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Rice tillers are a major yield component regulated by phytohormones and nutrients. How nutrients interact with phytohormones to control tillering remains largely elusive. Here, we report a novel mechanism by which the transcription factor NIN-like protein 4 (OsNLP4) integrates nitrogen (N)-iron (Fe) nutrient signals to promote tillering by repressingOsD3in strigolactone (SL) signaling. We show that the N-Fe balance modulates OsNLP4 nuclear accumulation, which is increased by Fe through H2O2reduction. Furthermore, OsNLP4 upregulates multiple H2O2scavenging genes, providing a positive regulatory loop for OsNLP4 nuclear accumulation. Our findings uncover a fundamental mechanism by which the OsNLP4-OsD3 module integrates N-Fe nutrient signals to downregulate SL signaling and thereby promote rice tillering and yield, thus facilitating sustainable agriculture worldwide.

Nutrients must be balanced for optimal plant growth. However, the potential significance of balanced nitrogen-iron (N-Fe) for improving crop yield and nitrogen use efficiency (NUE) has never been addressed. Here, we show that balanced N-Fe substantially increases tiller number and boosts yield and NUE in rice and wheat. NIN-like protein 4 plays a pivotal role in maintaining the N-Fe balance by coordinately regulating the expression of multiple genes in N and Fe metabolism and signaling. Moreover, we show that foliar spraying of balanced N-Fe at the tillering stage can effectively increase rice tillers, yield and NUE in the field, which can be reproduced with wheat. Our findings provide guidelines for innovative fertilization to reduce N fertilizer input and promote yield, thus benefitting environment-friendly and sustainable agriculture worldwide.

Additional file 1. Figure S1: Uncut blots for Figure 2C, 3D, 5A and 5B. Figure S2: Uncut blots for Figure 5C, 5D, 6A, 6B, 6C and 6D.

Nitrogen (N) is indispensable for crop growth and yield, but excessive agricultural application of nitrogenous fertilizers has generated severe environmental problems. A desirable and economical solution to cope with these issues is to improve crop nitrogen use efficiency (NUE). Plant NUE has been a focal point of intensive research worldwide, yet much more has to be learned about its genetic determinants and regulation. Here, we show that rice NIN-LIKE PROTEIN 1 (OsNLP1) plays a fundamental role in N utilization. OsNLP1 protein localizes in nucleus and its transcript level is rapidly induced by N starvation. Overexpression of OsNLP1 improves plant growth, grain yield and NUE under different N conditions while knockout of OsNLP1 impairs grain yield and NUE under N limiting conditions. OsNLP1 regulates nitrate and ammonium utilization by cooperatively orchestrating multiple N uptake and assimilation genes. Chromatin immunoprecipitation and yeast-one-hybrid assays show that OsNLP1 can directly bind to the promoter of these genes to activate their expression. Therefore, our results demonstrate that OsNLP1 is a key regulator of N utilization and represents a potential target for improving NUE and yield in rice.One-sentence summaryOsNLP1 rapidly responds to N availability, enhances N uptake and assimilation, and holds great potential in promoting high yield in rice.

Purpose The purpose of this study is to examine whether the corruption level of a country is associated with a firm’s decision to choose Big 4 versus non-Big 4 auditors. In addition, the authors examine whether firms that are cross-listed in a country with a corruption level different from that of the home country are more likely to appoint Big 4 auditors. Design/methodology/approach Based on a sample of 185,549 firm-year observations from 78 countries over 2003-2012, panel regression analysis is used to investigate the research questions. Findings The authors find a negative association between corruption and the propensity to hire Big 4 auditors and that cross-listed firms are more likely to hire Big 4 auditors than their domestic counterparts. Interestingly, the authors find that when firms cross-list in less corrupt countries relative to their home countries, firms are more likely to hire Big 4 auditors. However, this tendency disappears when firms cross-list in more corrupt countries. Originality/value The authors contribute to the audit choice literature by providing evidence that the political environment, as manifested in the corruption level of a country, plays a role in the decision to choose Big 4 versus non-Big 4 auditors. The study complements the prior auditor choice literature, which focuses mostly on single countries such as the USA, by expanding the scope to 78 countries. Furthermore, the authors enhance the understanding of how the absolute and relative performance of the political environment affects cross-listed firms’ choice of auditors.

