QTL Mapping Combined With Bulked Segregant Analysis Identify SNP Markers Linked to Leaf Shape Traits in Pisum sativum Using SLAF Sequencing

Leaf shape is an important trait that influences the utilization rate of light, and affects quality and yield of pea (Pisum sativum). In the present study, a joint method of high-density genetic mapping using specific locus amplified fragment sequencing (SLAF-seq) and bulked segregant analysis (BSA) was applied to rapidly detect loci with leaf shape traits. A total of 7,146 polymorphic SLAFs containing 12,213 SNP markers were employed to construct a high-density genetic map for pea. We conducted quantitative trait locus (QTL) mapping on an F2 population to identify QTLs associated with leaf shape traits. Moreover, SLAF-BSA was conducted on the same F2 population to identify the single nucleotide polymorphism (SNP) markers linked to leaf shape in pea. Two QTLs (qLeaf_or-1, qLeaf_or-2) were mapped on linkage group 7 (LG7) for pea leaf shape. Through alignment of SLAF markers with Cicer arietinum, Medicago truncatula, and Glycine max, the pea LGs were assigned to their corresponding homologous chromosomal groups. The comparative genetic analysis showed that pea is more closely related to M. truncatula. Based on the sequencing results of two pools with different leaf shape, 179 associated markers were obtained after association analysis. The joint analysis of SLAF-seq and BSA showed that the QTLs obtained from mapping on a high-density genetic map are convincing due to the closely associated map region with the BSA results, which provided more potential markers related to leaf shape. Thus, the identified QTLs could be used in marker-assisted selection for pea breeding in the future. Our study revealed that joint analysis of QTL mapping on a high-density genetic map and BSA-seq is a cost-effective and accurate method to reveal genetic architecture of target traits in plant species without a reference genome

Estimation of Garden Chrysanthemum Crown Diameter Using Unmanned Aerial Vehicle (UAV)-Based RGB Imagery

Crown diameter is one of the crucial indicators for evaluating the adaptability, growth quality, and ornamental value of garden chrysanthemums. To accurately obtain crown diameter, this study employed an unmanned aerial vehicle (UAV) equipped with a RGB camera to capture orthorectified canopy images of 64 varieties of garden chrysanthemums at different growth stages. Three methods, namely RGB color space, hue-saturation-value (HSV) color space, and the mask region-based convolutional neural network (Mask R-CNN), were employed to estimate the crown diameter of garden chrysanthemums. The results revealed that the Mask R-CNN exhibited the best performance in crown diameter estimation (sample number = 2409, R2 = 0.9629, RMSE = 2.2949 cm). Following closely, the HSV color space-based model exhibited strong performance (sample number = 2409, R2 = 0.9465, RMSE = 3.4073 cm). Both of the first two methods were efficient in estimating crown diameter throughout the entire growth stage. In contrast, the RGB color space-based model exhibited slightly lower performance (sample number = 1065, R2 = 0.9011, RMSE = 3.3418 cm) and was only applicable during periods when the entire plant was predominantly green. These findings provide theoretical and technical support for utilizing UAV-based imagery to estimate the crown diameter of garden chrysanthemums

Molecular evolution and genome-wide analysis of the SBP-box family in cucumber (Cucumis sativas)

SQUAMOSA promoter binding protein (SBP)-box gene family encodes a group of transcription factors that play essential roles in plant development and stress responses. However, the SBP-box gene family has not been well characterized in cucumber (Cucumis sativas). In the present study, we identified 15 putative SBP-box genes (CuSBPs) distributing on 4 chromosomes of cucumber. Evolutionary analysis showed that the green plant SBP family originated from liverworts. Phylogenic analysis divided CuSBPs into 6 groups similar to those of Arabidopsis and rice. Intron–exon and motif structure within each group shared common features. Expression pattern analysis of transcriptional data for flowering demonstrated conserved CuSBPs function in vegetative-to-reproductive transition. Gene expression of cucumber leaves in response to powdery mildew showed that conserved CuSBPs function in regulatory pathways such as hormone regulation pathways. Moreover, codon bias analysis explained the mutation and selection pressure exerted on SBP-box genes. This study comprehensively characterized cucumber CuSBP gene family, which is likely to provide a foundation to explore the functions of CuSBPs for improving yield, quality and stress tolerance of cucumber in the future

Volatiles and Transcriptome Profiling Revealed the Formation of ‘Taro-like’ Aroma in the Leaf of Pumpkin (Cucurbita moschata)

‘Taro-like’ odor is an important economic trait of pumpkin species. The metabolic and molecular bases of this aromatic trait remain largely unexplored. Therefore, in this study, gas chromatography-mass spectrometry, GC-Olfactometry, and RNA-seq technology were used to illuminate the differential volatile compounds, the key volatile compounds, and differentially expressed genes (DEGs) in leaves from two pumpkin samples. Eight volatile compounds, including (E)-2-nonenal, 3-octanol, 2-ethyl-1-hexanol, 1-nonanol, α-terpineol, 2,3-pentanedione, caryophyllene, and 2-acetyl-1-pyrroline, were only detected in the sample with ‘taro-like’ aroma. Moreover, the variable importance in projection scores of all the above eight volatile compounds were >1.0 using PLS-DA analysis. The compounds 2-acetyl-1-pyrroline, 3-octanol, 1-nonanol, and (E)-3,7-dimethyl-2,6-octadienal were identified as the key contributors using GC-Olfactometry analysis. It was determined that 2-acetyl-1-pyrroline might play a significant role in ‘taro-like’ aroma. Furthermore, most of the differential volatile compounds were derived from fatty acids, and the DEGs were also involved in the pathways related to degradation, metabolism, and biosynthesis of fatty acids. Moreover, five genes involved in the accumulation of 2-acetyl-1-pyrroline showed differential expression, and their expression trends were consistent with 2-acetyl-1-pyrroline. This study offers the basis for further studies on the mechanism of ‘taro-like’ aroma in pumpkins

