以拟南芥菜(Arabido psis thaliana)基因组DNA为模板，通过PCR扩增得到绒毡层特异表达基因A9的启动子片段，克隆到pUCl8载体上。序列分析表明，该启动子大小为360bp，RNA聚合酶识别序列TATA box，花药特异表达和增强序列TGTGG、TGTGA两个Motifs皆完整，与已报道的序列比较仅有3个核苷酸发生改变，同源性为99．2％。该启动子与GUS基因融合后用基因枪转化玉米花药，荧光分析显示花药中有GUS酶活性存在。%The upstream regulatory region of the tapetal-specific gene A9 was amplified from Arabidopsis thaliana genome by polymerase chain reaction and cloned into HincⅡ and Kpn Ⅰ site of pUCl8．Sequence analysis showed that the cloned fagment contained 364 nucleotides，and shared a sequence homology of 99．2％with the reported A9 promoter.The putative TATA box was present at posidon —76 to —69．Two motifs，TGTGG and TGTGA，which were considered to be responsible for the specificity and enhancement of gene expression in the tapetal，were fOund within—291 to—287 and—243 to—239 regionrectively．Gene construct thatcontained the β-glucuronidase(GUS)gene under the control of A9 promoter or CaMV35s promoter was introduced into anthers and calli of maize by particle bombardmend．The GUS activity was detected only in anthers by fluorometric assay．
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