Distinct lung microbial community states in patients with pulmonary tuberculosis

An improved understanding of the lung microbiome may lead to better strategies to diagnose, treat, and prevent pulmonary tuberculosis(PTB). However, the characteristics of the lung microbiomes of patients with TB remain largely undefined. In this study, 163 bronchoalveolar lavage(BAL) samples were collected from 163 sputum-negative suspected PTB patients. Furthermore, 12 paired BAL samples were obtained from 12 Mycobacterium tuberculosis-positive(MTB+) patients before and after negative conversion following a two-month anti-TB treatment. The V3–V4 region of the 16 S ribosomal RNA(rRNA) gene was used to characterize the microbial composition of the lungs. The results showed that the prevalence of MTB in the BAL samples was 42.9%(70/163) among the sputum-negative patients. The α-diversity of lung microbiota was significantly less diverse in MTB+ patients compared with Mycobacterium tuberculosis-negative(MTB–) patients. There was a significant difference in β-diversity between MTB+ and MTB– patients. MTB+ patients were enriched with Anoxybacillus, while MTB– patients were enriched with Prevotella, Alloprevotella, Veillonella, and Gemella. There was no significant difference between the Anoxybacillus detection rates of MTB+ and MTB– patients. The paired comparison between the BAL samples from MTB+ patients and their negative conversion showed that BAL negative-conversion microbiota had a higher α-diversity. In conclusion, distinct features of airway microbiota could be identified between samples from patients with and without MTB. Our results imply links between lung microbiota and different clinical groups of active PTB.     

Noninvasive ultrasound deep brain stimulation of nucleus accumbens induces behavioral avoidance

Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens(NAc) in freely moving mice. Our results show that an acute ultrasound stimulation on the NAc, rather than the visual cortex or auditory cortex, led to a pronounced avoidance behavior, while repeated NAc ultrasound stimulation resulted in an obvious conditioned place aversion with changes in synaptic protein(Glu A1/2 subunit) expression. Notably, NAc ultrasound stimulation suppressed the morphine-induced conditioned place preference. The results provide evidence that NAc ultrasound stimulation can be applied as a potential noninvasive therapeutic option in treating psychiatric disorders.     

中华蜜蜂PLA2基因的生物信息学分析及响应高温胁迫的表达模式

磷脂酶A2 (PLA2)对细胞膜流动性、膜蛋白活性等细胞生理功能有重要调节作用。高温等环境压力对细胞的生理代谢有较大的影响,其在生物体抗逆过程中的调控作用一直备受关注。本研究以中华蜜蜂Hymenoptera: Apidae: Apis cerana cerana PLA2基因序列为基础,对其蛋白结构进行预测,分析该基因在不同温度和高温不同胁迫时间下的表达差异,以揭示该基因在中华蜜蜂抗高温过程中的生理功能。结果显示,中华蜜蜂PLA2基因包含745 bp的开放阅读框,编码169个氨基酸,蛋白分子量为19.3 kDa,无跨膜结构,不属于膜蛋白。氨基酸同源序列比对结果显示,中华蜜蜂PLA2序列与蜜蜂科昆虫的相似性最高,与其他膜翅目昆虫的相似性存在差异。qRT-PCR结果显示,PLA2在35℃、40℃和45℃处理下的表达量较高,较高的温度能诱导该基因表达的增加。同时,PLA2的表达受高温胁迫时间的影响,较长时间的高温胁迫导致PLA2基因的表达增加。本研究结果表明PLA2在中华蜜蜂应对高温胁迫时发挥重要生理功能。     

细胞色素P450 3A7羟化维生素D3的功能研究

本研究通过体外生化实验研究细胞色素P450 3A7对维生素D3的羟化作用。根据GenBank报道的序列设计特异引物,扩增cyp3a7的编码区,将cyp3a7的编码区插入到pcDNATM3.1/myc-His(-) A的XhoⅠ/Bam HⅠ,通过测序检测序列的正确性。pcDNA-CYP3A7及pcDNA分别瞬时转染293T细胞,48 h后收集细胞,提取S9组分,用Bradford法测定蛋白质浓度。S9组分经12%SDS-PAGE凝胶电泳和Western blotting检测,用myc抗体作为一抗检测CYP3A7在293T细胞的表达水平。0.6 mg S9组分与1μmol/L维生素D3于37℃孵育30 min,用4倍体积的氯仿甲醇(体积比为3∶1)抽提,有机相在氮气流下吹干,残基用于HPLC分析。结果显示,重组表达CYP3A7的293T细胞的S9组分通过Western blotting检测到了特异的约60 kD的条带,对照样品未检测到特异条带的蛋白质。重组表达CYP3A7的293T细胞S9组分的孵育样品通过HPLC检测到了25-羟基维生素D3,对照样品未检测到25-羟基维生素D3。结果表明重组表达的CYP3A7羟化维生素D3生成25-羟基维生素D3。本研究为进一步探究还有哪些P450参与维生素D3在鸡体内的代谢,为阐明其代谢途径提供理论依据。     

Polymorphism analysis and supertype definition of swine leukocyte antigen class I molecules in three-way crossbred (Landrace,Duroc, and Yorkshire) pigs: implications for the vaccine development of African swine fever virus

正Dear Editor,Swine major histocompatibility complex (MHC) is a highly polymorphic gene in pigs and is also called swine leukocyte antigen (SLA)(Fan et al., 2018). SLA is divided into three major categories, SLA Ⅰ (SLA-1,-2,-3), SLA Ⅱ, and SLA Ⅲ(Smith et al., 2005). SLA Ⅰ plays an important role in cellular immunity which can eliminate viruses and other foreign     

