Identification of a sugarcane bacilliform virus promoter that is activated by drought stress in plants.

Sugarcane (Saccharum spp.) is an important sugar and biofuel crop in the world. It is frequently subjected to drought stress, thus causing considerable economic losses. Transgenic technology is an effective breeding approach to improve sugarcane tolerance to drought using drought-inducible promoter(s) to activate drought-resistance gene(s). In this study, six different promoters were cloned from sugarcane bacilliform virus (SCBV) genotypes exhibiting high genetic diversity. In ß-glucuronidase (GUS) assays, expression of one of these promoters (PSCBV-YZ2060) is similar to the one driven by the CaMV 35S promoter and >90% higher compared to the other cloned promoters and Ubi1. Three SCBV promoters (PSCBV-YZ2060, PSCBV-TX, and PSCBV-CHN2) function as drought-induced promoters in transgenic Arabidopsis plants. In Arabidopsis, GUS activity driven by promoter PSCBV-YZ2060 is also upregulated by abscisic acid (ABA) and is 2.2-5.5-fold higher when compared to the same activity of two plant native promoters (PScRD29A from sugarcane and PAtRD29A from Arabidopsis). Mutation analysis revealed that a putative promoter region 1 (PPR1) and two ABA response elements (ABREs) are required in promoter PSCBV-YZ2060 to confer drought stress response and ABA induction. Yeast one-hybrid and electrophoretic mobility shift assays uncovered that transcription factors ScbZIP72 from sugarcane and AREB1 from Arabidopsis bind with two ABREs of promoter PSCBV-YZ2060. After ABA treatment or drought stress, the expression levels of endogenous ScbZIP72 and heterologous GUS are significantly increased in PSCBV-YZ2060:GUS transgenic sugarcane plants. Consequently, promoter PSCBV-YZ2060 is a possible alternative promoter for genetic engineering of drought-resistant transgenic crops such as sugarcane.

Influence of Planting Density on Sweet Potato Storage Root Formation by Regulating Carbohydrate and Lignin Metabolism.

An appropriate planting density could realize the maximum yield potential of crops, but the mechanism of sweet potato storage root formation in response to planting density is still rarely investigated. Four planting densities, namely D15, D20, D25, and D30, were set for 2-year and two-site field experiments to investigate the carbohydrate and lignin metabolism in potential storage roots and its relationship with the storage root number, yield, and commercial characteristics at the harvest period. The results showed that an appropriate planting density (D20 treatment) stimulated cambium cell differentiation, which increased carbohydrate accumulation and inhibited lignin biosynthesis in potential storage roots. At canopy closure, the D20 treatment produced more storage roots, particularly developing ones. It increased the yield by 10.18-19.73% compared with the control D25 treatment and improved the commercial features by decreasing the storage root length/diameter ratio and increasing the storage root weight uniformity. This study provides a theoretical basis for the high-value production of sweet potato.

The Regulatory Network of Sweet Corn (Zea mays L.) Seedlings under Heat Stress Revealed by Transcriptome and Metabolome Analysis.

Heat stress is an increasingly significant abiotic stress factor affecting crop yield and quality. This study aims to uncover the regulatory mechanism of sweet corn response to heat stress by integrating transcriptome and metabolome analyses of seedlings exposed to normal (25 °C) or high temperature (42 °C). The transcriptome results revealed numerous pathways affected by heat stress, especially those related to phenylpropanoid processes and photosynthesis, with 102 and 107 differentially expressed genes (DEGs) identified, respectively, and mostly down-regulated in expression. The metabolome results showed that 12 or 24 h of heat stress significantly affected the abundance of metabolites, with 61 metabolites detected after 12 h and 111 after 24 h, of which 42 metabolites were detected at both time points, including various alkaloids and flavonoids. Scopoletin-7-o-glucoside (scopolin), 3-indolepropionic acid, acetryptine, 5,7-dihydroxy-3',4',5'-trimethoxyflavone, and 5,6,7,4'-tetramethoxyflavanone expression levels were mostly up-regulated. A regulatory network was built by analyzing the correlations between gene modules and metabolites, and four hub genes in sweet corn seedlings under heat stress were identified: RNA-dependent RNA polymerase 2 (RDR2), UDP-glucosyltransferase 73C5 (UGT73C5), LOC103633555, and CTC-interacting domain 7 (CID7). These results provide a foundation for improving sweet corn development through biological intervention or genome-level modulation.

First report of Capsicum chlorosis virus naturally infecting Ageratum conyzoides in China.

