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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 whole process of anther tapetum and pollen development of tobacco plants (Nicotiana tabacum L.) TA29-Barnase transgenic sterile plants and normal plants was comparatively studied. Studies have shown that the specific expression of exogenous genes in anther leads to the early degradation of tapetal cells, which usually begins early in meiosis and completes in tetrad, whereas the degradation of normal anther tapetum occurs in two cells Male gametophyte early, to the late pollen development had just completed. The degradation of the anther tapetal in the transgenic plants is manifested in the cellular structure as the initial vacuolization of the cells followed by the condensation of the nuclei and finally the breakdown of the entire cell. The pollen mother cells of transgenic plants gradually degrade and degenerate during meiosis. Only a few pollen mother cells successfully perform meiosis and develop into microspores. The observations also indicate that the expression of foreign genes in anthers is not uniform. The different manifestations of cell structure in transgenic sterile and spontaneous abortion were discussed.