Nitrogen (N) is an essential macronutrient for crop growth and yield. Improving the N use efficiency (NUE) of crops is important to agriculture. However, the molecular mechanisms underlying NUE regulation remain largely elusive. Here we report that the OsNLP3 (NIN-like protein 3) regulates NUE and grain yield in rice under N sufficient conditions. OsNLP3 transcript level is significantly induced by N starvation and its protein nucleocytosolic shuttling is specifically regulated by nitrate. Loss-of-function of OsNLP3 reduces plant growth, grain yield, and NUE under sufficient nitrate conditions, whereas under low nitrate or different ammonium conditions, osnlp3 mutants show no clear difference from the wild type. Importantly, under sufficient N conditions in the field, OsNLP3 overexpression lines display improved grain yield and NUE compared with the wild type. OsNLP3 orchestrates the expression of multiple N uptake and assimilation genes by directly binding to the nitrate-responsive cis-elements in their promoters. Overall, our study demonstrates that OsNLP3, together with OsNLP1 and OsNLP4, plays overlapping and differential roles in N acquisition and NUE, and modulates NUE and the grain yield increase promoted by N fertilizer. Therefore, OsNLP3 is a promising candidate gene for the genetic improvement of grain yield and NUE in rice.

Seed germination is a crucial transition point in plant life and is tightly regulated by environmental conditions through the coordination of two phytohormones, gibberellin and abscisic acid (ABA). To avoid unfavorable conditions, plants have evolved safeguard mechanisms for seed germination. Here, we report a novel function of the Arabidopsis MADS-box transcription factor ARABIDOPSIS NITRATE REGULATED 1 (ANR1) in seed germination.ANR1knockout mutant is insensitive to ABA, salt, and osmotic stress during the seed germination and early seedling development stages, whereasANR1-overexpressing lines are hypersensitive. ANR1 is responsive to ABA and abiotic stresses and upregulates the expression ofABI3to suppress seed germination.ANR1andABI3have similar expression pattern during seed germination. Genetically,ABI3acts downstream ofANR1. Chromatin immunoprecipitation and yeast-one-hybrid assays showed that ANR1 could bind to theABI3promoter to regulate its expression. In addition, ANR1 acts synergistically with AGL21 to suppress seed germination in response to ABA as evidenced byanr1 agl21double mutant. Taken together, our results demonstrate that the ANR1 plays an important role in regulating seed germination and early post-germination growth. ANR1 and AGL21 together constitutes a safeguard mechanism for seed germination to avoid unfavorable conditions.

SYNOPSIS This paper examines the association between macroeconomic uncertainty and audit fees. Using the volatility index from the Chicago Board Option Exchange to proxy for macroeconomic uncertainty and a sample of U.S. firms from 2002 to 2014, we document that macroeconomic uncertainty is negatively associated with audit fees and that the fee reduction during periods of high uncertainty is more pronounced for firms appointing Big 4 and specialist auditors and for firms with better financial condition. The results are consistent with the notions that market-wide uncertainties give firms a greater advantage over auditors during the price negotiation process and that the effect of macroeconomic uncertainty on audit fees varies across auditor and client attributes. Overall, this paper provides evidence that the macroeconomic environment plays a role in determining audit fees. JEL Classifications: M42. Data Availability: Data used are from public sources identified in the paper.

