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This work aimed to explore the clinical application value of CT imaging technology based on the optimal Atlas segmentation algorithm (OASA) in the diagnosis of pediatric mycoplasma pneumonia (MP). Eighty-eight children with MP were selected and divided into group A (CT image based on the OASA) and group B (chest X-ray) according to the diagnosis methods. The detection rate, image feature performance, and image quality satisfaction of the two groups of children were compared. The results showed that the detection rate of group A was 97.73% and that of group B was 95.46%, and there was no considerable difference between the two ( P > 0.05). The pleural effusion detection rate of children in group A was evidently superior to that of X-ray group, while the increased bronchovascular shadows’ detection rate was greatly inferior to that of X-ray group ( P P > 0.05). CT image quality satisfaction (98.50%) was higher versus X-ray (79.46%) ( P

Seed germination and seedling establishment are important for the reproductive success of plants, but seeds and seedlings typically encounter constantly changing environmental conditions. By inhibiting seed germination and post-germinative growth through the PYR1/PYL/RCAR ABA receptors and PP2C co-receptors, the phytohormone abscisic acid (ABA) prevents premature germination and seedling growth under unfavorable conditions. However, little is known about how the ABA-mediated inhibition of seed germination and seedling establishment is thwarted. Here, we report that ABA Signaling Terminator (ABT), a WD40 protein, efficiently switches off ABA signaling and is critical for seed germination and seedling establishment. ABT is induced by ABA in a PYR1/PYL/RCAR-PP2C-dependent manner. Overexpression of ABT promotes seed germination and seedling greening in the presence of ABA, whereas knockout of ABT has the opposite effect. We found that ABT interacts with the PYR1/PYL/RCAR and PP2C proteins, interferes with the interaction between PYR1/PYL4 and ABI1/ABI2, and hampers the inhibition of ABI1/ABI2 by ABA-bound PYR1/PYL4, thereby terminating ABA signaling. Taken together, our results reveal a core mechanism of ABA signaling termination that is critical for seed germination and seedling establishment in Arabidopsis.

Abscisic acid (ABA) plays crucial roles in plant response to environmental stresses and development. The clade A phosphatases (PP2Cs) play a crucial role in ABA signaling. However, little is known about the details regarding PP2Cs family genes in Brassica juncea var. tumida. Here, 20 clade A PP2Cs family genes were identified in tuber mustard genome, including BjuABI1s, BjuABI2s, BjuAHG1s, BjuAHG3s, BjuHAB1, BjuHAB2s, BjuHAI1s, BjuHAI2s and BjuHAI3. The promoters of BjuPP2Cs family genes contained various of cis-acting elements, such as ABRE, GT1GMSCAM4, ARFAT and MYB1AT. We also analyzed the expression pattern of clade A BjuPP2Cs under abiotic stresses (low temperature, NaCl and ABA) treatment, pathogen Plasmodiophora brassicae treatment and different stages of stem swollen. The results suggested that clade A BjuPP2Cs regulated tuber mustard response to P. brassicae to mediate the formation of clubroot and might play roles in stem swelling and response to abiotic stresses. This study provides valuable information for further functional investigations of clade A PP2Cs family genes in B. juncea var. tumida.

DELLA (GAI/RGA/RGL1/RGL2/RGL3) proteins are key negative regulators in GA (gibberellin) signaling and are involved in regulating plant growth as a response to environmental stresses. It has been shown that the DELLA protein PROCERA (PRO) in tomato promotes drought tolerance, but its molecular mechanism remains unknown. Here, we showed that the gai-1 (gibberellin insensitive 1) mutant (generated from the gai-1 (Ler) allele (with a 17 amino acid deletion within the DELLA domain of GAI) by backcrossing gai-1 (Ler) with Col-0 three times), the gain-of-function mutant of GAI (GA INSENSITIVE) in Arabidopsis, increases drought tolerance. The stomatal density of the gai-1 mutant was increased but its stomatal aperture was decreased under abscisic acid (ABA) treatment conditions, suggesting that the drought tolerance of the gai-1 mutant is a complex trait. We further tested the interactions between DELLA proteins and ABF2 (abscisic acid (ABA)-responsive element (ABRE)-binding transcription factors) and found that there was a strong interaction between DELLA proteins and ABF2. Our results provide new insight into DELLA proteins and their role in drought stress tolerance.