Capsicum chlorosis virus (CaCV; family Tospoviridae, genus Orthotospovirus) was first reported to infect capsicum (Capsicum annuum) and tomato (Solanum lycopersicum) in Australia in 2002 (McMichael et al., 2002). Subsequently, its infection was detected in different plants including waxflower (Hoya calycina Schlecter) in the United States (Melzer et al. 2014), peanut (Arachis hypogaea) in India (Vijayalakshmi et al. 2016), and spider lily (Hymenocallis americana) (Huang et al. 2017), Chilli pepper (Capsicum annuum) (Zheng et al. 2020), and Feiji cao (Chromolaena odorata) (Chen et al. 2022) in China. Ageratum conyzoides L. (commonly known as goat weed, family Asteraceae) is a natural weed in crop fields distributed in subtropical and tropical areas and a reservoir host of numerous plant pathogens (She et al. 2013). In April 2022, we observed that 90% of plants of A. conyzoides in maize fields in Sanya, Hainan province, China, exhibited typical virus-like symptoms of vein yellowing, leaf chlorosis, and distortion (Fig. S1 A-C). Total RNA was extracted from one symptomatic leaf of A. conyzoides. Small RNA libraries were constructed using the small RNA Sample Pre Kit (Illumina, San Diego, USA) for sequencing with an Illumina Novaseq 6000 platform (Biomarker Technologies Corporation, Beijing, China). A total 15,848,189 clean reads were obtained after removing low-quality reads. Quality-controlled qualified reads were assembled into contigs using Velvet 1.0.5 software with a k-mer value of 17. One hundred contigs shared nucleotide identity ranging from 85.7% to 100% with the CaCV using BLASTn searches online (https://blast.ncbi.nlm.nih.gov/Blast.cgi?). Numerous contigs (45, 34, and 21) obtained in this study were mapped to the L, M, and S RNA segments of the CaCV-Hainan isolate (GenBank accession no. KX078565- KX078567) from spider lily (Hymenocallis americana) in Hainan province, China, respectively. The full-length of L, M, and S RNA segments of CaCV-AC were determined to be 8,913, 4,841, and 3,629 bp, respectively (GenBank accession no. OQ597167- OQ597169). Furthermore, five symptomatic leaf samples were tested to be positive for CaCV using a CaCV enzyme-linked immunosorbent assay (ELISA) kit (MEIMIAN, Jiangsu, China) (Fig. S1-D). Total RNA from these leaves was amplified by RT-PCR with two sets of primer pairs. Primers CaCV-F (5'-ACTTTCCATCAACCTCTGT-3') and CaCV-R (5'-GTTATGGCCATATTTCCCT-3') were used for the amplification of 828 bp fragment from nucleocapsid protein (NP) on CaCV S RNA. While another, primers gL3637 (5'-CCTTTAACAGTDGAAACAT-3') and gL4435c (5'-CATDGCRCAAGARTGRTARACAGA-3') were used for the amplification of 816 bp fragment from RNA-dependent RNA polymerase (RdRP) on CaCV L RNA (Fig. S1-E and -F) (Basavaraj et al. 2020). These amplicons were cloned into the pCE2 TA/Blunt-Zero vector (Vazyme, Nanjing, China) and three independent positive colonies of Escherichia coli DH5α carrying each viral amplicon were sequenced. These sequences were deposited in the GenBank database under accession nos. OP616700-OP616709. Pairwise sequence comparison revealed that nucleotide sequences of NP and RdRP genes of the five CaCV isolates shared 99.5% (812 bp out of 828 bp) and 99.4% (799 bp out of 816 bp) nucleotide identities, respectively. They showed 86.2-99.2% and 86.5-99.1% nucleotide identities with corresponding nucleotide sequences of other CaCV isolates derived from GenBank database, respectively. The highest nucleotide sequence identity (99%) of the CaCV isolates obtained in the study was observed with the CaCV-Hainan isolate. Phylogenetic analysis based on NP amino acid demonstrated that six CaCV isolates (this study = 5 and NCBI database = 1) clustered into one distinct clade (Fig. S2). Our data confirmed for the first time the presence of CaCV naturally infecting A. conyzoides plant in China, which enriches information on the host range and will be helpful for disease management.

Genome-wide identification and expression analysis of the cyclic nucleotide-gated ion channel (CNGC) gene family in Saccharum spontaneum.