Nitrogen (N) is an essential macronutrient for crop growth and yield, but excessive application of N fertilizer has caused serious environmental pollution and greatly increased the cost of agricultural production. One of the effective and economical solutions to this dilemma is to improve the N use efficiency (NUE) of crops. Although some components involved in regulating NUE have been identified, the underlying molecular mechanism remains largely elusive in rice. Here we report that the OsNLP3 (NIN-like protein 3) is an important regulator in NUE and grain yield under nitrate-sufficient conditions. Both NUE and grain yield were significantly improved by enhanced OsNLP3 expression in the field, but reduced in osnlp3 mutants. The expression of OsNLP3 responds to both nitrate and ammonium, while OsNLP3 nuclear retention is only induced by nitrate, not by ammonium. OsNLP3 regulates the expression of a set of genes involved in N transport and assimilation by directly binding to the nitrate-responsive cis-element in the promoters of these genes. Our study demonstrates that OsNLP3 is significant for the regulation of NUE and grain yield, particularly in nitrate-rich conditions, thus providing a candidate for improving NUE and grain yield in rice.

Summary Nitrogen (N) is one of the key essential macronutrients that affects rice growth and yield. Inorganic N fertilizers are excessively used to boost yield and generate serious collateral environmental pollution. Therefore, improving crop N use efficiency (NUE) is highly desirable and has been a major endeavour in crop improvement. However, only a few regulators have been identified that can be used to improve NUE in rice to date. Here we show that the rice NIN‐like protein 4 (OsNLP4) significantly improves the rice NUE and yield. Field trials consistently showed that loss‐of‐OsNLP4 dramatically reduced yield and NUE compared with wild type under different N regimes. In contrast, the OsNLP4 overexpression lines remarkably increased yield by 30% and NUE by 47% under moderate N level compared with wild type. Transcriptomic analyses revealed that OsNLP4 orchestrates the expression of a majority of known N uptake, assimilation and signalling genes by directly binding to the nitrate‐responsive cis‐element in their promoters to regulate their expression. Moreover, overexpression of OsNLP4 can recover the phenotype of Arabidopsis nlp7 mutant and enhance its biomass. Our results demonstrate that OsNLP4 plays a pivotal role in rice NUE and sheds light on crop NUE improvement.

Nitrogen (N) is one of the key essential macronutrients that affects rice growth and yield. Inorganic N fertilizers are excessively used to boost yield and generate serious collateral environmental pollution. Therefore, improving crop N use efficiency (NUE) is highly desirable and has been a major endeavor in crop improvement. However, only a few regulators have been identified that can be used to improve NUE in rice to date. Here we show that the NIN-like protein OsNLP4 significantly improves the rice NUE and yield. Field trials consistently showed that loss-of-OsNLP4 dramatically reduced yield and NUE compared with wild type under different N regimes. In contrast, the OsNLP4 overexpression lines remarkably increased yield by 30% and NUE by 47% under moderate N level compared with wild type. Transcriptomic analyses revealed that OsNLP4 orchestrates the expression of a majority of known N uptake, assimilation and signaling genes by directly binding to the nitrate-responsive cis-element in their promoters to regulate their expression. Moreover, overexpression of OsNLP4 can recover the phenotype of Arabidopsis nlp7 mutant and enhance its biomass. Our results demonstrate that OsNLP4 is a master regulator of NUE in rice and sheds light on crop NUE improvement.

This paper examines the association between the corruption level of a country and audit market concentration. Using a sample from 78 countries over the 2003–2012 period, we document a positive asso...

This paper examines how changes in the credibility of financial reporting affect analyst behavior. Using a sample of restatement firms experiencing a substantial change in credibility over 1997–2006, we document that restatements have a long-lived effect on analyst behavior and that analysts differentiate between restatements caused by irregularities and those caused by errors. We find that while irregularity restatement firms exhibit a reduction in analyst coverage and forecast accuracy and an increase in forecast dispersion in the post-restatement period, other restatement firms exhibit only an increase in forecast error. Finally, we find evidence to suggest that remedial actions reduce the effect of irregularity restatements on analyst behavior. Overall, these results are consistent with the notion that restatements affect analyst behavior in forming judgements regarding subsequent earnings announcements.

