龙眼胚性愈伤组织LEC1基因cDNA克隆以及在体胚发生过程中的表达分析

分离克隆了龙眼(Dimocarpus longan Lour.)胚性愈伤组织Leafy Cotyledon 1(LEC1)基因,并分析该基因在龙眼体细胞胚胎(简称体胚)发生过程中的表达情况.采用RT-PCR结合RACE法及TAIL-PCR法,获得龙眼胚性愈伤组织LEC1基因的cDNA全长序列,运用生物信息学方法对该序列...     

高丝量蚕品种“洞·庭×碧·波”在我省的引进试养

为了改变我省家蚕生产品种单一的局面;充分利用我省春秋蚕期气候条件较温和,适宜饲养高丝量品种的特点;为了提高我省蚕茧的产量和品质,增强我省茧丝产品在国内外市场的竞争力。我们于1996年初从湖南省蚕桑科学研究所引进了夏秋     

龙眼TIR1和ABP1基因的克隆及其在体胚发生过程中的表达分析

AIM: To investigate the expression and the role of histone deacetylase 8 (HDAC8) in cardiac hypertrophy and the effects of valproic acid sodium (VPA, a histone deacetylase inhibitor) on the expression of HDAC8 and cardiac hypertrophy in two-kidney two-clip (2K2C) renovascular hypertensive rats. METHODS: Male SD rats were randomly divided into sham operation group, 2K2C group, high dose VPA (400 mg穔g^-1穌^-1) treatment group, low dose VPA (200 mg穔g^-1穌^-1) treatment group and candesartan (10 mg穔g^-1穌^-1) treatment group.Four weeks after surgery,the rats were intraperitoneally injected with VPA for 4 weeks. Sham operation and 2K2C rats were given vehicle for 4 weeks. All animals were sacrificed 8 weeks after surgery. The ratio of left ventricular weight to body weight (LVW/BW) was calculated and pathological changes of the myocardium were observed with HE staining. The mRNA expression of atrial natriuretic factor (ANF) and HDAC8 was examined by RT-PCR. The protein level of HDAC8 was also measured by Western blotting analysis. RESULTS: Compared with the control rats, the mRNA and protein expression of HDAC8 significantly increased in the myocardium in 2K2C rats while the mRNA and protein expression of HDAC8 was significantly decreased by VPA treatment in 2K2C rats. The mass index (as measured by LVW/BW) and cardiomyocyte cross areas were markedly increased and myocardial fibers were disordered in 2K2C rats, but these parameters were markedly reversed after treated with VPA for 4 weeks, indicating that VPA attenuated cardiac hypertrophy. Moreover, VPA also decreased the mRNA expression of ANF. CONCLUSION: HDAC8 may play an important role in cardiac hypertrophy in 2K2C renovascular hypertensive rats. VPA inhibits the expression of HDAC8 and prevents the development of cardiac hypertrophy.     

枇杷鲨烯合酶(Squalene synthase)基因的克隆及序列分析

鲨烯合酶(SQS)是枇杷三萜酸生物合成过程中的关键酶。以枇杷(Eriobotrya japonica L.)悬浮培养细胞为材料,采用RT-PCR和RACE方法分离得到枇杷鲨烯合酶Ej-SQS(Squalene synthase)基因的cDNA全长序列(GenBank,JQ294055),共1 775 bp,包含了5′非编码区为97 bp,开放阅读框为1 239 bp,3′非编码区为439 bp。该cDNA的开放阅读框推定的氨基酸序列(含412个氨基酸)与其它植物SQS具有79%~94%同源性,包含Trans_IPPS_HH保守结构域,可能属于Isoprenoid Biosynthesis enzymes,Class 1家族。为今后利用基因工程调控枇杷细胞悬浮培养物以提取目标产物奠定基础。     

广东蚕种业的发展与思考

80年代至今，广东省蚕桑生产有了较大的变化，主产蚕区经历了一个从珠江三角洲地区向粤北、粤东、粤西等地区转移，到现在主要集中在粤西地区的过程，蚕种生产也随着蚕区转移和时代的发展发生着很大的变化。     

