Publications by authors named "Ailian Qiu"

Bacterial wilt caused by is one of the most important diseases in solanaceous plants, including peppers. It generally tends to be more serious under warm-temperature and moist (WM) conditions than at moist room-temperature (RM) conditions. Although immunity mechanisms at room temperature have been intensively studied, the mechanisms underlying WM conditions remain poorly understood.

View Article and Find Full Text PDF

High temperature stress (HTS) is a serious threat to plant growth and development and to crop production in the context of global warming, and plant response to HTS is largely regulated at the transcriptional level by the actions of various transcription factors (TFs). However, whether and how homeodomain-leucine zipper (HD-Zip) TFs are involved in thermotolerance are unclear. Herein, we functionally characterized a pepper (Capsicum annuum) HD-Zip I TF CaHDZ15.

View Article and Find Full Text PDF

Plant diseases tend to be more serious under conditions of high-temperature/high-humidity (HTHH) than under moderate conditions, and hence disease resistance under HTHH is an important determinant for plant survival. However, how plants cope with diseases under HTHH remains poorly understood. In this study, we used the pathosystem consisting of pepper (Capsicum annuum) and Ralstonia solanacearum (bacterial wilt) as a model to examine the functions of the protein mildew resistance locus O 1 (CaMLO1) and U-box domain-containing protein 21 (CaPUB21) under conditions of 80% humidity and either 28 °C or 37 °C.

View Article and Find Full Text PDF

GSK3-like kinases have been mainly implicated in the brassinosteroids (BR) pathway and, therefore, in plant growth, development, and responses to abiotic stresses; however, their roles in plant immunity remain poorly understood. Herein, we present evidence that CaSK23, a putative GSK3/SHAGGY-like kinase in pepper, acts as a negative regulator in pepper's response to () inoculation (RSI). Data from quantitative RT-PCR (qRT-PCR) showed that the constitutively-expressed in pepper leaves was down-regulated by RSI, as well as by exogenously-applied salicylic acid (SA) or methyl jasomonate (MeJA).

View Article and Find Full Text PDF

The responses of pepper (Capsicum annuum) plants to inoculation with the pathogenic bacterium Ralstonia solanacearum and to high-temperature-high-humidity (HTHH) conditions were previously found to be coordinated by the transcription factors CaWRKY6 and CaWRKY40; however, the underlying molecular mechanism was unclear. Herein, we identified and functionally characterized CaHsfB2a, a nuclear-localized heat shock factor involved in pepper immunity to R. solanacearum inoculation (RSI) and tolerance to HTHH.

View Article and Find Full Text PDF

Tandem CCCH zinc finger (TZnF) proteins have been implicated in plant defence, but their role in pepper (Capsicum annuum) is unclear. In the present study, the role of CaC3H14, a pepper TZnF protein, in the immune response of pepper plants to Ralstonia solanacearum infection was characterized. When fused to the green fluorescent protein, CaC3H14 was localized exclusively to the nuclei in leaf cells of Nicotiana benthamiana plants transiently overexpressing CaC3H14.

View Article and Find Full Text PDF

In plants, Rho-related GTPases (Rops) are versatile molecular switches that regulate various biological processes, although their exact roles are not fully understood. Herein, we provide evidence that the ectopic expression of a Rop derived from Capsicum annuum, designated CaRop1, in tobacco plants modulates the response of these plants to Ralstonia solanacearum or aphid attack. The deduced amino acid sequence of CaRop1 harbors a conserved Rho domain and is highly homologous to Rops of other plant species.

View Article and Find Full Text PDF

The leucine-rich repeat (LRR) proteins play important roles in the recognition of corresponding ligands and signal transduction networks in plant defence responses. Herein, a novel LRR protein from Capsicum annuum, CaLRR51, was identified and characterized. It was localized to the plasma membrane and transcriptionally up-regulated by Ralstonia solanacearum infection (RSI), as well as the exogenous application of salicylic acid (SA), jasmonic acid (JA) and ethephon (ETH).

View Article and Find Full Text PDF

As Ca2+ sensors and effectors, calcium-dependent protein kinases (CDPKs) play important roles in plant growth, development, and response to environmental cues. However, no CDPKs have been characterized in Capsicum annuum thus far. Herein, a genome wide comprehensive analysis of genes encoding CDPKs and CDPK-related protein kinases (CRKs) was performed in pepper, a total of 31 CDPK genes and five closely related kinase genes were identified, which were phylogenetically divided into four distinct subfamilies and unevenly distributed across nine chromosomes.

