Geese, descendants of migratory birds, have preserved the distinct reproductive and lipid metabolism traits of their wild ancestors.  Therefore, compared to other poultry, geese have lower egg production ability and greater susceptibility to fatty liver.  Recent research underscores the impact of lipid metabolism disorders on female reproductive health.  In this context, we observed reproductive disorders (RD) and lipid metabolism anomalies in certain geese populations.  This study systematically elucidated the differences between RD and normal geese at various levels, including genomics, transcriptomics, bile acid metabolomics, and microbiomics, revealing the crucial role of microorganisms.  Our study provides a thorough examination of the ovarian anatomical, histological, and transcriptomic profiles between normal and RD geese.  Genomic analyses pinpoint mutations in genes associated with bile acid metabolism, highlighting their potential role in RD pathogenesis.  The genomic discoveries are substantiated by precise bile acid assays and ileum transcriptome analyses, which expose a significant disruption in bile acid absorption, activation of FXR, and an increase in serum chenodeoxycholic acid (CDCA) concentrations within RD geese.  Notably, 16S rRNA sequencing uncovers significantly greater beta diversity in the ileum microbiota of RD geese than in the normal group.  Both Wilcoxon rank sum test and LEfSe analyses highlighted a marked increase in Romboutsia abundance in RD geese.  Experimental cultivation of microbiota with CDCA supplementation confirms the impact of CDCA on Romboutsia lituseburensis proliferation.  Gavage experiments with R. lituseburensis elucidate its involvement in primary follicle reduction via immune-mediated pathways.  Collectively, our multifaceted analysis unravels the intricate involvement of Romboutsia in goose RD, offering insights from genetic, physiological, and microbial dimensions.  Our findings not only deepen understanding of the etiology of RD in geese but also suggest potential avenues for therapeutic interventions targeting bile acid metabolism and modulation of specific microbiota components.

 

Cadmium (Cd) contamination in wheat farmland is increasing at an alarming rate, posing threats to food security and public health.  Breeding and utilizing wheat varieties characterized by low Cd accumulation levels constitute an effective strategy in the battle against wheat Cd contamination.  The adoption of molecular marker-assisted approaches can greatly expedite the selection and enhancement of wheat varieties with low Cd accumulation.  Nonetheless, research concerning the genes associated with wheat cadmium accumulation remains scarce.  In this study, a high-density 660K SNP array was employed for conducting a genome-wide association study (GWAS) on the grain Cd concentration (GCdC), bioconcentration factor (BCF) and translocation factor (TF) in 175 wheat germplasms.  The findings revealed 401 significant SNPs identified across three diverse environments.  Linkage disequilibrium analysis revealed 30 core quantitative trait loci (QTLs) capable of reliably modulating wheat Cd accumulation phenotypes.  Through gene annotation, transcriptomics, and gene molecular features, four candidate genes (TraesCS7B02G000200, TraesCS4A02G035900, TraesCS4A02G040900, and TraesCS5D02G564000) were identified as potential constituents in the biological process of wheat Cd accumulation.  Furthermore, six wheat germplasms exhibiting low grain Cd accumulation were isolated, and two kompetitive allele specific PCR (KASP) markers conducive to breeding selection were developed.  These findings provide valuable genetic resources for cultivating wheat with low Cd accumulation and establish a foundation for understanding the molecular mechanisms underlying low Cd accumulation in wheat.  The candidate genes and KASP markers elucidated in this research have potential for effective use in genetic enhancement and marker-assisted selection in the breeding of wheat with low Cd accumulation.

Pyrus pyrifolia Nakai ‘Whangkeumbae’ is a sand pear fruit with excellent nutritional quality and taste.  However, the industrial development of pear fruit is significantly limited by its short shelf life.  Salicylic acid (SA), a well-known phytohormone, can delay fruit senescence and improve shelf life.  However, the mechanism by which SA regulates CONSTANS-LIKE genes (COLs) during fruit senescence and the role of COL genes in mediating fruit senescence in sand pear are poorly understood.  In this study, 22 COL genes were identified in sand pear, including four COLs (PpCOL8, PpCOL9a, PpCOL9b, and PpCOL14) identified via transcriptome analysis and 18 COLs through genome-wide analysis.  These COL genes were divided into three subgroups according to the structural domains of the COL protein.  PpCOL8, with two B-box motifs and one CCT domain, belonged to the first subgroup.  In contrast, the other three PpCOLs, PpCOL9a, PpCOL9b, and PpCOL14, with similar conserved protein domains and gene structures, were assigned to the third subgroup.  The four COLs showed different expression patterns in pear tissues and were preferentially expressed at the early stage of fruit development.  Moreover, the expression of PpCOL8 was inhibited by exogenous SA treatment, while SA up-regulated the expression of PpCOL9a and PpCOL9b.  Interestingly, PpCOL8 interacts with PpMADS, a MADS-box protein preferentially expressed in fruit, and SA up-regulated its expression.  While the production of ethylene and the content of malondialdehyde (MDA) were increased in PpCOL8-overexpression sand pear fruit, the antioxidant enzyme (POD and SOD) activity and the expression of PpPOD1 and PpSOD1 in the sand pear fruits were down-regulated, which showed that PpCOL8 promoted sand pear fruit senescence.  In contrast, the corresponding changes were the opposite in PpMADS-overexpression sand pear fruits, suggesting that PpMADS delayed sand pear fruit senescence.  The co-transformation of PpCOL8 and PpMADS also delayed sand pear fruit senescence.  The results of this study revealed that PpCOL8 can play a key role in pear fruit senescence by interacting with PpMADS through the SA signaling pathway.