BACKGROUND: Cyclic nucleotide-gated ion channels (CNGCs) are nonselective cation channels that are ubiquitous in eukaryotic organisms. As Ca2+ channels, some CNGCs have also proven to be K+-permeable and involved in plant development and responses to environmental stimuli. Sugarcane is an important sugar and energy crop worldwide. However, reports on CNGC genes in sugarcane are limited. RESULTS: In this study, 16 CNGC genes and their alleles were identified from Saccharum spontaneum and classified into 5 groups based on phylogenetic analysis. Investigation of gene duplication and syntenic relationships between S. spontaneum and both rice and Arabidopsis demonstrated that the CNGC gene family in S. spontaneum expanded primarily by segmental duplication events. Many SsCNGCs showed variable expression during growth and development as well as in tissues, suggesting functional divergence. Light-responsive cis-acting elements were discovered in the promoters of all the identified SsCNGCs, and the expression of most of the SsCNGCs showed a diurnal rhythm. In sugarcane, the expression of some SsCNGCs was regulated by low-K+ treatment. Notably, SsCNGC13 may be involved in both sugarcane development and its response to environmental stimuli, including response to low-K+ stress. CONCLUSION: This study identified the CNGC genes in S. spontaneum and provided insights into the transcriptional regulation of these SsCNGCs during development, circadian rhythm and under low-K+ stress. These findings lay a theoretical foundation for future investigations of the CNGC gene family in sugarcane.

α-Cyperone ameliorates depression in mammary gland hyperplasia and chronic unpredictable mild stress rat by regulating hormone, inflammation, and oxidative stress.

BACKGROUND: Hyperplasia of mammary gland (HMG) is caused by endocrine disorders, and patients are prone to anxiety and depression. α-Cyperone has a variety of pharmacological activities including antidepressant. The purpose of this study was to explore the effect and its possible mechanism of α-Cyperone on HMG-associated depression rats. METHODS: The depression model was constructed using chronic unpredictable mild stress (CUMS), while the HMG model was induced by estrogen, with or without α-Cyperone intervention. The effect of α-Cyperone on the depression-like phenotype of model rats was measured by sucrose preference test (SPT), forced swim test (FST), and open field test (OFT). Dendritic spines density in ventral medial prefrontal cortex (vmPFC) neurons was evaluated by Golgi staining. The second pair of nipple height, diameter, organ index, and oxidative stress-related factors were analyzed. Serum sex hormone concentration, histopathological changes, inflammatory factor expression, and p65 were evaluated by enzyme-linked immunosorbent assay (ELISA), hematoxylin and eosin (HE) staining, real-time quantitative PCR and western blot, respectively. RESULTS: The sucrose preference rate, dendritic spine density decreased, and immobility time increased in CUMS rats; α-Cyperone reversed the effect of CUMS on depression-like behavior and dendritic spine density in rats. α-Cyperone reduced nipple height and diameter, uterine index, estradiol concentration, increased ovary, thymus, spleen index, progesterone, and testosterone concentration, relieved pathological damage, oxidative stress, depression-like behavior, and inflammatory reaction in HMG combine CUMS rats. In addition, α-Cyperone inhibited the phosphorylation of p65 in HMG and CUMS rats. CONCLUSIONS: α-Cyperone has an effective therapeutic effect on HMG combined with CUMS rats.

First Report of Puccinia engleriana Causing Leaf Rust of Tabernaemontana bufalina in Hainan, China.