The Salt Overly Sensitive (SOS) pathway in Arabidopsis thaliana plays important roles in maintaining appropriate ion homeostasis in the cytoplasm and regulating plant tolerance to salinity. However, little is known about the details regarding SOS family genes in the tuber mustard crop (Brassica juncea var. tumida). Here, 12 BjSOS family genes were identified in the B. juncea var. tumida genome including two homologous genes of SOS1, one and three homologs of SOS2 and SOS3, two homologs of SOS4, two homologs of SOS5 and two homologs of SOS6, respectively. The results of conserved motif analysis showed that these SOS homologs contained similar protein structures. By analyzing the cis-elements in the promoters of those BjSOS genes, several hormone- and stress-related cis-elements were found. The results of gene expression analysis showed that the homologous genes were induced by abiotic stress and pathogen. These findings indicate that BjSOS genes play crucial roles in the plant response to biotic and abiotic stresses. This study provides valuable information for further investigations of BjSOS genes in tuber mustard.

Abscisic acid (ABA) plays important roles in multiple physiological processes, such as plant response to stresses and plant development. The ABA receptors pyrabactin resistance (PYR)/ PYR1-like (PYL)/regulatory components of ABA receptor (RCAR) play a crucial role in ABA perception and signaling. However, little is known about the details regarding PYL family genes in Brassica juncea var. tumida. Here, 25 PYL family genes were identified in B. juncea var. tumida genome, including BjuPYL3, BjuPYL4s, BjuPYL5s, BjuPYL6s, BjuPYL7s, BjuPYL8s, BjuPYL10s, BjuPYL11s, and BjuPYL13. The results of phylogenic analysis and gene structure showed that the PYL family genes performed similar gene characteristics. By analyzing cis-elements in the promoters of those BjuPYLs, several hormone and stress related cis-elements were found. The results of gene expression analysis showed that the ABA receptor homologous genes were induced by abiotic and biotic stress. The tissue-specific gene expression patterns of BjuPYLs also suggested those genes might regulate the stem swelling during plant growth. These findings indicate that BjuPYLs are involved in plant response to stresses and organ development. This study provides valuable information for further functional investigations of PYL family genes in B. juncea var. tumida.

Transport inhibitor response 1/auxin signaling f-box proteins (TIR1/AFBs) play important roles in the process of plant growth and development as auxin receptors. To date, no information has been available about the characteristics of the TIR1/AFB gene family in Brassica juncea var. tumida. In this study, 18 TIR1/AFB genes were identified and could be clustered into six groups. The genes are located in 11 of 18 chromosomes in the genome of B. juncea var. tumida, and similar gene structures are found for each of those genes. Several cis-elements related to plant response to phytohormones, biotic stresses, and abiotic stresses are found in the promoter of BjuTIR1/AFB genes. The results of qPCR analysis show that most genes have differential patterns of expression among six tissues, with the expression levels of some of the genes repressed by salt stress treatment. Some of the genes are also responsive to pathogen Plasmodiophora brassicae treatment. This study provides valuable information for further studies as to the role of BjuTIR1/AFB genes in the regulation of plant growth, development, and response to abiotic stress.

Transport inhibitor response 1/auxin signaling f-box proteins (TIR1/AFBs) play important roles in the process of plant growth and development as auxin receptors. To date, no information has been available about the characteristics of the TIR1/AFB gene family in Brassica juncea var. tumida. In this study, 18 TIR1/AFB genes were identified and could be clustered into six groups. The genes are located in 11 of 18 chromosomes in the genome of B. juncea var. tumida, and similar gene structures are found for each of those genes. Several cis-elements related to plant response to phytohormones, biotic stresses, and abiotic stresses are found in the promoter of BjuTIR1/AFB genes. The results of qPCR analysis show that most genes have differential patterns of expression among six tissues, with the expression levels of some of the genes repressed by salt stress treatment. Some of the genes are also responsive to pathogen Plasmodiophora brassicae treatment. This study provides valuable information for further studies as to the role of BjuTIR1/AFB genes in the regulation of plant growth, development, and response to abiotic stress.