Close planting of dwarf varieties is currently the main cultivation direction for pear trees, and the screening of excellent dwarf varieties is an important goal for breeders.  In this study, the dwarfing pear variety ‘601D’ and its vigorous mutant ‘601T’ were used to show their biological characteristics and further explore the dwarfing mechanism in ‘601D’.  The biological characteristics showed that ‘601D’ had a shorter internode length, a shorter and more compact tree body, thicker and broader leaves, lower stomata density, larger stomata size (dimension), and higher photosynthetic capacity.  The biological characteristics of ‘601T’ showed notable contrasts.  The results of endogenous hormone tests indicated that the contents of abscisic acid (ABA), ABA-glucosyl ester, and GA4 were higher in ‘601D’, but the trans-zeatin content was lower.  By transcriptomic analysis, significant differences were found in the biosynthetic and metabolic pathways of ABA.  Related transcription factors such as bHLH, WRKY, and homeobox also participated in the regulation of plant dwarfing.  We therefore examined three hormones with obvious differences with ‘601T’, and found that only ABA could induce ‘601T’ to return to a dwarfing plant phenotype.  Therefore, we conclude that the dwarfing of ‘601D’ is caused by an excessive accumulation of ABA.  This study provides a new theoretical basis for breeding dwarf varieties.

Elevated activities of cytosolic fructose-1,6-bisphosphatase (cyFBPase) and sedoheptulose-1,7-bisphosphatase (SBPase) are associated with higher yields in plants.  In this study, the expression levels of the cyFBPase and SBPase genes were increased by overexpressing rape (Brassica napus) cDNA in tobacco (Nicotiana tabacum) plants.  The transgenic plants co-expressing cyFBPase and SBPase (TpFS), or expressing single cyFBPase (TpF) or SBPase (TpS) had 1.77-, 1.55-, 1.23-fold cyFBPase and 1.45-, 1.12-, 1.36-fold SBPase activities as compared to the wild-type (WT), respectively.  Photosynthesis rates of TpF, TpS and TpFS increased 4, 20 and 25% compared with WT plants.  The SBPase and cyFBPase positively regulated each other and functioned synergistically in transgenic tobacco plants.  In addition, the sucrose contents of the three transgenic plants were higher than that of WT plants.  The starch accumulation of the TpFS and TpS plants was improved by 53 and 37%, but slightly decreased in TpF plants.  Moreover, the transgenic tobacco plants harbouring SBPase and/or cyFBPase genes showed improvements in their growth, biomass, dry weight, plant height, stem diameter, leaf size, flower number, and pod weight.  In conclusion, co-expression of SBPase and cyFBPase may pave a new way for improving crop yield in agricultural applications.

