Improvement on molecular sex identification primers for Passeriform bird species

The primer pair sex1/sex2,which can be widely applied for sex identification in Galliform species,was used to determine the sex of 17 Passeriform species.As CHD-W fragments tended to be preferentially amplified,which may cause unnecessary misidentification in bird species with little difference between CHD-Z and CHD-W,we modified sex1 and sex2,obtaining sex1' and sex-mix respectively.Primer sets were then recombined to conduct sex identification.After testing several Passeriforme birds of known sex,we found that the primer pair sex1'/sex2 was better at limiting the preferential amplification of CHD-W fragments.As they are being frequently used in sex allocation study of Aegithalos concinnus and song learning research of Lonchura striata,we can expect more applications of this primer pair to further studies in Passeriformes.

Identification of clade-wide putative cis-regulatory elements from conserved non-coding sequences in Cucurbitaceae genomes

Cis-regulatory elements regulate gene expression and play an essential role in the development and physiology of organisms.Many conserved non-coding sequences(CNSs)function as cis-regulatory elements.They control the development of various lineages.How-ever,predicting clade-wide cis-regulatory elements across several closely related species remains challenging.Based on the relationship between CNSs and cis-regulatory elements,we present a computational approach that predicts the clade-wide putative cis-regulatory elements in 12 Cucurbitaceae genomes.Using 12-way whole-genome alignment,we first obtained 632112 CNSs in Cucurbitaceae.Next,we identified 16552 Cucurbitaceae-wide cis-regulatory elements based on collinearity among all 12 Cucurbitaceae plants.Furthermore,we predicted 3271 potential regulatory pairs in the cucumber genome,of which 98 were verified using integrative RNA sequencing and ChIP sequencing datasets from samples collected during various fruit development stages.The CNSs,Cucurbitaceae-wide cis-regulatory elements,and their target genes are accessible at http://cmb.bnu.edu.cn/cisRCNEs_cucurbit/.These elements are valuable resources for functionally annotating CNSs and their regulatory roles in Cucurbitaceae genomes.

The rhythmic expression of genes controlling flowering time in southern and northern populations of invasive Ambrosia artemisiifolia

Aims Flowering time has been suggested to be an important adaptive trait during the dispersal of invasive species,and identifying the molecu-lar mechanisms underlying flowering time may provide insight into the local adaptation during the process of invasion.Here,we con-ducted a preliminary exploration on the genetic basis of the differ-entiation of flowering time in Ambrosia artemisiifolia.Methods using relative real-time fluorescent quantitative polymerase chain reaction,we investigated the expression levels of eight flowering-related genes,including AP1,FT,SOC1,CRY2,FKF1,GI,CO2 and SPY,in leaves and flowers at different time points in individuals from northern beijing and southern Wuhan populations that exhibit significant differences in flowering times to identify any rhythmic changes in gene expression and their association with differential flowering times.Important Findings The differentiation of flowering time in the A.artemisiifolia popula-tions was closely associated with five genes involved in flowering pathways.The floral pathway integrators FT and SOC1 and floral meristem identity gene AP1 exhibited increased expression during flowering.The photoreceptor CRY2 in the light-dependent path-way and the SPY gene in the gibberellin pathway displayed specific expression patterns over time.in earlier-flowering beijing plants,CRY2 expression was lower and SPY expression was higher than in Wuhan plants.The expression patterns of these five genes sug-gest a molecular basis for the differentiation of flowering time in A.artemisiifolia.

YR36/WKS1-Mediated Phosphorylation of PsbO,an Extrinsic Member of Photosystem Ⅱ,Inhibits Photosynthesis and Confers Stripe Rust Resistance in Wheat

Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive high-temperature adult-plant resistance gene and confers resistance to a broad spectrum of Pst races.We previously showed that WKS1 phosphorylates the thylakoid ascorbate peroxidase protein and reduces its ability to detoxify peroxides,which may contribute to the accumulation of reactive oxygen species(ROS).WKS1-mediated Pst resistance is accompanied by leaf chlorosis in Pst-infected regions,but the un-derlying mechanisms remain elusive.Here,we show that WKS1 interacts with and phosphorylates PsbO,an extrinsic member of photosystem Ⅱ(PS Ⅱ),to reduce photosynthesis,regulate leaf chlorosis,and confer Pst resistance.A point mutation in PsbO-A1 or reduction in its transcript levels by RNA interference resulted in chlorosis and reduced Pst sporulation.Biochemical analyses revealed that WKS1 phosphorylates PsbO at two conserved amino acids involved in physical interactions with PS Ⅱ and reduces the binding affinity of PsbO with PS Ⅱ.Presumably,phosphorylated PsbO proteins dissociate from the PS Ⅱ complex and then un-dergo rapid degradation by cysteine and aspartic proteases.Taken together,these results demonstrate that perturbations of wheat PsbO by point mutation or phosphorylation by WKS1 reduce the rate of photo-synthesis and delay the growth of Pst pathogen before the induction of ROS.