亚热带地区高产优质家蚕品种粤枫二号（金·丰×玉·龙）的育成

采用杂交、回交和系统选育等育种方法,育成了实用品种金、玉、龙,与“八五”期间育成品种丰(东43C)组配成四元一代杂交种金·丰×玉·龙,即粤枫二号。经实验室鉴定,农村饲养及种场繁育结果表明,该品种蚕体强健、好饲养、产茧量高、茧丝质优良,原蚕容易饲养,蚕种繁殖系数高,综合经济性状优良。     

龙眼胚性愈伤组织胞浆型抗坏血酸过氧化物酶基因3''''末端序列的同源克隆

抗坏血酸过氧化物酶(ascorbate peroxidase,APX(EC1.11.1.11)),是活性氧清除的重要酶类。高等植物中的植物抗坏血酸存在多种同工酶,最大的区别在于叶绿体型和胞浆型,两者在酶学特性和核酸序列和分子机制上都有不同(Foy-er and Halliwell,1997)。至今,不少研究者进行APX各种同工     

枇杷细胞悬浮培养生产熊果酸的调控

以枇杷悬浮培养细胞的生长量及熊果酸（UA）的含量为考察指标,从蔗糖浓度、装液量、pH值、接种量、温度、光照强度、摇床转速、激素等开展培养参数的筛选。结果表明：接种量8 g/100 mL,pH6.0,蔗糖30 g/L,25 ℃,白炽灯400 lx,转速130 r/min,装液量130 mL/250 mL,MS+NAA 0.5 mg/L,15 d收获,细胞鲜重是起始的3.577倍,UA含量为34.993 mg/g DW,是自然界枇杷叶的约3.5倍。     

‘紫岩素’大花蕙兰与墨兰3个品种杂交坐果的研究

为筛选出易栽培种植开花、耐高温且抗性强的大花蕙兰新种质,开展了‘紫岩素’大花蕙兰与墨兰品种‘金咀’、‘企剑白墨’和‘企剑黑墨’的杂交研究。结果表明：正交和反交的坐果率差异较大;以‘紫岩素’为母本、墨兰作父本杂交的坐果率高,授粉后第210天,与 ‘金咀’、‘企剑白墨’和‘企剑黑墨’的杂交坐果率分别为81.5％、89.8％和78.0％;以墨兰为母本、‘紫岩素’作父本杂交时落果严重,授粉后第210天,‘金咀’、‘企剑白墨’和‘企剑黑墨’的坐果率分别只有0.0％、0.0％和10.3％;‘紫岩素’与墨兰3个品种正交和反交的果荚,其果长及果宽的生长发育曲线均呈“S”型;以‘紫岩素’为母本的各杂交组合果长于授粉后100～210 d达到最大值（≈8.70 cm）,果宽于授粉后180～210 d达到最大值（≈18.65 mm）;以‘紫岩素’为父本的各杂交组合果长于授粉后120～210 d时达到最大值(≈4.20 cm),果宽于授粉后150～210 d时达到最大值（≈8.60 mm）。     

龙眼胚性愈伤组织ACC合成酶基因（DL-ACS1）的克隆及表达分析

以龙眼(Dimocarpus longan Lour.)胚性愈伤组织为材料,采用同源克隆和RACE方法分离得到龙眼胚性愈伤组织乙烯合成限速酶DL-ACS1(1-aminocyclopropane-1-carboxylate synthase)基因的cDNA全长序列(GenBank,FJ617537),共1 817 bp,包含了5’非编码区(73 bp),开放阅读框(1 437 bp),3’非编码区(307 bp)。该cDNA开放阅读框的氨基酸序列(含478个氨基酸)与其它植物ACS具有77%～63%同源性,属于ACC Synthase家族。实时荧光定量PCR分析表明,该基因在龙眼体细胞胚胎(以下简称龙眼体胚)各阶段的表达量存在较大的时期差异,其中,球形胚(Stage 5)的表达量最高,鱼雷形胚(Stage 7)的表达量最低。