This paper examines whether restatements affect trading volume reactions to subsequent earnings announcements. It closely follows the theoretical model developed by Kim and Verrecchia (J Account Econ 24:395–419, 1997) that decomposes the trading volume reactions around earnings announcements into the effects of pre-disclosure and event-period private information, and examines whether restatements change the trading volume reactions to earnings announcements in the post-restatement period. We find that restatements increase the degree of differential event-period information, leading to more divergent interpretation of earnings announcements subsequent to restatements. We also find that investors have less differential pre-disclosure private information in the post-restatement period, consistent with the view that investors’ beliefs converge when facing higher uncertainty in the information environment. Finally, focusing on irregularity restatement firms, we document that the effect of restatements on trading volume is more pronounced for firms announcing restatements after the passage of the Sarbanes–Oxley Act and after dismissing auditors and experiencing executive turnover. Overall, these results indicate that restatements affect investors’ behavior in forming judgments regarding earnings announcements.

The gaseous hormone ethylene participates in many physiological processes in plants. Ethylene-inhibited root elongation involves PIN-FORMED2 (PIN2)-mediated basipetal auxin transport, but the molecular mechanisms underlying the regulation of PIN2 function by ethylene (and therefore auxin distribution) are poorly understood. Here, we report that the plant-specific and ethylene-responsive HD-Zip gene HB52 is involved in ethylene-mediated inhibition of primary root elongation in Arabidopsis thaliana. Biochemical and genetic analyses demonstrated that HB52 is ethylene responsive and acts downstream of ETHYLENE-INSENSITIVE3 (EIN3). HB52 knockdown mutants displayed an ethylene-insensitive phenotype during primary root elongation, while its overexpression resulted in short roots, as observed in ethylene-treated plants. In addition, root auxin distribution and gravitropism were impaired in HB52 knockdown and overexpression lines. Consistent with these findings, in vitro and in vivo binding experiments showed that HB52 regulates the expression of auxin transport-related genes, including PIN2, WAVY ROOT GROWTH1 (WAG1), and WAG2 by physically binding to their promoter regions. These findings suggest that HB52 functions in the ethylene-mediated inhibition of root elongation by modulating the expression of auxin transport components downstream of EIN3, revealing a mechanism in which HB52 acts as an important node in the crosstalk between ethylene and auxin signaling during plant growth and development.

The gaseous hormone ethylene participates in many physiological processes of plants. It is well known that ethylene-inhibited root elongation involves basipetal auxin delivery requiring PIN2. However, the molecular mechanism how ethylene regulatesPIN2is not well understood. Here, we report that the ethylene-responsive HD-Zip geneHB52is involved in ethylene-mediated inhibition of primary root elongation. Using biochemical and genetic analyses, we demonstrated thatHB52is ethylene-responsive and acts immediately downstream of EIN3.HB52knock-down mutants are insensitive to ethylene in primary root elongation while the overexpression lines have dramatically shortened roots like ethylene treated plants. Moreover, HB52 upregulatesPIN2, WAG1, andWAG2by directly binding to their promoter, leading to an enhanced basipetal auxin delivery to the elongation zone and thus inhibiting root growth. Our work uncovers HB52 as an important crosstalk node between ethylene signaling and auxin transport in root elongation.

Drought and salinity are two major environmental factors limiting crop production worldwide. Improvement of drought and salt tolerance of crops with transgenic approach is an effective strategy to meet the demand of the ever-growing world population. Arabidopsis ENHANCED DROUGHT TOLERANCE1/HOMEODOMAIN GLABROUS11 (AtEDT1/HDG11), a homeodomain-START transcription factor, has been demonstrated to significantly improve drought tolerance in Arabidopsis, tobacco, tall fescue and rice. Here we report that AtHDG11 also confers drought and salt tolerance in upland cotton (Gossypium hirsutum) and woody plant poplar (Populus tomentosa Carr.). Our results showed that both the transgenic cotton and poplar exhibited significantly enhanced tolerance to drought and salt stress with well-developed root system. In the leaves of the transgenic cotton plants, proline content, soluble sugar content and activities of reactive oxygen species-scavenging enzymes were significantly increased after drought and salt stress compared with wild type. Leaf stomatal density was significantly reduced, whereas stomatal and leaf epidermal cell size were significantly increased in both the transgenic cotton and poplar plants. More importantly, the transgenic cotton showed significantly improved drought tolerance and better agronomic performance with higher cotton yield in the field both under normal and drought conditions. These results demonstrate that AtHDG11 is not only a promising candidate for crops improvement but also for woody plants.