Variation in morphological traits in a recent hybrid zone between closely related Quercus liaotungensis and Q.mongolica(Fagaceae)

Aims Hybridization usually leads to gene introgression between related spe-cies in hybrid zones,associated with complex patterns of morpho-logical variation.Nevertheless,previous studies have tended to ignore the effects of geographic variation in hybridization rates on species taxonomy.This study aims to investigate the variation of morphologi-cal traits between two sympatric and taxonomically confused oak spe-cies,Quercus liaotungensis and Q.mongolica,and reveal the effects of hybridization rates on morphological traits and the taxonomic boundary.Methods We used seven microsatellite loci to evaluate species status and measured 15 morphological traits in 26 trees in the recent hybrid zone between Q.liaotungensis and Q.mongolica,and we char-acterized the differences between the two oak species and their hybrids for the investigated traits.Important Findingsmolecular analyses indicated that 74%of 78 sampled maternal trees were hybrids between Q.liaotungensis and Q.mongolica although the observed morphological variation suggested that they had remained distinct species.across all of the differentiated leaf and reproductive traits,the hybrids expressed patterns similar to Q.liaotungensis,which may suggest dominant expression of paren-tal characters.These results are consistent with our expectation that hybrids will be difficult to distinguish from parental species in a recent hybrid zone.

Molecular demographic history of the Hainan Peacock Pheasant(Polyplectron katsumatae) and its conservation implications

Knowledge of the historical responses of animal species to climate changes is critical for understanding their evolutionary history and conservation.During the late Quaternary period,Southeast Asia had a larger land area than today due to lower sea levels,and its terrestrial landscape was covered by extensive forests and savannah.To date,however,the general fluctuations in landscape distribution and their impacts on the demographics history of native species during the late Quaternary periods are still disputed.Specifically,the responses of animals on Hainan Island,which is located in the northernmost region of Southeast Asia,to historical climate changes,are poorly understood.Here,we performed a series of demographic analyses based on mitochondrial DNA genes to examine the response of the resident Hainan Peacock Pheasant(Polyplectron katsumatae) to climate change.Unlike the pattern of population collapse during the ice age and expansion during the warming period,we detected a historical expansion pattern in the demographic history of Hainan Peacock Pheasant through the late Quaternary period.It was concluded that the Hainan Peacock Pheasant survived through the late Quaternary periods,despite of its currently limited distribution and population size on Hainan Island.Anthropogenic influences must be considered in conservation planning due to their impacts on currently fragmented habitats and populations.

The Genome of Medicinal Plant Macleaya cordata Provides New Insights into Benzylisoquinoline Alkaloids Metabolism

The overuse of antibiotics in animal agriculture and medicine has caused a series of potential threats to public health. Macleaya cordata is a medicinal plant species from the Papaveraceae family, providing a safe resource for the manufacture of antimicrobial feed additive for livestock. The active constituents from M. cordata are known to include benzylisoquinoline alkaloids （BIAs） such as sanguinarine （SAN） and chelerythrine （CHE）, but their metabolic pathways have yet to be studied in this non-model plant. The active biosynthesis of SAN and CHE in M. cordata was first examined and confirmed by feeding ^13C-labeled tyrosine. To gain further insights, we de novo sequenced the whole genome of M. cordata, the first to be sequenced from the Papaveraceae family. The M. cordata genome covering 378 Mb encodes 22,328 predicted protein-coding genes with 43.5% being transposable elements. As a member of basal eudicot, M. cordata genome lacks the paleohexaploidy event that occurred in almost all eudicots. From the genomics data, a complete set of 16 metabolic genes for SAN and CHE biosynthesis was retrieved, and 14 of their biochemical activities were validated. These genomics and metabolic data show the conserved BIA metabolic pathways in M. cordata and provide the knowledge foundation for future productions of SAN and CHE by crop improvement or microbial pathway reconstruction.

Real-time digital data of international passengers will shine in the precaution of epidemics

International movement plays an important role in spatial spread of infectious diseases.Here,we share two successful COVID-19 interventions based on real-time digital information collected from international passengers,which have been performed in Greece and China respectively.Both of the interventions demonstrated good performance and showed the potential of real-time digital data in containing the spread.However,several key points should not be ignored when we promote similar strategies.