Tabernaemontana bufalina Lour. is extensively cultivated as an ornamental plant in Hainan, Guangdong, and other regions of southern China. In January 2020, we observed a rust disease on T. bufalina leaves in Sanya (18.15。N and 109.30。E) Hainan, China, and the rust occurred all year-round. In the early stage of rust, yellow chlorotic spots appeared, and then uredinia on the abaxial leaf surface became visible. Uredinia (approximately 200-700 µm in diameter) were mostly yellowish-brown in color, solitary, and irregularly scattered. In the late stage of the disease, spots were connected into lesions, and eventually, the whole leaf became severely chlorotic. Urediniospores were light brown, subglobose, measured 25-30 µm × 20-25 µm. They had two pores and were echinulate with spines spaced 2-5 µm. The teliospores were naked, scattered, or aggregated on severely infected leaves. They were two-celled, measured 33-40 µm × 25-30 µm, elliptic, dark brown, and covered with tiny spines. The teliospores had a colorless pedicel at one end which was approximately 28-34 µm long and enlarged at the lower part. The morphological characteristics of the spores were consistent with the descriptions of Puccinia engleriana Henn. (Hennings 1905). In China, P. engleriana was first identified on the leaves of Tabernaemontana divaricata (L.) in Yunnan province, and recorded as new to China in 2012 (Zhuang 2012). Untill now, no leaf rust caused by P. engleriana has been reported in Hainan. Urediniospores were collected and DNA was extracted using a Quick-DNA extraction Kit (TIANGEN Biotech, Beijing, China). The nuclear large subunit (28S) region of the ribosomal DNA repeat was amplified with primers Rust28SF (Aime et al. 2018) and LR5 (Vilgalys and Hester 1990) following the protocol of Aime and McTaggart (2021). The length of the large subunit sequence was 1,010 bp. When searched the GenBank database, the sequence showed 97.07% homology to the large subunit ribosomal RNA gene (Sequence ID: MW147048.1) of P. engleriana, and 92.5% similarity with 18S ribosomal RNA gene (Sequence ID: KM249855.1) of P. hemerocallidis. This result was consistent with the morphological identification. As for the 3% difference in large subunit ribosomal RNA gene, it was speculated that it may be related to the differences of geographical distribution and host plants, as the reference P. engleriana was obtained from Tabernaemontana orientalis in Australia (Aime and McTaggart 2021). The large subunit sequence was submitted into the GenBank database, with accession No. MZ314895. T. bufalina cutting seedlings with 4 available leaves were used in the Koch's postulate test. These seedlings were planted in a greenhouse with a 14 h/10 h light/dark photoperiod at 28°C and 65% humidity. The urediniospores suspension (5107/ml in 0.05% Tween 20 solution) was sprayed on 6 healthy seedlings and other 6 seedlings were sprayed with 0.05% Tween 20 solution as a negative control. Two weeks after inoculation, leaf chlorosis and yellowish uredinia were observed on the inoculated seedlings, whereas the non-inoculated seedlings stayed healthy. To our knowledge, this is the first report of P. engleriana causing leaf rust on T. bufalina in Hainan province. This report will provide the reference for future investigation of T. bufalina leaf rust, and for further improvement on the knowledge of the geographical distribution of P. engleriana in China.

Genome-wide characterization of cys-tathionine-ß-synthase domain-containing proteins in sugarcane reveals their role in defense responses under multiple stressors.

Cys-tathionine-ß-synthase (CBS) domain-containing proteins (CDCPs) are essential for regulating plant responses to various biotic and abiotic stressors. This study describes the systematic identification and characterization of CDCP family genes in Saccharum spontaneum. A total of 95 SsCDCP genes and eight phylogenetic groups were identified that were distributed over 29 chromosomes of the AP85-441 genome. Most (78/95) SsCDCPs underwent fragment duplication events, and 64 gene pairs were located in synteny blocks. Expression profiling of nine ShCDCPs was also carried out in the Saccharum spp. cultivars ROC22 and MT11-611 that are resistant and susceptible to red stripe, respectively, in response to: (i) Infection by the bacterial pathogen Acidovorax avenue subsp. avenae (Aaa); (ii) abiotic stressors (drought and salinity); and (iii) exogenous salicylic acid (SA) treatment. Members of one gene pair (ShCBSD-PB1-5A and ShCBSD-PB1-7A-1) with a fragment duplication event acted as negative regulators in sugarcane under four stresses, as supported by the significantly decreased expression levels of ShCBSD-PB1-5A (23-83%) and ShCBSD-PB1-7A-1 (15-75%) at all-time points, suggesting that they have functional redundancy. Genes in another pair, ShCBS-4C and ShCBS-4D-1, which have a fragment duplication event, play opposing regulatory roles in sugarcane exposed to multiple stresses, particularly Aaa and NaCl treatments. ShCBS-4C expression was significantly decreased by 32-77%, but ShCBS-4D-1 expression was dramatically upregulated by 1.2-6.2-fold in response to Aaa treatment of both cultivars across all-time points. This result suggested that both genes exhibited functional divergence. Meanwhile, the expression of SsCBSDCBS-5A was significantly upregulated in ROC22 by 1.4-4.6-fold in response to the four stressors. These findings provide important clues for further elucidating the function of ShCDCP genes in sugarcane responding to a diverse range of stresses.

Identification and Expression Profiling of WRKY Family Genes in Sugarcane in Response to Bacterial Pathogen Infection and Nitrogen Implantation Dosage.

