Search Results (11)

Cycads, renowned as “living fossils”, are among the most ancient extant seed plants, playing a crucial role in understanding plant evolution and sex differentiation. Despite their importance, research on their genetics and sex differentiation remains scarce. This study investigates three species, represented by six samples, collected from various regions in Fujian Province, China, using whole-genome resequencing on the Illumina platform. The sequence data underwent rigorous quality control, alignment, and variant detection, focusing on SNP and InDel distribution and annotation. Among the studied species, Cycas revoluta exhibited the highest number of SNPs and the greatest heterozygosity values. Based on SNP data, phylogenetic trees and principal component analysis revealed distinct clusters, with the three C. revoluta samples forming one cluster, while the two C. szechuanensis samples and the C. taiwaniana sample were grouped separately. Gene function using COG and GO annotations, and KEGG enrichment analysis, all highlighted differences in genomic structure and functional gene distribution between male and female cycads. Notably, genes associated with sex differentiation, such as MADS-box and auxin-responsive protein genes, were shown, while other transcription factors showed distinct annotations and enrichment patterns based on sex. This study improves our understanding of genetic variation, evolutionary relationships, and gene enrichment in cycads, providing a foundation for conservation, cultivation, and insights into sex differentiation mechanisms in these ancient plants. Full article

Background/Objectives: Targeted delivery of antigens to dendritic cells (DCs) is an effective strategy for enhancing vaccine efficacy. Methods: In this study, dual-targeting fusion proteins (GRFT-VHH54 and GRFT-VHH74) were constructed by fusing Griffithsin (GRFT), an algae-derived lectin with enveloped virus-binding properties, to DC-specific binding nanobodies (VHH54 and VHH74). Vaccines were formulated by combining the inactivated H9N2 avian influenza virus with these fusion proteins, and the potential of the fusion proteins to enhance vaccine-induced immunity in chickens was systematically evaluated. For parallel comparison, control groups included H9N2 avian influenza vaccines containing the inactivated virus alone, the inactivated virus with the immune enhancer CVCVA5, and a commercial H9N2 avian influenza inactivated vaccine. Results: At 4 weeks post-immunization, chickens vaccinated with the inactivated H9N2 virus combined with the GRFT-VHH74 fusion protein (1/2 H9+GRFT-VHH74) exhibited significantly enhanced humoral, mucosal, and cellular immune responses compared to those vaccinated with the inactivated H9N2 virus alone or the commercial H9N2 vaccine (p < 0.05). Additionally, chickens in the 1/2 H9+GRFT-VHH74 group exhibited enhanced resistance to the heterologous H9N2 subtype avian influenza virus, achieving a 90% protection rate, which was higher than that of the other groups. Conclusions: These results indicate that the GRFT-VHH74 fusion protein has significant potential for advancing the development of inactivated vaccines against the H9N2 subtype avian influenza. Furthermore, it provides valuable insights for enhancing the immunogenicity and efficacy of inactivated vaccines targeting other avian influenza subtypes. Full article

Leaf rolling is regarded as an important morphological trait in wheat breeding. Moderate leaf rolling is helpful to keep leaves upright and improve the photosynthesis of plants, leading to increased yield. However, studies on the identification of genomic regions/genes associated with rolling leaf have been reported less frequently in wheat. In this study, a rolling leaf mutant, T73, which has paired spikelets, dwarfism, and delayed heading traits, was obtained from a common wheat landrace through ethyl methanesulfonate mutagenesis. The rlT73 mutation caused an increase in the number of epidermal cells on the abaxial side and the shrinkage of bulliform cells on the adaxial side, leading to an adaxially rolling leaf phenotype. Genetic analysis showed that the rolling leaf phenotype was controlled by a single recessive gene. Further Wheat55K single nucleotide polymorphism array-based bulked segregant analysis and molecular marker mapping delimited rlT73 to a physical interval of 300.29–318.33 Mb on the chromosome arm 1BL in the Chinese Spring genome. We show that a point mutation at the miRNA165/166 binding site of the HD zipper class III transcription factor on 1BL altered its transcriptional level, which may be responsible for the rolling leaf phenotype. Our results suggest the important role of rlT73 in regulating wheat leaf development and the potential of miRNA-based gene regulation for crop trait improvement. Full article

Food allergy (FA) has become a global food safety issue. Evidence suggests that inflammatory bowel disease (IBD) can increase the incidence of FA, but it is mostly based on epidemiological studies. An animal model is pivotal for unraveling the mechanisms involved. However, dextran sulfate sodium (DSS)-induced IBD models may cause substantial animal losses. To better investigate the effect of IBD on FA, this study aimed to establish a murine model to fit both IBD and FA symptoms. Firstly, we compared three DSS-induced colitis models by monitoring survival rate, disease activity index, colon length, and spleen index, and then eliminated the colitis model with a 7-day administration of 4% due to high mortality. Moreover, we evaluated the modeling effects on FA and intestinal histopathology of the two models selected and found the modeling effects were similar in both the colitis model with a 7-day administration of 3% DSS and the colitis model with long-term administration of DSS. However, for animal survival reasons, we recommend the colitis model with long-term administration of DSS. Full article