The phytohormone abscisic acid (ABA) is an essential part of the plant response to abiotic stressors such as drought. Upon the perception of ABA, pyrabactin resistance (PYR)/PYR1-like (PYL)/regulatory components of ABA receptor (RCAR) proteins interact with co-receptor protein phosphatase type 2Cs to permit activation Snf1-related protein kinase2 (SnRK2) kinases, which switch on ABA signaling by phosphorylating various target proteins. Thus, SnRK2 kinases are central regulators of ABA signaling. However, the mechanisms that regulate SnRK2 degradation remain elusive. Here, we show that SnRK2.3 is degradated by 26S proteasome system and ABA promotes its degradation. We found that SnRK2.3 interacts with AtPP2-B11 directly. AtPP2-B11 is an F-box protein that is part of a SKP1/Cullin/F-box E3 ubiquitin ligase complex that negatively regulates plant responses to ABA by specifically promoting the degradation of SnRK2.3. AtPP2-B11 was induced by ABA, and the knockdown of AtPP2-B11 expression markedly increased the ABA sensitivity of plants during seed germination and postgerminative development. Overexpression of AtPP2-B11 does not affect ABA sensitivity, but inhibits the ABA hypersensitive phenotypes of SnRK2.3 overexpression lines. These results reveal a novel mechanism through which AtPP2-B11 specifically degrades SnRK2.3 to attenuate ABA signaling and the abiotic stress response in Arabidopsis., Author summary The phytohormone ABA plays critical roles in both plant growth and development and the response to environmental stimuli. The SnRK2s are important components of the PYR/PYL-ABA-PP2C regulatory machine which activate a set of bZIP transcription factors and ion transporters. However, the regulation of SnRK2 turnover is poorly understood. In this work, we show that SnRK2s are degraded by 26S proteasome and ABA promotes SnRK2.3 degradation. We also show that an F-box protein, AtPP2-B11, interacts with Arabidopsis Skp1-like protein ASK1 and ASK2, is a component of a SKP1/Cullin/F-box E3 ubiquitin ligase complex. AtPP2-B11 interacts and regulates the degradation of SnRK2.3 specifically. AtPP2-B11 is induced by ABA and knockdown of AtPP2-B11 expression markedly increases ABA sensitivity of plants during seed germination and post-germinative development. Overexpression of AtPP2-B11 does not affect ABA sensitivity, but inhibits the ABA hypersensitive phenotypes of SnRK2.3 overexpression lines. These results reveal a mechanism through which AtPP2-B11 specifically degrades SnRK2.3 to attenuate the ABA signaling and plant responses to abiotic stress.

Alternative splicing (AS) of pre-mRNAs is one of the most important post-transcriptional regulations that enable a single gene to code for multiple proteins resulting in the biodiversity of proteins in eukaryotes. Recently, we have shown that an Arabidopsis thaliana RNA recognition motif (RRM)-containing protein RBM25 is a novel splicing factor to modulate plant response to ABA during seed germination and post-germination through regulating HAB1 pre-mRNA AS. Here we show that RBM25 is preferentially expressed in stomata and vascular tissues in Arabidopsis and is induced by ABA and abiotic stresses. Loss-of-function mutant is highly tolerant to drought and sensitive to salt stress. Bioinformatic analysis and expression assays reveal that Arabidopsis RBM25 is induced by multiple abiotic stresses, suggesting a crucial role of RBM25 in Arabidopsis responses to adverse environmental conditions. Furthermore, we provide a comprehensive characterization of the homologous genes of Arabidopsis RBM25 based on the latest plant genome sequences and public microarray databases. Fourteen homologous genes are identified in different plant species which show similar structure in gene and protein. Notably, the promoter analysis reveals that RBM25 homologs are likely controlled by the regulators involved in multiple plant growth and abiotic stresses, such as drought and unfavorable temperature. The comparative analysis of general and unique cis regulatory elements of the RBM25 homologs highlights the conserved and unique molecular processes that modulate plant response to abiotic stresses through RBM25-mediated alternative splicing.