WRKY transcription factors (TFs) are essential players in different signaling cascades and regulatory networks involved in defense responses to various stressors. This study systematically analyzed and characterized WRKY family genes in the Saccharum spp. hybrid R570 and their expression in two sugarcane cultivars LCP85-384 (resistant to leaf scald) and ROC20 (susceptible to leaf scald) in response to bacterial pathogen infection and nitrogen implantation dosage. A total of 53 ShWRKY genes with 66 alleles were systematically identified in R570 based on the query sequence SsWRKY in S. spontaneum AP85-441. All ShRWKY alleles were further classified into four groups with 11 (16.7%) genes in group I, 36 (54.5%) genes in group II, 18 (27.3%) genes in group III, and 1 (1.5%) gene in group IV. Among them, 4 and 11 ShWRKY gene pairs displayed tandem and segmental duplication events, respectively. The ShWRKY genes exhibited conserved DNA-binding domains, which were accompanied by variations in introns, exons, and motifs. RT-qPCR analysis of two sugarcane cultivars triggered by Xanthomonas albilineans (Xa) revealed that four genes, ShWRKY13-2/39-1/49-3/125-3, exhibited significant upregulation in leaf scald-resistant LCP85-384. These WRKY genes were downregulated or unchanged in ROC20 at 24-72 h post-inoculation, suggesting that they play an important role in defense responses to Xa infection. Most of the 12 tested ShWRKYs, ShWRKY22-1/49-3/52-1 in particular, functioned as negative regulators in the two cultivars in response to a range of nitrogen (N) implantation doses. A total of 11 ShWRKY proteins were predicted to interact with each other. ShWRKY43 and ShWRKY49-3 are predicted to play core roles in the interaction network, as indicated by their interaction with six other ShWRKY proteins. Our results provide important candidate gene resources for the genetic improvement of sugarcane and lay the foundation for further functional characterization of ShWRKY genes in response to coupling effects of Xa infection and different N levels.

Chromosome Painting Provides Insights Into the Genome Structure and Evolution of Sugarcane.

The genus Saccharum is composed of species with high polyploidy and highly varied chromosome numbers, laying a challenge for uncovering its genomic structure and evolution. We developed a chromosome 2 painting (CP2) probe by designing oligonucleotides covering chromosome 2 of Saccharum spontaneum (2n = 8x = 64). Fluorescence in situ hybridization (FISH) using this CP2 probe revealed six types of ploidies from twenty S. spontaneum clones, including 6x, 8x, 10x, 11x, 12x, and 13x clones. The finding of S. spontaneum clones with uneven of ploid suggested that certain S. spontaneum clones come from hybridization. It renews our knowledge that S. spontaneum is derived from autopolyploidization. Combined with a S. spontaneum-specific probe, chromosome 2-derived chromosome or fragments from either S. spontaneum or Saccharum officinarum can be identified in sugarcane modern cultivars. We revealed unexpected high level of interspecific recombination from introgressive S. spontaneum chromosomes (>50.0%) in cultivars ROC22 and ZZ1, indicating frequent chromosome exchange in cultivars. Intriguingly, we observed interspecific recombination recurring among either homoeologous or non-homoeologous chromosomes in sugarcane cultivars. These results demonstrated that chromosome painting FISH is a powerful tool in the genome dissection of sugarcane and provide new insights into the genome structure and evolution of the complex genus Saccharum.

Chromosome behavior during meiosis in pollen mother cells from Saccharum officinarum × Erianthus arundinaceus F1 hybrids.

BACKGROUND: In recent years, sugarcane has attracted increasing attention as an energy crop. Wild resources are widely used to improve the narrow genetic base of sugarcane. However, the infertility of F1 hybrids between Saccharum officinarum (S. officinarum) and Erianthus arundinaceus (E. arundinaceus) has hindered sugarcane breeding efforts. To discover the cause of this infertility, we studied the hybridization process from a cytological perspective. RESULTS: We examined the meiotic process of pollen mother cells (PMCs) in three F1 hybrids between S. officinarum and E. arundinaceus. Cytological analysis showed that the male parents, Hainan 92-77 and Hainan 92-105, had normal meiosis. However, the meiosis process in F1 hybrids showed various abnormal phenomena, including lagging chromosomes, micronuclei, uneven segregation, chromosome bridges, and inability to form cell plates. Genomic in situ hybridization (GISH) showed unequal chromatin distribution during cell division. Interestingly, 96.70% of lagging chromosomes were from E. arundinaceus. Furthermore, fluorescence in situ hybridization (FISH) was performed using 45S rDNA and 5S rDNA as probes. Either 45S rDNA or 5S rDNA sites were lost during abnormal meiosis, and results of unequal chromosomal separation were also clearly observed in tetrads. CONCLUSIONS: Using cytogenetic analysis, a large number of meiotic abnormalities were observed in F1. GISH further confirmed that 96.70% of the lagging chromosomes were from E. arundinaceus. Chromosome loss was found by further investigation of repeat sequences. Our findings provide insight into sugarcane chromosome inheritance to aid innovation and utilization in sugarcane germplasm resources.

