Expression and functional analysis of the Follistatin-like 3 (FSTL3) gene in the sheep ovary during the oestrous cycle

Follistatin-like 3 (FSTL3) is a regulator of cellular apoptosis and was previously identified via RNA-Seq to be associated with follicular development in mammalian ovaries. However, the mechanism underlying the FSTL3 regulation of oestrus in sheep remained poorly understood. In this study, the oestrogen (E2) and progesterone (P4) concentrations in blood were detected, and the expression level and functional analysis of FSTL3 in the ovary were studied during the different reproductive stage in Aohan fine wool sheep (seasonal breeding breed in China). The concentrations of E2 and P4 at the anestrus were significantly lower compared to dioestrus, proestrus and oestrus stages. Higher expression levels of FSTL3 were observed in the sheep ovary, hypothalamus, and thyroid. During different reproductive stages, higher expression levels were found during the stages of dioestrus and proestrus, while lower levels were found during the oestrus and anestrus stages. Functional analysis of FSTL3 was performed in primary granulosa cells (GCs) of sheep. The concentration of E2 increased significantly after RNAi interference of FSTL3, while the P4 level decreased. FSTL3 can decrease P4 levels, which might be involved in mediating oestrous cycle in sheep.     

河西走廊荒漠绿洲过渡带沙丘不同生境沙拐枣种群扩张特征研究

本研究以河西走廊荒漠绿洲边缘关键天然固沙植物沙拐枣为研究对象,对流动沙丘、固定沙丘不同生境的沙拐枣种群扩张特征进行调查,旨在更全面地认识其种群扩张特征和对干旱高温环境的适应对策。结果表明：（1）沙丘不同生境,沙拐枣种群扩张方式存在显著差异：在流动沙丘,丘间低地和过渡带以有性繁殖为主,无性繁殖为辅;迎风坡和背风坡以无性繁殖为主;而随着流动沙丘固定,种群以有性繁殖为主,无性繁殖数量和所占比重显著下降,并导致种群数量下降。（2）不同生境中沙拐枣种群密度与年龄均呈显著负相关,种群以幼龄苗为主,种群最大年龄出现在丘间低地,为36龄。（3）流动沙丘不同生境根状茎主要为2年生,多年生根状茎长度较短;而固定沙丘不同生境根状茎年龄结构较为均衡。     

DTA-6对两种食用豆生理代谢及产量的影响

为探究2-N,N-二乙氨基乙基己酸酯（diethyl aminoethyl hexanoate,DTA-6）对食用豆叶片的生理代谢及产量的调控效应,选用芸豆（英国红）和小豆（龙垦2号）为试验材料,采用大田完全随机试验方法,于芸豆和小豆的初花期叶面喷施DTA-6,以喷施清水为对照（CK）,测定各生育时期叶片光合参数、碳代谢产物、干物质、产量及产量构成因素。结果表明：DTA-6提高了2种食用豆各生育期的SPAD值、盛花期和鼓粒期的净光合速率（P_n）、蒸腾速率（T_r）、气孔导度（G_s）和胞间CO₂浓度（C_i）,显著增加了叶片蔗糖和可溶性糖的含量,促进了叶片淀粉的积累;与CK相比,DTA-6提高了2种食用豆的地上部单株干物质积累量,并且显著提高了芸豆和小豆鼓粒期荚分配率;DTA-6可有效调控2种食用豆的单株荚数、单株粒数和百粒重,从而提高产量,DTA-6处理的芸豆和小豆产量分别较CK增加13.30%和12.91%,增产显著。     

拟南芥DUF647家族成员RUS4植物表达载体的构建及亚细胞定位

ROOT UV-B SENSITIVE4 (RUS4)是拟南芥DUF647蛋白家族的一个功能未知的成员。RUS1和RUS2曾经报道和根UV-B-感应途径相关联,并在拟南芥早期幼苗形态发生和发育中发挥重要作用。为了探究RUS4的分子功能,本研究对RUS4蛋白进行了亚细胞定位分析。首先,我们通过Gateway TOPO载体系统,构建了融合蛋白表达载体pMDC83-RUS4;然后,通过农杆菌介导的花苞转化法,获得了转化pMDC83-RUS4的转基因拟南芥株系;对转基因植物叶肉原生质体的荧光显微镜观察显示,RUS4-GFP信号与叶绿体的自发荧光共定位,说明RUS4蛋白定位叶绿体中。该结果为进一步研究RUS4的分子功能奠定了良好的基础。     