Crystallizer steel belt feeding technology make use of melt’s fusion decalescence, controlling the distribution of melt temperature field, restrain the columnar crystal’s growing to eliminate the composition segregation and internal loose of continuous casting. And it will improve the continuous casting’s quality. By discussing the effect of casting speed, the size of steel, casting section and other factors on the steel belt feeding speed, making comparison of different casting section get strip suitable feeding speed and range of strip size, combining with a steel for steel strip feeding test mold, its theoretical and practical production results the basic agreement

Continuous casting mold feeding steel strip is a new technology to improve the organization and the equiaxed crystal ratio of casting slab. It is researched in one Steel Mill taking low carbon steel Q235B, 250 * 1600mm billet as the research object. Effects of the vibration feeding steel strip on the slab structure and performance is studied. Results show that, porosity in the center of cast billet and macro segregation of dispersion decreased through the continuous casting mould vibration feeding steel strip technology, which can improve the quality of macro structure and reduce the chemical heterogeneity shaft direction to the regional and then improve the plasticity in thick rolling plate.

Abeta accumulation, a hallmark of Alzheimer's disease, promotes the disease progress in multiple facets. Abeta is formed through amyloidogenic cleavage pathway of amyloid precursor protein (APP). Production of Abeta can be decreased via activation of 5-HT2C receptor, which enhances alternative APP non-amyloidogenic cleavage. Besides, as one of the best characterized Aβ degrading enzymes, neprilysin (NEP) in AD progress has drawn more and more attention. We investigated whether there exists any connection between 5-HT2C receptor and NEP expression. The mRNA and protein expressions of NEP were increased after treatment of 5-HT2C receptor agonist RO-60-0175 in concentration- and time-dependent manners, and NEP expression was decreased after treatment of 5-HT2C receptor antagonist SB242084 correspondingly. These results suggest that 5-HT2C receptor may inhibit the Abeta formation by promoting NEP expression. The underlying mechanism will be explored in follow-up study and may provide potential target for AD therapy.

SUMMARY MADS-box transcription factor AGL21 is responsive to several phytohormones as well as environmental cues and positively regulates auxin accumulation in lateral root primordia and lateral roots by enhancing local auxin biosynthesis, thus stimulating lateral root initiation and growth. Therefore, AGL21 may be involved in various environmental and physiological signals-mediated lateral root development., Plant root system morphology is dramatically influenced by various environmental cues. The adaptation of root system architecture to environmental constraints, which mostly depends on the formation and growth of lateral roots, is an important agronomic trait. Lateral root development is regulated by the external signals coordinating closely with intrinsic signaling pathways. MADS-box transcription factors are known key regulators of the transition to flowering and flower development. However, their functions in root development are still poorly understood. Here we report that AGL21, an AGL17-clade MADS-box gene, plays a crucial role in lateral root development. AGL21 was highly expressed in root, particularly in the root central cylinder and lateral root primordia. AGL21 overexpression plants produced more and longer lateral roots while agl21 mutants showed impaired lateral root development, especially under nitrogen-deficient conditions. AGL21 was induced by many plant hormones and environmental stresses, suggesting a function of this gene in root system plasticity in response to various signals. Furthermore, AGL21 was found positively regulating auxin accumulation in lateral root primordia and lateral roots by enhancing local auxin biosynthesis, thus stimulating lateral root initiation and growth. We propose that AGL21 may be involved in various environmental and physiological signals-mediated lateral root development and growth.