Depth‐dependent soil organic carbon dynamics of croplands across the Chengdu Plain of China from the 1980s to the 2010s

Agricultural soils have tremendous potential to sequester soil organic carbon (SOC) and mitigate global climate change. However, agricultural land use has a profound impact on SOC dynamics, and few studies have explored how agricultural land use combined with soil conditions affect SOC changes throughout the soil profile. Based on a paired soil resampling campaign in the 1980s and 2010s, this study investigated the SOC changes of the soil profile caused by agricultural land use and the correlations with parent material and topography across the Chengdu Plain of China. The results showed that the SOC content increased by 3.78 g C/kg in the topsoil (0–20 cm), but decreased in the 20–40 cm and 40–60 cm soil layers by 0.90 and 1.26 g C/kg respectively. SOC increases in topsoil were observed for all types of agricultural land. Afforestation on former agricultural land also caused SOC decreases in the 20–60 cm soil layers, while SOC decreases only occurred in the 40–60 cm soil layer for agricultural land using a traditional crop rotation (i.e. traditional rice–wheat/rapeseed rotation) and with rice–vegetable rotations converted from the traditional rotations. For each agricultural land use, SOC decreases in deep soils only occurred in high relief areas and in soils formed from Q4 (Quaternary Holocene) grey‐brown alluvium and Q4 grey alluvium that had a relatively low soil bulk density and clay content. The results indicated that SOC change caused by agricultural land use was depth dependent and that the effects of agricultural land use on soil profile SOC dynamics varied with soil characteristics and topography. Subsoil SOC decreases were more likely to occur in high relief areas and in soils with low soil bulk density and low clay content.     

A Cu-only superoxide dismutase from stripe rust fungi functions as a virulence factor deployed for counter defense against host-derived oxidative stress

Plants quickly accumulate reactive oxygen species (ROS) to resist against pathogen invasion, while pathogens strive to escape host immune surveillance by degrading ROS. However, the nature of the strategies that fungal pathogens adopt to counteract host-derived oxidative stress is manifold and requires deep investigation. In this study, a superoxide dismutase (SOD) from Puccinia striiformis f. sp. tritici (Pst) PsSOD2 with a signal peptide (SP) and the glycophosphatidyl inositol (GPI) anchor, strongly induced during infection, was analysed for its biological characteristics and potential role in wheat–Pst interactions. The results showed that PsSOD2 encodes a Cu-only SOD and responded to ROS treatment. Heterologous complementation assays in Saccharomyces cerevisiae suggest that the SP of PsSOD2 is functional for its secretion. Transient expression in Nicotiana benthamiana leaves revealed that PsSOD2 is localized to the plasma membrane. In addition, knockdown of PsSOD2 by host-induced gene silencing reduced Pst virulence and resulted in restricted hyphal development and increased ROS accumulation. In contrast, heterologous transient assays of PsSOD2 suppressed flg22-elicited ROS production. Taken together, our data indicate that PsSOD2, as a virulence factor, was induced and localized to the plasma membrane where it may function to scavenge host-derived ROS for promoting fungal infection.     

A Phytophthora capsici effector suppresses plant immunity via interaction with EDS1

EDS1 (Enhanced Disease Susceptibility 1) plays a crucial role in both effector-triggered immunity activation and plant basal defence. However, whether pathogen effectors can target EDS1 or an EDS1-related pathway to manipulate immunity is rarely reported. In this study, we identified a Phytophthora capsici Avirulence Homolog (Avh) RxLR (Arg-any amino acid-Leu-Arg) effector PcAvh103 that interacts with EDS1. We demonstrated that PcAvh103 can facilitate P. capsici infection and is required for pathogen virulence. Furthermore, genetic evidence showed that PcAvh103 contributes to virulence through targeting EDS1. Finally, PcAvh103 specifically interacts with the lipase domain of EDS1 and can promote the disassociation of EDS1–PAD4 (Phytoalexin Deficient 4) complex in planta. Together, our results revealed that the P. capsici RxLR effector PcAvh103 targets host EDS1 to suppress plant immunity, probably through disrupting the EDS1–PAD4 immune signalling pathway.     

OsmiR167a‐targeted auxin response factors modulate tiller angle via fine‐tuning auxin distribution in rice

Rice tiller angle determines plant growth density and further contributes grain production. Although a few genes have been characterized to regulate tiller angle in rice, the molecular mechanism underlying the control of tiller angle via microRNA is poorly understood. Here, we report that rice tiller angle is controlled by OsmiR167a‐targeted auxin response factors OsARF12, OsARF17 and OsARF25. In the overexpression of OsMIR167a plants, the expression of OsARF12, OsARF17 and OsARF25 was severely repressed and displayed larger tiller angle as well as the osarf12/osarf17 and osarf12/ osarf25 plants. In addition, those plants showed compromised abnormal auxin distribution and less sensitive to gravity. We also demonstrate that OsARF12, OsARF17 and OsARF25 function redundantly and might be involved in HSFA2D and LAZY1‐dependent asymmetric auxin distribution pathway to control rice tiller angle. Our results reveal that OsmiR167a represses its targets, OsARF12, OsARF17 and OsARF25, to control rice tiller angle by fine‐tuning auxin asymmetric distribution in shoots.