoxynucleotide can form a triple helix with the duplex PuPy tract in vitro. Transient assays in protoplasts, suspension cells, and seedling roots show that the homopyrimidine oligodeoxynucleotide is also capable of repressing Adh1-GUS gene expression during co-transformation, presumably by the formation of a triple helix with the PuPy tract in vivo. The complementary homopurine oligodeoxynucleotide would not form a triple helix in vitro, nor would it repress Adh1-GUS in vivo. We propose that triple helix formation is a potential regulatory phenomenon in vivo, and that an intraregion triple helix could occur within the Adh1 promoter via the formation of H-DNA.

The 14-3-3 proteins constitute a family of dimeric proteins that are involved in many cellular functions. At least two mammalian 14-3-3 proteins can form heterodimers and the approximate regions important for dimerization have been identified. In this study, we demonstrate that eightArabidopsisand one maize 14-3-3 protein can dimerize with each other and with themselves. Native gel Western analysis ofArabidopsiscell extract also suggests the presence of 14-3-3 heterodimersin vivo.Finally, we identified the domains of one 14-3-3 protein that are sufficient for homodimerization and heterodimerization. These data support the hypothesis that evolutionarily divergent 14-3-3 proteins can interact with each other to form diverse molecular modulators or adapters in signaling pathways.

The GF14 family of proteins in Arabidopsis thaliana consists of a homologous group of polypeptides ranging in size from ~27 kDa to ~32 kDa. As a group, GF14 proteins are also homologous to a family of mammalian proteins most commonly referred to as 14-3-3 proteins. Several distinct and different biochemical activities have been historically attributed to the various isoforms of the mammalian 14-3-3 proteins. These data present the possibility that the various activities are performed by functionally distinct lineages of the gene family. Here we present phylogenetic analyses based on the derived amino acid sequences of five GF14 isoforms expressed in Arabidopsis suspension-cultured cells. A high degree of sequence integrity is apparent in the various Arabidopsis isoforms, and the overall structures of the plant forms are quite conserved with regard to the structures of the known mammalian forms. These gene phylogenies indicate no evolutionary conservation of specific isoform lineages within both plants and animals. Rather, the evolutionary history of this protein appears to be characterized by a separate radiation of plant and animal forms from a common ancestral sequence. Even though the plant and animal forms have evolved independently since that ancestral split, large domains are conserved in both major lineages.

Our previous study indicates that hydrochlorothiazide inhibits transforming growth factor (TGF)‐β/Smad signaling pathway, improves cardiac function and reduces fibrosis. We determined whether these effects were common among the diuretics and whether angiotensin II receptor type 1 (AT1) signaling pathway played a role in these effects. Heart failure was produced by ligating the left anterior descending coronary artery in adult male Sprague Dawley rats. Two weeks after the ligation, 70 rats were randomly divided into five groups: sham‐operated group, control group, valsartan group (80 mg/kg/d), hydrochlorothiazide group (12.5 mg/kg/d) and furosemide group (20 mg/kg/d). In addition, neonatal rat ventricular fibroblasts were treated with angiotensin II. After eight‐week drug treatment, hydrochlorothiazide group and valsartan group but not furosemide group had improved cardiac function (ejection fraction was 49.4±2.1%, 49.5±1.8% and 39.9±1.9%, respectively, compared with 40.1±2.2% in control group), reduced cardiac interstitial fibrosis and collagen volume fraction (9.7±1.2%, 10.0±1.3% and 14.1±0.8%, respectively, compared with 15.9±1.1% in control group), and decreased expression of AT1, TGF‐β and Smad2 in the cardiac tissues. In addition, hydrochlorothiazide reduced plasma angiotensin II and aldosterone levels. Furthermore, hydrochlorothiazide inhibited angiotensin II‐induced TGF‐β1 and Smad2 protein expression in the neonatal rat ventricular fibroblasts. Our study indicates that the cardiac function and remodeling improvement after ischemic heart failure may not be common among the diuretics. Hydrochlorothiazide may reduce the left ventricular wall stress and angiotensin II signaling pathway to provide these beneficial effects.