The Corylus mandshurica genome provides insights into the evolution of Betulaceae genomes and hazelnut breeding

Hazelnut is popular for its flavor,and it has also been suggested that hazelnut is beneficial to cardiovascular health because it is rich in oleic acid.Here,we report the first high-quality chromosome-scale genome for the hazelnut species Corylus mandshurica(2n=22),which has a high concentration of oleic acid in its nuts.The assembled genome is 367.67Mb in length,and the contig N50 is 14.85 Mb.All contigs were assembled into 11 chromosomes,and 28,409 protein-coding genes were annotated.We reconstructed the evolutionary trajectories of the genomes of Betulaceae species and revealed that the 11 chromosomes of the hazelnut genus were derived from the most ancestral karyotype in Betula pendula,which has 14 protochromosomes,by inferring homology among five Betulaceae genomes.We identified 96 candidate genes involved in oleic acid biosynthesis,and 10 showed rapid evolution or positive selection.These findings will help us to understand the mechanisms of lipid synthesis and storage in hazelnuts.Several gene families related to salicylic acid metabolism and stress responses experienced rapid expansion in this hazelnut species,which may have increased its stress tolerance.The reference genome presented here constitutes a valuable resource for molecular breeding and genetic improvement of the important agronomic properties of hazelnut.

一例BBS12基因复合杂合突变导致Bardet-Biedl综合征的诊断和基因检测分析

Bardet-Biedl综合征(Bardet-Biedl syndrome,BBS)是一种罕见的常染色体隐性遗传的纤毛相关疾病,其病因主要与编码BBS蛋白复合体BBSome、鞭毛内运输复合体等基因突变有关。本文报道了1例21岁的女性BBS患者,该患者具有肥胖、视网膜色素变性、双肾囊肿的典型特征,还存在2型糖尿病、非酒精性脂肪肝、亚临床甲状腺功能减退症、轻度传导性听力下降等不典型表现。全外显子组测序发现该患者的BBS12基因2号外显子存在复合杂合突变(c.188delC,p.T63fs和c.1993_1995del,p.665_665del)。进一步通过Sanger测序发现患者的父亲和母亲分别携带c.188delC(p.T63fs)和c.1993_1995del(p.665_665del)突变,但均无相关症状。综上所述,本病例报告发现了BBS12基因的两个新的突变位点(c.188delC,p.T63fs和c.1993_1995del,p.665_665del),为该疾病的研究提供了新的遗传资源,同时该病例还展示了患者从出生到成人期间的整个疾病发展过程,能够帮助临床医生更好地理解BBS。

Rho 1 participates in parasitoid wasp eggs maturation and host cellular immunity inhibition

Endoparasitoid wasps introduce venom into their host insects during the egglaying stage.Venom proteins play various roles in the host physiology,development,immunity,and behavior manipulation and regulation.In this study,we identified a venom protein,MmRhol,a small guanine nucleotide-binding protein derived from ovary in the endoparasitoid wasp Microplitis mediator and found that knockdown of its expression by RNA interference caused down-regulation of vitellogenin and juvenile hormone,egg production,and cocoons formation in the female wasps.We demonstrated that MmRho1 entered the cotton bollworm's(host)hemocytes and suppressed cellular immune responses after parasitism using immunofluorescence staining.Furthermore,wasp MmRhol interacted with the cotton bollworm's actin cytoskeleton rearrangement regulator diaphanous by yeast 2-hybrid and glutathione s-transferase pull-down.In conclusion,this study indicates that MmRho1 plays dual roles in wasp development and the suppression of the host insect cellular immune responses.

The effects of circadian rhythm on catechin accumulation in tea leaves

As the major bitter-and astringent-tasting components in tea leaves,catechins play an essential role in determining flavor characteristics and health benefits of tea products.This study analyzed the circadian rhythm effects on the accumulation pattern of catechins in tender leaves of three tea cultivars,'Huangkui'(HK),'Longjing43'(LJ43)and'Fuding Dabaicha'(FD).There were two major factors involved in the catechin regulation in tea plants:genetic background of the cultivar-specific regulation,and temporal effects of the circadian rhythm.Etiolated leaves of'HK'contained lower levels of catechins than'LJ43'and'FD'.The composition of EGCG in total catechins was significantly higher in'LJ43'leaves(65%)when compared with that in'HK'and'FD'(45%).The accumulation of individual catechins increased during the daytime but decreased overnight,especially over the time period of 22:00−02:00.The correlation analysis between catechins and environmental factors indicated catechin accumulation in tea leaves potentially resulted from a combined regulation of light and temperature.These findings provide new insights into our understanding of circadian rhythm regulation on flavor-important secondary metabolites in tea leaves.