Salt Stress Modulates the Landscape of Transcriptome and Alternative Splicing in Date Palm (Phoenix dactylifera L.).

Date palm regards as a valuable genomic resource for exploring the tolerance genes due to its ability to survive under the sever condition. Although a large number of differentiated genes were identified in date palm responding to salt stress, the genome-wide study of alternative splicing (AS) landscape under salt stress conditions remains unknown. In the current study, we identified the stress-related genes through transcriptomic analysis to characterize their function under salt. A total of 17,169 genes were differentially expressed under salt stress conditions. Gene expression analysis confirmed that the salt overly sensitive (SOS) pathway genes, such as PdSOS2;1, PdSOS2;2, PdSOS4, PdSOS5, and PdCIPK11 were involved in the regulation of salt response in date palm, which is consistent with the physiological analysis that high salinity affected the Na+/K+ homeostasis and amino acid profile of date palm resulted in the inhibition of plant growth. Interestingly, the pathway of "spliceosome" was enriched in the category of upregulation, indicating their potential role of AS in date palm response to salt stress. Expectedly, many differentially alternative splicing (DAS) events were found under salt stress conditions, and some splicing factors, such as PdRS40, PdRSZ21, PdSR45a, and PdU2Af genes were abnormally spliced under salt, suggesting that AS-related proteins might participated in regulating the salt stress pathway. Moreover, the number of differentially DAS-specific genes was gradually decreased, while the number of differentially expressed gene (DEG)-specific genes was increased with prolonged salt stress treatment, suggesting that AS and gene expression could be distinctively regulated in response to salt stress. Therefore, our study highlighted the pivotal role of AS in the regulation of salt stress and provided novel insights for enhancing the resistance to salt in date palm.

Molecular and Toxicity Analyses of White Granulated Sugar and Other Processing Products Derived From Transgenic Sugarcane.

This study aimed to prepare the sugar industry for the possible introduction of genetically modified (GM) sugarcane and derived retail sugar products and to address several potential public concerns regarding the characteristics and safety of these products. GM sugarcane lines with integrated Cry1Ab and EPSPS foreign genes were used for GM sugar production. Traditional PCR, real-time fluorescent quantitative PCR (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA) were performed in analyzing leaves, stems, and other derived materials during sugar production, such as fibers, clarified juices, filter mud, syrups, molasses, and final GM sugar product. The toxicity of GM sugar was examined with a feeding bioassay using Helicoverpa armigera larvae. PCR and RT-qPCR results showed that the leaves, stems, fibers, juices, syrups, filter mud, molasses, and white granulated sugar from GM sugarcane can be distinguished from those derived from non-GM sugarcane. The RT-qPCR detection method using short amplified product primers was more accurate than the traditional PCR method. Molecular analysis results indicated that trace amounts of DNA residues remain in GM sugar, and thus it can be accurately characterized using molecular analysis methods. ELISA results showed that only the leaves, stems, fibers, and juices sampled from the GM sugarcane differed from those derived from the non-GM sugarcane, indicating that filter mud, syrup, molasses, and white sugar did not contain detectable Cry1Ab and EPSPS proteins. Toxicity analysis showed that the GM sugar was not toxic to the H. armigera larvae. The final results showed that the GM sugar had no active proteins despite containing trace amounts of DNA residues. This finding will help to pave the way for the commercialization of GM sugarcane and production of GM sugar.

Association between vitamin D deficiency and fragility fractures in Chinese elderly patients: a cross-sectional study.

BACKGROUND: Vitamin D deficiency can lead to osteoporosis and increases the risk of fractures. Vitamin D deficiency is prevalent in Asian populations, however, research focusing on the association between vitamin D deficiency and osteoporotic hip fractures, particularly in Chinese populations is scarce. The aim of this study was to explore the relationship between vitamin D deficiency and osteoporotic hip fractures in elderly Chinese patients. METHODS: This cross-sectional study recruited 60 patients (aged 65 years and over) who had hip fractures. Serum 25-hydroxyvitamin D (25OHD) levels were examined using an electrochemiluminescence immunoassay. The patients were classified into two groups based on their bone mineral density (BMD); subjects with osteoporosis (BMD t value ≤-2.5) and individuals without osteoporosis (BMD t value ≥-1.0). Serum 25OHD was further analyzed in these two groups. RESULTS: Across all of the patients with hip fractures, approximately 10% showed vitamin D deficiency, and a further 53.33% showed vitamin D. insufficiency. Furthermore, of the patients with hip fractures, those with osteoporosis had significantly lower levels of serum 25OHD (25.43±6.35 ng/mL) compared to those patients without osteoporosis (30.70±7.17 ng/mL). The incidence of vitamin D insufficiency (66.67%) and deficiency (16.67%) was higher in the patients with osteoporosis than in those without osteoporosis (insufficiency 44.44% and deficiency 5.56%, respectively). CONCLUSIONS: Our study confirmed a high prevalence of vitamin D insufficiency in elderly patients with hip fractures in China. Our data suggests that vitamin D plays an important role in the occurrence of hip fractures in these elderly patients, and especially where patients also suffer from osteoporosis.

