为了探讨水稻生长素输出载体蛋白OsPIN1a与根负向光性的关系，根据GenBank数据库报道的OsPIN1a核苷酸序列，利用RTPCR技术，设计特异引物从水稻cDNA中扩增得到生长素输出蛋白基因 (OsPIN1a)。测序结果表明，OsPIN1a基因序列中GC含量达65.49%。构建该基因的GFP融合表达载体pCAMBIA1301OsPIN1a::GFP，对洋葱表皮细胞的瞬时表达分析表明，融合蛋白主要分布在细胞膜和细胞核内。以农杆菌介导法转化水稻中花11，PCR和GUS染色检测结果表明，目的基因片段已经整合到水稻基因组内；在单侧光照射下，转基因水稻种子根的负向光弯曲角度比野生型大约14.0%， 转基因植株中OsPIN1a的表达水平也显著高于野生型植株，说明OsPIN1a可能在水稻根的负向光性反应中起重要作用。
To explore the relationship between auxin efflux protein OsPIN1a and negative phototropism of rice roots, the complete open reading frame (ORF) of OsPIN1a was amplified based on the sequence deposited in GenBank by RTPCR with genespecific primers. Sequencing results show that the GC content of OsPIN1a ORF is 65.49%. The fusion expression vector pCAMBIA1301OsPIN1a::GFP containing OsPIN1a and a coding green fluorescent protein (gfp) gene was constructed and transferred into onion skin cells by the Agrobacterium tumefaciens transformation. Transient expression of the OsPIN1aGFP protein showed that the protein was mainly located on the nucleus and cell membrane. Genetic transformation of japonica rice variety Zhonghua 11 was mediated by Agrobacterium tumefaciens. Molecular detection of transformed rice plants by PCR and GUS staining showed that the target construct was integrated into the genome of rice. The negative phototropism curvature of the transformed rice root were higher than that of the wild type as well as the expression level of OsPIN1a in transformed plants, indicating that OsPIN1a probably played an important role in negative phototropism curvature of rice root.
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