Wheat powdery mildew (Blumeria graminis f. sp. tritici, Bgt, recently clarified as B. graminis s. str.), is one of the most destructive diseases of wheat. Pm60 is a nucleotide-binding leucine-rich repeat (NLR) gene that confers race-specific resistance to Bgt. Allelic variants (Pm60, Pm60a, and Pm60b) were found in Triticum urartu and T. dicoccoides, the wild progenitors of wheat. In the present study, we studied the diversity of the Pm60 locus in a large set of wheat germplasm and found 20 tetraploid wheats harboring the Pm60 alleles, which correspond to three novel haplotypes (HapI–HapIII). HapI (Pm60 allele) and HapII (Pm60a allele) were present in domesticated tetraploid wheats, whereas HapIII (Pm60a allele) was identified in wild tetraploid T. araraticum. A sequence comparison of HapII and HapIII revealed that they differed by three SNPs and a GCC deletion. Results of the phylogenetic analysis revealed that HapII was more closely related to the functional haplotype MlIW172. Infection tests showed that HapII-carrying lines display a partial resistance response to Bgt#GH, while HapI was susceptible. Our results provide insights into the genetic evolution of the Pm60 locus and potential valuable alleles for powdery mildew resistance breeding. Full article

The NAC transcription factor (TF) family is one of the largest TF families in plants, which has been widely reported in rice, maize and common wheat. However, the significance of the NAC TF family in wild emmer wheat (Triticum turgidum ssp. dicoccoides) is not yet well understood. In this study, a genome-wide investigation of NAC genes was conducted in the wild emmer genome and 249 NAC family members (TdNACs) were identified. The results showed that all of these genes contained NAM/NAC-conserved domains and most of them were predicted to be located on the nucleus. Phylogenetic analysis showed that these 249 TdNACs can be classified into seven clades, which are likely to be involved in the regulation of grain protein content, starch synthesis and response to biotic and abiotic stresses. Expression pattern analysis revealed that TdNACs were highly expressed in different wheat tissues such as grain, root, leaves and shoots. We found that TdNAC8470 was phylogenetically close to NAC genes that regulate either grain protein or starch accumulation. Overexpression of TdNAC8470 in rice showed increased grain starch concentration but decreased grain Fe, Zn and Mn contents compared with wild-type plants. Protein interaction analysis indicated that TdNAC8470 might interact with granule-bound starch synthase 1 (TdGBSS1) to regulate grain starch accumulation. Our work provides a comprehensive understanding of the NAC TFs family in wild emmer wheat and establishes the way for future functional analysis and genetic improvement of increasing grain starch content in wheat. Full article

The zinc/iron-regulated transporter-like protein (ZIP) family has a crucial role in Zn homeostasis of plants. Although the ZIP genes have been systematically studied in many plant species, the significance of this family in wild emmer wheat (Triticum turgidum ssp. dicoccoides) is not yet well understood. In this study, a genome-wide investigation of ZIPs genes based on the wild emmer reference genome was conducted, and 33 TdZIP genes were identified. Protein structure analysis revealed that TdZIP proteins had 1 to 13 transmembrane (TM) domains and most of them were predicted to be located on the plasma membrane. These TdZIPs can be classified into three clades in a phylogenetic tree. They were annotated as being involved in inorganic ion transport and metabolism. Cis-acting analysis showed that several elements were involved in hormone, stresses, grain-filling, and plant development. Expression pattern analysis indicated that TdZIP genes were highly expressed in different tissues. TdZIP genes showed different expression patterns in response to Zn deficiency and that 11 genes were significantly induced in either roots or both roots and shoots of Zn-deficient plants. Yeast complementation analysis showed that TdZIP1A-3, TdZIP6B-1, TdZIP6B-2, TdZIP7A-3, and TdZIP7B-2 have the capacity to transport Zn. Overexpression of TdZIP6B-1 in rice showed increased Zn concentration in roots compared with wild-type plants. The expression levels of TdZIP6B-1 in transgenic rice were upregulated in normal Zn concentration compared to that of no Zn. This work provides a comprehensive understanding of the ZIP gene family in wild emmer wheat and paves the way for future functional analysis and genetic improvement of Zn deficiency tolerance in wheat. Full article