SARI attenuates colon inflammation by promoting STAT1 degradation in intestinal epithelial cells.

SARI functions as a suppressor of colon cancer and predicts survival of colon cancer patients, but its role in regulating colitis has not been characterized. Here we show that SARI-/- mice were highly susceptible to colitis, which was associated with enhanced macrophage infiltration and inflammatory cytokine production. Bone marrow reconstitution experiments demonstrated that disease susceptibility was not dependent on the deficiency of SARI in the immune compartment but on the protective role of SARI in the intestinal epithelial cells (IECs). Furthermore, SARI deficiency enhanced Chemokine (C-C motif) Ligand 2 (CCL2) production and knockout of CCR2 blocks the promoting role of SARI deficiency on colitis. Mechanistically, SARI directly targets and promotes signal transducer and activator of transcription 1 (STAT1) degradation in IECs, followed by persistent inactivation of the STAT1/CCL2 transcription complex. In summary, SARI attenuated colitis in mice by impairing colitis-dependent STAT1/CCL2 transcriptional activation in IECs and macrophages recruitment in colon tissue.

Chromosome transmission in BC4 progenies of intergeneric hybrids between Saccharum spp. and Erianthus arundinaceus (Retz.) Jeswiet.

Intergeneric hybrids between Saccharum spp. and Erianthus arundinaceus and clones derived from these hybrids and backcrosses to Saccharum spp. were used to study the transmission of E. arundinaceus chromosomes by genomic in situ hybridization (GISH). True hybrid progenies were precisely identified using PCR with a primer pair, AGRP52/53. The results showed that AGRP52/53 was an E. arundinaceus-specific primer pair and could be used as molecular marker to assist breeding. EaHN92, a 364 bp E. arundinaceus-specific tandem repeat satellite DNA sequence, was cloned from the E. arundinaceus clone HN92-105 with AGRP52/53, and was localized on sub-telomeric regions of all E. arundinaceus chromosomes. YCE06-61, a BC3 progeny, had 7 E. arundinaceus chromosomes and its progenies had approximately 1-6 E. arundinaceus chromosomes. The number of E. arundinaceus chromosomes in true hybrids appeared as Gaussian distribution in 3 cross combinations. In addition, GISH detected intergeneric chromosome translocation in a few progenies. Hence, screening clones containing approximately 1-2 E. arundinaceus chromosomes without translocation could be used for sorting and sequencing E. arundinaceus chromosomes. This study provides a method for breeders to select true hybrid progenies between Saccharum spp. and E. arundinaceus, which will accelerate this intergeneric hybridization breeding.

Genetic diversity and population structure analysis of Saccharum and Erianthus genera using microsatellite (SSR) markers.

In order to understand the genetic diversity and structure within and between the genera of Saccharum and Erianthus, 79 accessions from five species (S. officinarum, S. spontaneum, S. robustum, S. barberi, S. sinense), six accessions of E. arundinaceus, and 30 Saccharum spp. hybrids were analyzed using 21 pairs of fluorescence-labeled highly poloymorphic SSR primers and a capillary electrophoresis (CE) detection system. A total of 167 polymorphic SSR alleles were identified by CE with a mean value of polymorphic information content (PIC) of 0.92. Genetic diversity parameters among these 115 accessions revealed that Saccharum spp. hybrids were more diverse than those of Saccharum and Erianthus species. Based on the SSR data, the 115 accessions were classified into seven main phylogenetic groups, which corresponded to the Saccharum and Erianthus genera through phylogenetic analysis and principle component analysis (PCA). We propose that seven core SSR primer pairs, namely, SMC31CUQ, SMC336BS, SMC597CS, SMC703BS, SMC24DUQ, mSSCIR3, and mSSCIR43, may have a wide appicability in genotype identification of Saccharum species and Saccharum spp. hybrids. Thus, the information from this study contibites to manage sugarcane genetic resources.