The Combination of Three Natural Compounds Effectively Prevented Lung Carcinogenesis by Optimal Wound Healing

<div><p>The tumor stroma has been described as “normal wound healing gone awry”. We explored whether the restoration of a wound healing-like microenvironment may facilitate tumor healing. Firstly, we screened three natural compounds (shikonin, notoginsenoside R1 and aconitine) from wound healing agents and evaluated the efficacies of wound healing microenvironment for limiting single agent-elicited carcinogenesis and two-stage carcinogenesis. The results showed that three compounds used alone could promote wound healing but had unfavorable efficacy to exert wound healing, and that the combination of three compounds made up treatment disadvantage of a single compound in wound healing and led to optimal wound healing. Although individual treatment with these agents may prevent cancer, they were not effective for the treatment of established tumors. However, combination treatment with these three compounds almost completely prevented urethane-induced lung carcinogenesis and reduced tumor burden. Different from previous studies, we found that urethane-induced lung carcinogenesis was associated with lung injury independent of pulmonary inflammation. LPS-induced pulmonary inflammation did not increase lung carcinogenesis, whereas decreased pulmonary inflammation by macrophage depletion promoted lung carcinogenesis. In addition, urethane damaged wound healing in skin excision wound model, reversed lung carcinogenic efficacy by the combination of three compounds was consistent with skin wound healing. Further, the combination of these three agents reduced the number of lung cancer stem cells (CSCs) by inducing cell differentiation, restoration of gap junction intercellular communication (GJIC) and blockade of the epithelial-to-mesenchymal transition (EMT). Our results suggest that restoration of a wound healing microenvironment represents an effective strategy for cancer prevention.</p></div

Urethane-induced lung carcinogenesis was associated with lung injury independent of pulmonary inflammation.

<p>(A) Urethane-induced lung carcinogenesis was promoted by BLM- or macrophage depletion-induced lung injury but was not affected by LPS-induced pulmonary inflammation. (B-D) LPS exposure, BLM exposure and macrophage depletion reversed carcinogenic preventive efficacy of single compound but had slight effect on combined efficacy shown as lung tumor incidence, lung tumor number and lung weight, respectively. The results are presented as mean±SE (n = 20/group). *<i>p</i> < 0.05, **<i>p</i> < 0.01, vs control group.</p

The screened three wound healing agents desereased lung tumor overall volume and did not negatively impact health or significantly affect the body weights of mice.

<p>(A) Three wound healing agents desereased lung tumor overall volume. (B-D) Three wound healing agents did not negatively impact health or significantly affect the body weights of mice. The results are presented as mean±SE (n = 10/group). *<i>p</i> < 0.05, **<i>p</i> < 0.01, vs control group.</p

The pharmacological properties of screened three wound healing agents.

<p>(A) Screened three compounds promoted wound closure in a skin excision wound model. (B) Notoginsenoside R1 and aconitine increased blood flow perfusion on laser speckle imaging. (C) Shikonin exerted anti-inflammatory efficacy in the TPA-induced ear edema model. (D) Notoginsenoside R1 and aconitine promoted macrophage phagocytosis of zymosan. The results are presented as mean±SE (n = 10/group). ** <i>p</i> < 0.01, vs. control group.</p

Gingerol Reverses the Cancer-Promoting Effect of Capsaicin by Increased TRPV1 Level in a Urethane-Induced Lung Carcinogenic Model

Both gingerol and capsaicin are agonists of TRPV1, which can negatively control tumor progression. This study observed the long-term effects of oral administration of 6-gingerol alone or in combination with capsaicin for 20 weeks in a urethane-induced lung carcinogenic model. We showed that lung carcinoma incidence and multiplicity were 70% and 21.2 ± 3.6, respectively, in the control versus 100% and 35.6 ± 5.2 in the capsaicin group (<i>P</i> < 0.01) and 50% and 10.8 ± 3.1 in the 6-gingerol group (<i>P</i> < 0.01). The combination of 6-gingerol and capsaicin reversed the cancer-promoting effect of capsaicin (carcinoma incidence of 100% versus 20% and multiplicity of 35.6 ± 5.2 versus 4.7 ± 2.3; <i>P</i> < 0.001). The cancer-promoting effect of capsaicin was due to increased epidermal growth-factor receptor (EGFR) level by decreased transient receptor potential vanilloid type-1 (TRPV1) level (<i>P</i> < 0.01) . The capsaicin-decreased EGFR level subsequently reduced levels of nuclear factor-κB (NF-κB) and cyclin D1 that favored enhanced lung epithelial proliferation and epithelial–mesenchymal transition (EMT) during lung carcinogenesis (<i>P</i> < 0.01). In contrast, 6-gingerol promoted TRPV1 level and drastically decreased the levels of EGFR, NF-κB, and cyclin D1 that favored reduced lung epithelial proliferation and EMT (<i>P</i> < 0.01). This study provides valuable information for the long-term consumption of chili-pepper-rich diets to decrease the risk of cancer development

The wound healing microenvironment prevented lung cell malignant transformation.

<p>(A) The combination of three compounds reduced the population expressing stem cell markers or EMT markers examined by flow cytometry and in A549 cells. (B) The combination of three compounds decreased A549 cell self-renew shown as the number of tumor spheres and soft agar colonies. (C) The combination of three compounds decreased the population expressing EMT markers examined by flow cytometry in urethane-treated BEAS-2B cells. The results are presented as mean±SE (n = 5/group) **<i>p</i> < 0.01 <i>vs</i> control group.</p