MdMYB73的分子克隆及其在苹果愈伤组织和拟南芥幼苗中的盐抗性功能鉴定

从‘嘎拉’苹果中克隆了一个MYB转录因子基因(序列号:MDP0000894463)。该基因包含长为729 bp完整的开放阅读框,编码243个氨基酸,预测其蛋白质分子量为26.34 kD,等电点为9.29。系统进化树分析表明,这一MYB转录因子与拟南芥AtMYB73同源序列相似性最高,因此将其命名为MdMYB73。功能域分析表明,MdMYB73蛋白含有保守的R2R3-typeMYB绑定域。荧光定量PCR分析表明,MdMYB73在苹果的各个组织均有表达,在叶片和花中表达相对较高;MdMYB73的表达明显受盐胁迫的诱导。将异位表达MdMYB73的拟南芥幼苗进行抗盐鉴定,结果表明MdMYB73负调控拟南芥盐胁迫抗性;同时,AtSOS1,AtSOS3和AtNHX1抗盐相关基因的表达水平显著降低,表明MdMYB73可能负调控SOS反应,影响拟南芥抵抗高盐胁迫过程。将MdMYB73基因遗传转化苹果愈伤组织,抗盐表型分析表明,MdMYB73过量表达也明显降低了转基因愈伤组织对盐胁迫的抗性。     

DNA去甲基化参与提高白菜型冬油菜抗寒性的生理机制

利用来自不同育种环境的10份白菜型冬油菜材料,通过半致死温度的测定分析其抗寒性与环境的关系,并利用不同浓度DNA甲基化抑制剂5-azaC处理,分析DNA去甲基化对白菜型冬油菜DNA整体甲基化水平及低温胁迫下苗期生理特性的影响。结果表明,不同育种环境选育的材料,其半致死温度具有显著差异,其中材料2018-FJT、DT-7、DT-9与MXW-1的半致死温度分别为-16.04℃、-15.98℃、-15.63℃、-15.04℃;材料CT-2360、CT-2380、CT-2400、CT-2420、CT-2440、CT-2460的半致死温度分别为-11.32℃、-11.6℃、-11.42℃、-11.44℃、-12.97℃、-13.28℃。依据半致死温度,10个白菜型冬油菜抗寒性由强到弱依次为:2018-FJTDT-7DT-9MXW-1CT-2460CT-2400CT-2380CT-2420CT-2440CT-2360。抗寒性的形成与育成环境的纬度和年平均气温呈极显著正相关。选择抗寒性及产地不同的4个材料CT-2360、MXW-1、2018-FJT、DT-7进行生理测定,结果表明,1 000μmol·L~(-1) 5-azaC处理能显著抑制幼苗的根生长,4个材料的根长较对照减少93.14%～95.06%;低温下5-azaC处理对抗寒性较弱材料CT-2360幼苗的相对电导率、丙二醛含量以及强抗寒性材料DT-7幼苗的脯氨酸、可溶性蛋白含量影响最显著(P0.05);低温处理过程中,4个材料的SOD、POD、CAT活性均上升,以低温处理5d最显著(P0.05),其中2018-FJT的SOD活性增幅最高,为45.85%,DT-7的POD活性增幅最大,为460%,CT-2360的CAT活性增幅最显著,为321.02%。HPLC分析发现常温下抗寒性较弱材料CT-2360的甲基化水平为77.48%,高于其他3个抗寒性强的材料;经过5-azaC处理后发生明显的去甲基化作用,证明抗寒能力受DNA去甲基化的调控。     

盆栽灵武长枣设施促早栽培的需冷量研究

以盆栽灵武长枣为试验材料,利用保鲜冷库在2℃条件下对盆栽灵武长枣进行冷藏,强制其休眠,将经过20～65 d共10个冷藏时间处理的盆栽灵武长枣移至日光温室升温催芽,通过分析不同冷藏时段下盆栽灵武长枣的萌芽率,确定其需冷量.研究结果显示,在0～7.2℃范围内,随着冷藏时间增加,盆栽灵武长枣的萌芽率也在增加,萌芽率与冷藏时间...     

不同光质对喜树愈伤组织形成及分化潜质影响

以喜树无菌苗的茎、叶为外植体,研究了蓝、白、红3种光质下,MS、1/2MS、SH、WPM4种培养基对喜树愈伤组织形成及分化潜质影响。结果表明:蓝光下SH+1.0mg/L NAA+0.075mg/L TDZ培养基上愈伤组织诱导效果最好;愈伤组织继代后在蓝光下第7天时,SOD酶活最高,POD酶活最低,含水量最低,分化的潜力最大。     