Verrucosamide,a Cytotoxic 1,4-Thiazepane-Containing Thiodepsipeptide from a Marine-Derived Actinomycete

A new cytotoxic thiodepsipeptide, verrucosamide (1), was isolated along with the known, related cyclic peptide thiocoraline, from the extract of a marine-derived actinomycete, a Verrucosispora sp., our strain CNX-026. The new peptide, which is composed of two rare seven-membered 1,4-thiazepane rings, was elucidated by a combination of spectral methods and the absolute configuration was determined by a single X-ray diffraction study. Verrucosamide (1) showed moderate cytotoxicity and selectivity in the NCI 60 cell line bioassay. The most susceptible cell lines were MDA-MB-468 breast carcinoma with an LD₅₀ of 1.26 µM, and COLO 205 colon adenocarcinoma with an LD₅₀ of 1.4 µM. Also isolated along with verrucosamide were three small 3-hydroxy(alkoxy)-quinaldic acid derivatives that appear to be products of the same biosynthetic pathway.     

Koi herpesvirus and carp edema virus threaten common carp aquaculture in Croatia

Common carp (Cyprinus carpio) is a very important fish species for warm-water aquaculture in Croatia. All Croatian carp farms are subjected to a surveillance programme for the presence of koi herpesvirus (KHV), causing a deadly disease called koi herpesvirus disease (KHVD). However, there is no surveillance for other viral pathogens of importance like carp edema virus (CEV), a causative agent of koi sleepy disease (KSD). During regular testing within the KHVD surveillance programme, we tested samples for CEV simultaneously. The screening indicated possible outbreaks of KHVD and KSD. During 2016, KHVD broke out in an isolated area and soon thereafter a KHV eradication programme was successfully performed. However, during 2018 and 2019, two additional mortality events occurred in lakes in the southern part of Croatia during the spring. Samples from both events tested positive for CEV. An epidemiological investigation confirmed the introduction of infected carps from an infected farm to one of the lakes. To prevent the spreading of CEV into open waters, it is of utmost importance to introduce CEV testing before fish movement or to perform regular testing of all carp farms in the country to determine CEV prevalence for the purpose of implementation of control measures.     

CRISPR/Cas9技术敲除酿酒酵母gpd2基因对产2,3-丁二醇的影响

旨在利用CRISPR/Cas9基因编辑技术敲除酿酒酵母甘油-3-磷酸脱氢酶基因(gpd2),探究其对2,3-丁二醇产量的影响。根据酿酒酵母(Saccharomyces cerevisiae)W5甘油-3-磷酸脱氢酶基因(gpd2)设计供体片段及gRNA片段,将gRNA片段与可表达Cas9蛋白的敲除载体相连,之后将重组质粒及供体DNA片段转化到S. cerevisiae W5细胞中,根据表型筛选及PCR验证获得gpd2基因缺失菌株。结果表明目的基因gpd2敲除成功,基因缺失菌株与原始菌株经发酵实验相比,甘油产量下降22.01%,乙醇产量提高24.65%,2,3-丁二醇产量下降10.60%。gpd2基因的敲除并没有提高2,3-丁二醇的产量,原因可能是逐渐积累的NADH会优先被细胞内大量的乙醇脱氢酶所氧化,作用于乙醇的产生,而不是优先作用于2,3-丁二醇的合成。本实验构建了适用于酿酒酵母的基因敲除系统,该系统对进一步探究酿酒酵母其他代谢产物与2,3-丁二醇合成之间的关系具有实际的借鉴意义。     