Event-Related Potentials Analysis on Perception of Moving Object at Different Speeds

For this research,electroencephalography(EEG)was analyzed to investigate the perception ability of the brain for moving objects at different speeds.In this experiment,total six kinds of videos regarding license plates were created,moving at distinct speed of 0.26 m/s,0.36 m/s,0.46 m/s,0.56 m/s,0.66 m/s,and 0.76 m/s,respectively.In the semantic priming paradigm,the N400 effect was analyzed for each speed.The ERP results demonstrated that the N400 amplitude gradually reduced with increasing speed.At the three lower speeds,N400 was evoked evidently and mainly distributed in the centro-posterior region.At the three higher speeds,no significant N400 effect was found.The results concluded that the perception ability of the brain declined with the acceleration of the object’s moving speed and that the brain recognized the detailed information of the moving object when its speed was lower than 0.46 m/s.

Hybrid speciation via inheritance of alternate alleles of parental isolating genes

It is increasingly realized that homoploid hybrid speciation(HHS),which involves no change in chromosome number,is an important mechanism of speciation.HHS will likely increase in frequency as ecological and geographical barriers between species are continuing to be disrupted by human activities.HHS requires the establishment of reproductive isolation between a hybrid and its parents,but the underlying genes and genetic mechanisms remain largely unknown.In this study,we reveal by integrated approaches that reproductive isolation originates in one homoploid hybrid plant species through the inheritance of altemate alleles at genes that determine parental premating isolation.The parent species of this hybrid species are reproductively isolated by differences in flowering time and survivorship on soils containing high concentrations of iron.We found that the hybrid species inherits alleles of parental isolating major genes related to flowering time from one parent and alleles of major genes related to iron tolerance from the other parent.In this way,it became reproductively isolated from one parent by the difference in flowering time and from the other by habitat adaptation(iron tolerance).These findings and further modeling results suggest that HHS may occur relatively easily via the inheritance of alternate parental premating isolating genes and barriers.

Comparative analysis of peptidoglycan recognition proteins in endoparasitoid wasp Microplitis mediator

Peptidoglycan recognition proteins （PGRPs） are a family of innate immune receptors that specifically recognize peptidoglycans （PGNs） on the surface of a number of pathogens. Here, we have identified and characterized six PGRPs from endoparasitoid wasp, Microplitis mediator （MmePGRPs）. To understand the roles of PGRPs in parasitoid wasps, we analyzed their evolutionary relationship and orthology, expression profiles during different developmental stages, and transcriptional expression following infection with Gram-positive and -negative bacteria and a fungus. MmePGRP-S1 was significantly induced in response to pathogenic infection. This prompted us to evaluate the effects of RNA interference mediated gene specific knockdown ofMmePGRP-S1. The knockdown of MmePGRP-S1 （iMmePGRP-S1） dramatically affected wasps＇ survival following challenge by Micrococcus luteus, indicating the involvement of this particular PGRP in immune responses against Gram-positive bacteria. This action is likely to be mediated by the Toll pathway, but the mechanism remains to be determined. MmePGRP-S 1 does not play a significant role in anti-fungal immunity as indicated by the survival rate of iMmePGRP-S wasps. This study provides a comprehensive characterization of PGRPs in the economically important hymenopteran species M. mediator.

Oxidation resistance 1 （OXR1） participates in silkworm defense against bacterial infection through the JNK pathway

Bacterial infection causes enhanced reactive oxygen species （ROS） levels in insects. Oxidation resistance 1 （OXR1） plays an antioxidant role in eukaryotic organisms, including insects. In this report, we demonstrated that Pseudomonas aeruginosa and Staphylococcus aureus infection and hydrogen peroxide （H2O2） injection induced the expression of specific transcriptional isoforms of OXR1 in larval silkworms. We further showed that a Jun kinase （JNK） pathway inhibitor, SP600125, down-regulated expression of OXRI during infection, leading to elevated H2O2 levels in the hemolymph, resulting in lower viability of the injected bacteria inside the silkworm larvae. Our study suggests that OXR1 participates in protecting larval silkworms from oxidative stress and bacterial infection through the JNK pathway.

Statistical analysis of residential building energy consumption in Tianjin

To analyze the effect of energy conservation policies on energy consumption of residential buildings, the characteristics of energy consumption and indoor thermal comfort were investigated in detail in Tianjin, China, based on official statistical yearbook and field survey data. A comprehensive survey of 305 households indicates that the mean electricity consumption per household is 3215kWh/a, in which annual cooling electricity consumption is 344kWh/a, and the mean natural gas consumption for cooking is 103.2m3/a. Analysis of 3966 households data shows that space heating average intensity of residential buildings designed before 1996 is 133.7kWh/（m^2.a）, that of buildings designed between 1996 and 2004 is 117.2 kWh/（m^2.a）, and that of buildings designed after 2004 is 105.0kWh/（m^2.a）. Apparently, enhancing the performance of envelops is effective in reducing space heating intensity. Furthermore, the results of questionnaires show that 18% of the residents feel slightly warm and hot respectively, while 3% feel slightly cold in winter. Therefore, the electricity consumption in summer will rise for meeting indoor thermal comfort.