辣椒CaCOI1 基因的克隆、表达及其序列分析

 利用RT-PCR技术从辣椒中克隆到基因CaCOI1,该基因编码的蛋白质由603个氨基酸残基组成,蛋白质的分子量为68.35 kD,等电点是6.32。在蛋白质N–端有1个F-box结构域,C–端有6个富含亮氨酸结构域。二级结构分析表明,CaCOI1蛋白分子中,α–螺旋、β–折叠、β–转角和不规则卷曲分别为51.41%、13.76%、5.80%和29.03%。CaCOI1蛋白的平均亲水系数为–0.143,为亲水蛋白。蛋白质序列比对和进化树分析表明,CaCOI1与番茄LeCOI1蛋白的一致性最高（94%）,进化距离最近。实时定量RT-PCR分析表明,CaCOI1在辣椒的根、茎、幼叶、成熟叶、花、青熟期果实、成熟红果等不同生长发育时期的组织中都能表达,在花中表达水平最高,是其他组织的2.8 ~ 5.4倍,表明CaCOI1在花的发育过程中起重要作用。     

Mechanism of Chinese processing in patients with Broca aphasia

AIM: To explore the mechanism of Chinese processing in patients with Broca aphasia so as to offering accordance for speech rehabilitation. METHODS: The test of orthographic, semantic information and phonological were conducted. The scores in each group with Chi-square test in patients were compared to those in 10 normal people. RESULTS: No significant difference between two groups in the vocabulary identification and in the vocabulary identification from homophony (P>0.05) was observed (P>0.05). There was significant difference in the identification picture from vocabularies, the identification vocabulary from pictures and the vocabulary identification from sound (P>0.05). CONCLUSION: The patient with Broca aphasia is independent in the course of the orthographic input, and the ability to retrieve semantic information from orthographic activation word may not affected by phonological lexicon.     

重庆开县3个锦橙品种留树贮藏试验初报

对重庆市开县3个锦橙品种留树贮藏效果进行探索,结果表明,‘开陈72-1’、‘开盛76-8’和‘北碚447’3个锦橙品种留树贮藏至2月下旬,能维持较高的坐果率、商品果率、外观色泽和可溶性固形物含量;‘开陈72-1’最适宜做开县锦橙留树贮藏品种。     

无子沙糖橘(十月橘)的选育

采用芽变选种的方法,在四会市石狗镇选出了无子柑橘新品种—无子沙糖橘(十月橘)。果略小,单果重平均40g左右,单果平均种子数0.5粒以内,达到柑橘无子的标准。果实扁平,皮橘红色,薄而脆;果肉橙黄色,味清甜,可溶性固形物13%以上,肉质爽脆化渣,品质上等。早结丰产性好,发梢能力强,3月上中旬开花,12月上旬果实开始成熟。     

Effects of baicalin on CA46 cell xenografts in nude mice

AIM: To study the effects of baicalin on CA46 cell xenografts in nude mice. METHODS: The nude mice with CA46 cell xenografts were treated with drugs via intraperitoneal injection daily, and were divided into 5 groups: negative control group, 15 mg/kg baicalin group, 30 mg/kg baicalin group, 60 mg/kg baicalin group and 4 mg/kg etoposide (VP-16) positive control group. After 12-day treatment, the weight of CA46 cell xenografts stripped from some nude mice in the 5 groups was used to evaluate the effect of baicalin on xenograft growth in the nude mice. The apoptosis, necrosis and pathological changes of the xenograft cells were examined under light microscope and transmission electronic microscope respectively. The expression levels of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway-related proteins extracted from xenografts were determined by Western blotting. The other nude mice with CA46 cell xenografts in the 5 groups continued to be treated with the drugs until death in order to evaluate the effect of balcalin on survival time of the nude mice with CA46 cell xenografts. RESULTS: Baicalin remarkably inhibited the growth of CA46 cell xenografts, induced apoptosis and necrosis of xenograft cells, and reduced the protein expression of phospho-Akt (p-Akt), nuclear factor-kappa B (NF-κB), mammalian target of rapamycin (mTOR) and phospho-mTOR (p-mTOR) in the xenografts after 12-day treatment. Furthermore, baicalin prolonged the survival time of the nude mice with CA46 cell xenografts in a dose-dependent manner. CONCLUSION: Baicalin inhibits the growth and induces apoptosis of CA46 cell xenografts in the nude mice, and prolongs the survival time of the nude mice with CA46 cell xenografts through the mechanism of down-regulating PI3K/Akt/NF-κB and PI3K/Akt/ mTOR signaling pathways.     

白莲腐败病病原菌的分离鉴定

莲腐败病是白莲种植区发生最普遍、为害最严重的病害之一。本试验对发病白莲上的病原茵进行分离鉴定。该病原分离物在PSA培养基上气生茵丝由白色渐变成深紫色,并产生大小两种孢子。大型分生孢子镰刀形,无色,稍呈弯曲,两端尖细,大小为（39．1-55．2）μm×（2．8～4．6）p,m,多为3个隔膜,少部分为1-2隔或4~5隔;小型分生孢子椭圆形。无色,无隔膜,大小为（5．0～9．2）μm×（2．0～3．5）μm。致病性测定表明分离物能100％引起白莲出现典型的白莲腐败病的症状。ITSl／ITS4的PCR扩增产物与GenBank中Fusariumoxysporum￡sp．nelumbicola的序列同源性为99％。研究结果表明。分离到的病原物为尖孢镰刀茵莲专化型Foxysporum f.sp．ndumbicola。