TA29-Barnase嵌合基因导入对烟草花药绒毡层及花粉发育的影响  

EFFECTS OF INTRODUCING THE CfflMAERIC GENE TA29-BARNASE ON THE TAPETUM AND POLLEN DEVELOPMENT IN TOBACCO

作　　者：罗玉英[1] 刘玉乐[2] 李胜国[2] 田波[2] 

机构地区：[1]首都师范大学生物系,北京100037 [2]中国科学院微生物研究所,北京100080

出　　处：《Acta Botanica Sinica》1997年第10期894-898,共5页Acta Botanica Sinica（植物学报：英文版）

摘　　要：比较研究了烟草(Nicotiana tabacum L.)TA29-Barnase转基因不育植株和正常植株的花药绒毡层及花粉发育的全过程。研究表明,外源基因在花药中特异表达导致绒毡层细胞的提前降解,这种降解一般在减数分裂早期开始,至四分体时期完成,而正常花药绒毡层的降解发生在二细胞雄配子体初期,至花粉发育的后期方才完成。转基因植株花药绒毡层的降解在细胞结构上表现为:最初发生细胞的液泡化,然后细胞核凝聚,最后整个细胞溃解。转基因植株的花粉母细胞则在减数分裂过程中逐渐降解、退化,只有少数花粉母细胞能够顺利完成减数分裂发育成小孢子。观察结果还表明外源基因在花药中的表达是不均一的。对转基因不育和自然败育在细胞结构上的不同表现进行了讨论。The development of tapetum and pollen in transgenic tobacco (Nicotiana tabacum L.) harboring a chimaeric gene TA29-Barnase was compared with that of the wild-type plant. The specific expression of the exogenous genes in anther led to premature tapetal degradation, which started at the early stage of meiosis and terminated at the tetrad stage. In the wild-type anthers, tapetal degradation started at the early stage of bicellular microgametophyte and ended at the later stage of pollen development. The cytological changes of tapetal degradation in the transgenic plants were characterized by vacuolization of the tapetal cells, then nuclear condensation, and consequent massive degradation of tapetal cells. Meanwhile, the pollen mother cells gradually degraded and became destroyed along with the progress of meiosis, leaving only a few which could successfully complete their meiosis to form microspores. This observation also indicated that the TA29-Barnase gene in anther was not uniformly expressed. In addition, the structural difference between the male sterility induced by exogenous gene and the natural sterile was also discussed.

关 键 词：烟草 基因工程 雄性不育 绒毡层 核酸酶基因 

分 类 号：S572.032[农业科学—烟草工业] S188[农业科学—作物学]