Cf-2/Rcr3pim番茄品系对南方根结线虫的抗性测定

Cf-2/Rcr3~(pim)基因型番茄不仅能够抵御番茄叶霉菌的侵染,而且对马铃薯金线虫的寄生也有一定的抑制效果。为挖掘根结线虫的新抗性资源,本研究采用室内人工接种法测定了Cf-0/Rcr3~(pim)、Cf-2/Rcr3-3和Cf-2/Rcr3~(pim)基因型番茄品系对南方根结线虫的抗感性。抗性评价结果显示,Cf-0/Rcr3~(pim)品系对南方根结线虫表现高感,Cf-2/Rcr3-3品系为中感,而Cf-2/Rcr3~(pim)品系则为感病。与Cf-0/Rcr3~(pim)和Cf-2/Rcr3-3基因型相比,Cf-2/Rcr3~(pim)基因型番茄品系虽然对南方根结线虫侵染的敏感性略低,但是不能阻止线虫在根系上的大量繁殖,不适于根结线虫的防控应用。     

川渝地区地方和育成大豆品种SSR标记多样性分析?

利用基本均匀分布于大豆20条染色体的135对SSR标记，对232份包括6个地方品种地域亚群和1个育成品种亚群进行全基因组扫描。结果表明：所有的标记都有多态性，所有检测到的位点都是纯合基因型，说明所选用品种高度纯合，每个标记存在2～4个等位变异，平均2.66个。亚群多态信息含量变异范围0.2751-0.3165，整个群体为0.3208；亚群内Nei遗传距离变异范围0.325 8～0.359 4，整个群体为0.3711，说明川渝地区大豆遗传变异较小。亚群间的遗传一致度（GI ≥ 0.8862）较高，亚群间遗传距离（GD ≤ 0.1208）较小，地方品种亚群间遗传差异更小，育成品种亚群与自然地域亚群的遗传差异相对较大。亚群间基因分化系数（Fst）平均为 0.0722，基因流（Nm）平均为 3.214，说明不同亚群之间存在一定的基因交流。主坐标分析表明第一、二和三主成分分别解释总变异的4.97%、3.54%和3.33%。来自同一区域的品种资源基本聚集在同一亚群，聚类分析同样表明同一自然地域亚群品种资源虽不能完全聚集到同一个遗传类群中，但具有一定的聚集效应，说明川渝大豆品种资源遗传变异与地理位置有一定的关系。分子方差分析表明亚群内变异占总变异的97%，亚群间变异仅占总变异的3%。Mantel收敛分析表明地方品种自然地域亚群的遗传距离与所处的地理位置距离（纬度和海拔）呈显著的正相关关系（R2=0.723）。川渝地区大豆种质资源群体遗传丰富度不高，当前的育成品种未蕴含本地区所有遗传变异。     

Reduction in cadmium accumulation in japonica rice grains by CRISPR/Cas9-mediated editing of OsNRAMP5

Cadmium (Cd) intake is harmful to human health and Cd contamination in rice grains represents a severe threat to those consuming rice as a staple food. Knockout of Cd transporters is a promising strategy to reduce Cd accumulation in rice grains. OsNRAMP5 is the major transporter for Cd and manganese (Mn) uptake in rice. Nevertheless, it is uncertain whether knockout of OsNRAMP5 is applicable to produce low Cd rice without affecting plant growth and grain yield. In this study, we adopted CRISPR/Cas9-based gene editing technology to knock out OsNRAMP5 in two japonica varieties. We generated three independent transgene-free osnramp5 mutants and investigated the effect of osnramp5 mutations on Cd accumulation and plant growth. Hydroponic experiments showed that plant growth and chlorophyll content were significantly reduced in osnramp5 mutants at low Mn conditions, and this defective growth in the mutants could be fully rescued by supply of high levels of Mn. Cd and Mn accumulation in both roots and shoots was markedly reduced in the mutants compared to that in wild-type plants. In paddy field experiments, although Cd in flag leaves and grains was greatly reduced in osnramp5 mutants, some agronomic traits including plant height, seed setting rate, and grain number per panicle were affected in the mutants, which ultimately caused a mild reduction in grain yield. The reduced plant growth in the mutants can be attributed to a marked decrease in Mn accumulation. Our results reveal that the manipulation of OsNRAMP5 should be treated with caution: When assessing the applicability of osnramp5 mutants, soil pH and soil water content in paddy fields need to be taken into consideration, since they might affect the levels of available Mn in the soil and consequently determine the effect of the mutation on grain yield.