View Article and Find Full Text PDF

Elicitins are elicitors that can trigger hypersensitive cell death in most Nicotiana spp., but their underlying molecular mechanism is not well understood. The gene Phytophthora capsici INF1 (PcINF1) coding for an elicitin from P.

View Article and Find Full Text PDF

High temperature (HT), high humidity (HH), and pathogen infection often co-occur and negatively affect plant growth. However, these stress factors and plant responses are generally studied in isolation. The mechanisms of synergistic responses to combined stresses are poorly understood.

View Article and Find Full Text PDF

ETHYLENE RESPONSE FACTORs (ERF) transcription factors (TFs) constitute a large transcriptional regulator family belonging to the AP2/ERF superfamily and are implicated in a range of biological processes. However, the specific roles of individual ERF family members in biotic or abiotic stress responses and the underlying molecular mechanism still need to be elucidated. In the present study, a cDNA encoding a member of ethylene response factor (ERF) transcription factor, CaERF5, was isolated from pepper.

View Article and Find Full Text PDF

Objective: By analyzing the function and mechanism of nitric oxide in initiating producing lignin peroxidases by phanerochaete chrysosporium, we studied the regulation mechanism triggering the secondary metabolism of white-rot fungi.

Methods: Mutant (pcR5305) and wild-type (pc530) strains of phanerochaete chrysosporium were respectively cultured under both the conditions of nitrogen limitation and nitrogen sufficiency. To compare their lignin peroxidases (LiP)-production and nitric oxide(NO)-production kinetics and their different influences on producing LiP after the NO donor Sodium Nitroprusside (SNP) and scavenger cPTIO were respectively added to the nitrogen limitation or sufficiency culture medium to show the function and mechanism of nitric oxide in initiating production of lignin peroxidases by white-rot fungi.

View Article and Find Full Text PDF

The ankyrin repeat-containing protein gene OsPIANK1 (AK068021) in rice (Oryza sativa L.) was previously shown to be upregulated following infection with the rice leaf blight pathogen Xanthomonas oryzae pv oryzae (Xoo). In this study, we further characterized the role of OsPIANK1 in basal defense against Magnaporthe oryzae (M.

View Article and Find Full Text PDF

Ethylene-responsive factors (ERFs) play diverse roles in plant growth, developmental processes and stress responses. However, the roles and underlying mechanism of ERFs remain poorly understood, especially in non-model plants. In this study, a full length cDNA of ERF gene was isolated from the cDNA library of Chinese cabbage.

View Article and Find Full Text PDF

WRKY transcription factors are encoded by large gene families across the plant kingdom. So far, their biological and molecular functions in nonmodel plants, including pepper (Capsicum annuum) and other Solanaceae, remain poorly understood. Here, we report on the functional characterization of a new group I WRKY protein from pepper, termed CaWRKY58.

View Article and Find Full Text PDF

WRKY proteins form a large family of plant transcription factors implicated in the modulation of numerous biological processes, such as growth, development and responses to various environmental stresses. However, the roles of the majority WRKY family members, especially in non-model plants, remain poorly understood. We identified CaWRKY40 from pepper.

View Article and Find Full Text PDF

Objective: Comparing the effects of different carbon-nitrogen nutrition and their consumption on laccase production, we studied the ecophysiological characteristics of Phanerochaete chrysosporium resisting nutritional repression, and the carbon-nitrogen physiological regulation mechanism of the white-rot fungi.

Methods: The mutant and the wild-type strains were respectively cultured under the conditions of: carbon and nitrogen limitation, carbon limitation and nitrogen sufficiency, carbon sufficiency and nitrogen limitation, carbon and nitrogen sufficiency, to compare their laccase-production kinetics, cell growth and glucose and ammonia nitrogen consumption to show the characteristics and the regulation pathway of carbon-nitrogen nutrition on laccase production.

Results: The wild-type strain produced 0.

View Article and Find Full Text PDF

Objective: To screen Phanerochaete chrysosporium mutants resisting nutritional repression and to characterize laccase produced by the mutants.

Methods: We used repeated UV mutagenesis and screened the mutant strains by using the guaiacol nitrogen sufficient differential medium. We characterized enzymes production mechanism of the nutritional regulation through comparing the differences of cell growth and enzyme-production kinetics under different nutritional conditions; We validated production of laccase by Phanerochaete chrysosporium through measurements of the heat treatment, removal of manganese ion and addition of the catalase.

View Article and Find Full Text PDF