Abstract: The 1941-bp full cDNA sequence (GenBank No. DQ839506) of LSU I, the cytoplasmic large subunit gene I of adenosine 5’ diphosphate glucose pyrophosphorylase (AGPase), was cloned from a high 1000-grain weight wheat (Triticum aestivum L.) cultivar Yujiao 2. Semi-quantitive PCR analysis showed that LSU I expressed higher in leaves, glumes, sheaths, and grain than in roots and stems, indicating that LSU I expressed actively in photosynthetic and starch synthesis-related organs. During the primal period of grain development (5–10 d after thesis), there was no difference in transcript levels of LSU I gene between Yujiao 2 and Lankao Aizao 8 (low 1000-grain weight), but the transcript amounts in grains of Yujiao 2 was markedly higher than that of Lankao Aizao 8 at grain filling and maturity stages. The changes of LSU I gene expression were similar to the trend of starch accumulation in the two cultivars, suggesting that LSU I gene may be associated with starch accumulation in common wheat.

Key words: Triticum aestivum L., Cytoplasmic large subsuit gene I of AGPase, Gene cloning, RT-PCR, Gene expression