The cereal cyst nematodes (Heterodera avenae, Heterodera filipjevi, Heterodera latipons) are considered to be one of the most important plant parasitic nematodes attacking most cereals and can cause significant crop losses (Sikora 1988).  In China, H. filipjevi (Madzhidov 1981) Stelter, 1984, was first reported from Henan province (Peng et al. 2010) and a few years later in Anhui province and Xinjiang Uygur Autonomous Region (Peng et al. 2016, 2018) .  In December 2017, a survey for cereal cyst nematodes on winter wheat was conducted in Shandong Province, China.  A total of 79 samples that including roots and rhizosphere soil were collected.  Cysts and second-stage juveniles (J2s) were isolated from each soil sample using the sieving-decanting method.  Wheat roots were stained with acid fusion to observe the development of cereal cyst nematodes.  One sample collected from Yangzhuan Village in Huanggang Town, Shan County of Heze City (GPS 34°38´23.10´´N, 116°05´42.95´´E), Shandong Province, was found that the wheat roots were heavily parasitized by cyst nematodes, and most of the nematodes in roots had developed to fourth-stage (J4) in mid-December of 2017.  The morphological and molecular studies of cyst and J2s were carried out to confirm the identification of H. filipjevi in one winter wheat field soil and root sample from Shan County.  The cysts were lemon shaped with prominent vulval cone, brown to black in colour.  Cuticle with irregular zig-zag pattern.  Neck prominent, vulval cone bifenestrate with horseshoe-shaped fenestra, bullae and underbridge strongly developed.  The main morphometrics of cysts (n=8) were length (including neck) (688 to 948 μm, mean=794 μm, standard deviation=87 μm), width (465 to 620 μm, mean=529 μm, standard deviation=63 μm), neck length (71.5 to 126.3 μm, mean=86.5 μm, standard deviation=9.2 μm), fenestra length (43.8 to 71.3 μm, mean=58.0 μm, standard deviation=15.1 μm), fenestra width (19.8 to 32.0 μm, mean=25.0 μm, standard deviation=3.9 μm), length of vulval slit (8.1 to 9.7 μm, mean=9.1 μm, standard deviation=0.5 μm) and length of underbridge (64.5 to 101.3 μm, mean=82.6 μm, standard deviation=12.8 μm).  Measurements of J2s (n=10); body length (556.7 to 617.0 μm, mean=584.3 μm, standard deviation=23.2 μm); stylet (22.8 to 24.1 μm, mean=23.3 μm, standard deviation=0.4 μm), tail (59.6 to 68.6 μm, mean=65.8 μm, standard deviation=3.5 μm) and hyaline tail terminus (35.9 to 41.1 μm, mean=38.6 μm, standard deviation=2.1 μm).  Genomic DNA was isolated from single cysts (n=6), and the internal transcribed spacer regions were amplified with primers TW81 (5´-GTTTCCGTAGGTGAACCTGC-3´) and AB28 (5´-ATATGCTTAAGTTCAGCGGGT-3´) (Joyce et al. 1994) and 28S rDNA-D2/D3 regions were amplified with primers D2A (5´-ACAAGTACCGTGAGGGAAAGTTG-3´) and D3B (5´-TCGGAAGGAACCAGCTACTA-3´) (Subbotin et al. 2006).  The obtained internal transcribed spacer regions (ITSs) sequences (GenBank accession MG859977) is 99% identical to those of H. filipjevi from Turkey (KR704292.1 and KR704304.1), the United States (KP878490.1 and GU079654.1) and China (KY448473.1 and KY448473.1).  The obtained 28S rDNA-D2/D3 sequences (GenBank accession MG859980) also to be 99 to 100% identical to those of H. filipjevi from China (GU083597.1, KT314235.1, GU083592.1).  The species-specific primers of H. filipjevi (HfF1, 5´-CAGGACGAAACTCATTCAACCAA-3´; HfR1, 5´-AGGGCGAACAGGAGAAGATTAGA-3´) were also used to identify this population (Peng et al. 2013), the specific band was obtained species-specific primers of H. filipjevi.  Based on the morphological and molecular data, the species of the cyst-forming nematode was identified as H. filipjevi.  As far as we know, this is the first report of H. filipjevi in Shandong Province, China.  The population density of H. filipjevi were found much higher than those of other CCN, it can serious infect winter wheat at seedling stage which often cause economically damaging to wheat, so the spread of H. filipjevi would be a risk for the cereal production of Shandong province. 

Brucella spp., an intracellular bacterium, uses its type IV secretion system (T4SS) to regulate host signaling pathways and promote intracellular survival, but the molecular mechanism of this process remains largely unknown. Here we found that increasing the abundance of acetylated protein in host cells promotes the intracellular survival of Brucella. Moreover, our results demonstrated that the Brucella effector protein BspF can impact protein acetylation modification in host cells by interacting with other intracellular proteases. We conducted LC-MS/MS to characterize the protein acetylation mediated by BspF. We identified that SNAP29 K103 was acetylated, and that acetylated SNAP29 inhibited its interaction with STX17, thereby regulating the autophagy and providing an environment for the intracellular survival of Brucella. Furthermore, our results provide the first report of a bacterial effector using acetylation to affect the SNAP29-STX17-VAMP8 complex, and inhibit the host's defense system. Our results suggest a vital role of SNAP29 acetylation in autophagy of host cells under intracellular infection, by specifically regulating the assemble of SNARE.