1,25-Dihydroxyvitamin D3 attenuates disease severity and induces synoviocyte apoptosis in a concentration-dependent manner in rats with adjuvant-induced arthritis by inactivating the NF-κB signaling pathway.

An aggressive proliferation of synoviocytes is the hallmark of rheumatoid arthritis (RA). Emerging evidence shows that inhibiting the NF-κB signaling pathway with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] may be a therapeutic approach for controlling inflammatory diseases. In this study, we demonstrated the protective effects of three different 1,25(OH)2D3 concentration on adjuvant-induced arthritis (AA) rats through the NF-κB signaling pathway and their pro-apoptotic roles in cultured adjuvant-induced arthritis synoviocytes (AIASs). AA rats were prepared by injecting complete Freund's adjuvant and independently given daily intraperitoneal injection of 1,25(OH)2D3 at concentrations of 50, 100, and 300 ng/day/kg. Subsequently, AIASs were isolated from the inflamed joints of AA rats to test the effects of 1,25(OH)2D3 on AIASs in vitro. Intraperitoneal injection of 1,25-(OH)2D3 was found to induce a concentration- and time-dependent improvement in relieving the symptoms of AA. We found an increased paw withdrawal thermal latency (PWTL) in the affected paw of AA rats as the concentration of 1,25-(OH)2D3 increased. 1,25-(OH)2D3 treatment reduced levels of inflammatory factors in synovial tissues of AA rats. In the case of cultured AIASs, 1,25-(OH)2D3 was shown to inhibit cell proliferation and induce cell apoptosis in a concentration-dependent manner. Additionally, 1,25-(OH)2D3 inhibited the activation of the NF-κB signaling pathway. In conclusion, our study provides evidence emphasizing that 1,25(OH)2D3 has the potential to attenuate disease severity in RA potentially due to its contributory role in synoviocyte proliferation and apoptosis. The protective role of 1,25(OH)2D3 against RA depends on the NF-κB signaling pathway.

Characterization of chromosome composition of sugarcane in nobilization by using genomic in situ hybridization.

BACKGROUND: Interspecific hybridization is an effective strategy for germplasm innovation in sugarcane. Nobilization refers to the breeding theory of development and utilization of wild germplasm. Saccharum spontaneum is the main donor of resistance and adaptive genes in the nobilization breeding process. Chromosome transfer in sugarcane is complicated; thus, research of different inheritance patterns can provide guidance for optimal sugarcane breeding. RESULTS: Through chromosome counting and genomic in situ hybridization, we found that six clones with 80 chromosomes were typical S. officinarum and four other clones with more than 80 chromosomes were interspecific hybrids between S. officinarum and S. spontaneum. These data support the classical view that S. officinarum is characterized by 2n = 80. In addition, genomic in situ hybridization showed that five F1 clones were products of a 2n + n transmission and one F1 clone was the product of an n + n transmission in clear pedigree noble hybrids between S. officinarum and S. spontaneum. Interestingly, Yacheng 75-408 and Yacheng 75-409 were the sibling lines of the F1 progeny from the same parents but with different genetic transmissions. CONCLUSIONS: This is the first clear evidence of Loethers, Crystallina, Luohanzhe, Vietnam Niuzhe, and Nanjian Guozhe were typical S. officinarum by GISH. Furthermore, for the first time, we identified the chromosome transmission of six F1 hybrids between S. officinarum and S. spontaneum. These findings may provide a theoretical basis for germplasm innovation in sugarcane breeding and guidance for further sugarcane nobilization.

A new method based on SNP of nrDNA-ITS to identify Saccharum spontaneum and its progeny in the genus Saccharum.

The identification of germplasm resources is an important aspect of sugarcane breeding. The aim of this study was to introduce a new method for identifying Saccharum spontaneum and its progeny. First, we cloned and sequenced nuclear ribosomal DNA internal transcribed spacer (nrDNA-ITS) sequences from 20 Saccharum germplasms. Analysis of these nrDNA-ITS sequences showed a stable mutation at base 89. Primers (FO13, RO13, FI16, and RI16) were then designed for tetra-primer amplification refractory mutation system (ARMS) PCR based on mutations at base 89 of the nrDNA-ITS sequence. An additional 71 Saccharum germplasms were identified using this tetra-primer ARMS PCR method, which confirmed that the method using the described primers successfully identified Saccharum spontaneum and progeny. These results may help improve the efficiency of modern molecular breeding of sugarcane and lay a foundation for identification of sugarcane germplasms and the relationships among them.