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating fungal disease of wheat. The wild emmer gene, Yr15 (Wtk1), which confers a strong broad-spectrum resistance to Pst isolates, is composed of kinase and pseudokinase domains. The analysis of 361 wild emmer accessions from a wide range of natural habitats confirms that functional Wtk1 is distributed mainly along a narrow axis from Mt. Carmel to Mt. Hermon regions, in the northern part of Israel, where environmental conditions are favorable to the onset of stripe rust. An analysis of full-length Wtk1 DNA sequences from 49 wild emmer accessions identified three haplotypes and extremely low nucleotide diversity (π = 0.00002). The sequence diversity of Wtk1 is 9.5 times lower than that of broad-spectrum partial resistance gene Yr36 (π = 0.00019), and both are in sharp contrast to the high level of nucleotide diversity previously reported for race-specific resistance genes (e.g., Lr10 and Pm3). However, the nonfunctional wtk1 sequences possess high level of nucleotide diversity (π = 0.07). These results may reflect the different resistance mechanisms and the different evolutionary processes that shaped these resistance genes. Yr15 was absent in 189 Chinese wheat landraces and was present in only 1.02% of the 583 tested modern Chinese wheat cultivars. These results corroborate our previous results showing that Yr15 was absent in 94% of a worldwide collection of 513 wheat cultivars, therefore indicating the importance of Yr15 in wheat stripe rust resistance breeding programs in China and elsewhere around the globe. Full article

Wild emmer wheat (Triticum dicoccoides), the tetraploid progenitor of cultivated wheats, is indigenous to the Near East Fertile Crescent. An important center of distribution is found today in and around the catchment area of the upper Jordan Valley in Israel and surrounding regions. In the current study, the field stripe rust resistance and morphological traits were analyzed using 98 sample accessions that represented the geographical distribution of wild emmer populations in Israel and its vicinity. The resistance tests at two field locations revealed that the majority of the wild emmer accessions possess quantitative resistance against stripe rust. This could be due to the high frequency of Yr36 in the wild emmer populations. The identification of potentially novel stripe rust resistance in this set of germplasm is highly significant. In total, 11 morphological traits were examined in this study. Wide range of natural variation was revealed in the tested morphological traits. Most of the morphological traits had significant correlations with climate variables, indicating that the local environmental conditions have a profound effect on shaping the genetic structure of wild emmer wheat. Our results suggest that wild emmer wheat has the enormous potential to improve stripe rust resistance and various important agronomical traits in wheat. Full article

Glu-1Ay, one of six genes encoding a high molecular weight glutenin subunit (HMW-GS), is frequently silenced in hexaploid common wheat. Here, an active allele of Glu-1Ay was integrated from wild emmer wheat (Triticum turgidum ssp. dicoccoides) accession D97 into the common wheat (Triticum aestivum) cultivar Chuannong 16 via the repeated self-fertilization of the pentaploid interspecific hybrid, culminating in the selection of a line TaAy7-40 shown to express the wild emmer Glu-1Ay allele. The open reading frame of this allele was a 1830 bp long sequence, demonstrated by its heterologous expression in Escherichia coli to encode a 608-residue polypeptide. Its nucleotide sequence was 99.2% identical to that of the sequence within the wild emmer parent. The TaAy7-40 introgression line containing the active Glu-1Ay allele showed higher protein content, higher sodium dodecyl sulfate (SDS) sedimentation value, higher content of wet gluten in the flour, higher grain weight, and bigger grain size than Chuannong 16. The end-use quality parameters of the TaAy7-40 were superior to those of the medium gluten common wheat cultivars Mianmai 37 and Neimai 9. Thus, the active Glu-1Ay allele might be of potential value in breeding programs designed to improve wheat flour quality. Full article

The Beibu Gulf (also named the Gulf of Tonkin), located in the northwest of the South China Sea, is representative of a bay suffering from turbulence and contamination associated with rapid industrialization and urbanization. In this study, we aim to provide the novel baseline levels of heavy metals for the research area. Concentrations of five heavy metals (i.e., Cu, Pb, Zn, Cd and Cr) were determined in surface sediments from 35 sites in the eastern Beibu Gulf. The heavy metal content varied from 6.72 to 25.95 mg/kg for Cu, 16.99 to 57.98 mg/kg for Pb, 73.15 to 112.25 mg/kg for Zn, 0.03 to 0.12 mg/kg for Cd, and 20.69 to 56.47 mg/kg for Cr, respectively. With respect to the Chinese sediment quality criteria, sediments in the eastern Beibu Gulf have not been significantly affected by coastal metal pollutions. The results deduced from the geoaccumulation index (I_geo) showed that the study area has been slightly polluted by Pb, which might be caused by non-point sources. Relatively high concentrations of Cu, Pb and Cd were found around the coastal areas of Guangxi province, the Leizhou Peninsula and the northwest coast of Hainan Island, whereas the highest concentrations of Zn and Cr were found on the northwest coast of Hainan Island. Spatial distribution patterns of the heavy metals showed that bioavailable fractions of Pb were higher than in the residual fractions, while Cu and Cd concentrations in exchangeable and carbonate fractions were relatively higher than those in the bioavailable fractions. Hierarchical clustering analysis suggested that the sampling stations could be separated into three groups with different geographical distributions. Accompanying their similar spatial distribution in the study area, significant correlation coefficients among Cu, Cd and Pb were also found, indicating that these three metals might have had similar sources. Overall, the results indicated that the distribution of these heavy metals in the surface sediments collected from the Beibu Gulf was complex. Full article