蓝光调节高粱突变体har1幼苗的去黄化反应  

Blue Light-mediated De-etiolation in Sorghum Mutant har1

作　　者：高苏娟[1] 谢修志[1] 陈兆平[1] 黄志刚[1] 赵琦[2] 王小菁[1] 

机构地区：[1]华南师范大学生命科学学院,广东省植物发育生物工程重点实验室,广州510631 [2]首都师范大学生命科学学院,北京100037

出　　处：《植物学报》2009年第1期69-78,共10页Chinese Bulletin of Botany

基　　金：国家自然科学基金(No.30170558);国家科技支撑计划(No.2007BAD59B06)

摘　　要：以航空诱变高粱突变体har1为材料,对其幼苗去黄化过程进行研究。萌发的种子在远红光下预培养6小时后,置于12小时蓝光/12小时黑暗条件下培养。测量幼苗的各器官伸长,结果表明,与野生型R111相比,har1的胚芽鞘、中胚轴、第一叶鞘以及第二叶鞘的伸长均受到蓝光的明显抑制,而蓝光对叶片生长影响不明显。3天龄har1黄化苗在连续蓝光下中胚轴花色素苷的积累明显增高,红光和远红光无此效应。此外,蓝光促进har1叶片叶绿体发育,且在蓝光照射24小时后叶片中叶绿素含量升高。Western blot检测结果显示,7天龄R111和har1幼苗隐花色素SbCRY1b蛋白水平呈现蓝光下低、黑暗中高的变化趋势,har1的SbCRY1b蛋白水平在黑暗中高于R111。研究结果表明,高粱har1在去黄化过程中具有蓝光超敏感表型,SbCRY1b的作用值得进一步深入研究。Sorghum is an important food, feed and biofuel crop with ＂C4＂ photosynthesis. Understanding the mechanisms of sorghum growth and development regulated by light can help in molecular breeding to improve quality and better reveal the biochemical and morphological specifications. The present study used a Chinese home-made reversal satellite system to investigate blue light （BL）-mediated de-etiolation in the sorghum harl mutant. The seeds of both the wild-type Rlll and harl mutant were germinated and pre-cultured under 1.8 μmol.m^-2.s^-1 far-red light for 6 h, then irradiated with BL under 12-h light （20 μmol.m^-2.s^-1）/12-h dark conditions. The young seedlings of harl showed shorter coleoptiles and mesocotyls and inhibited growth than the wild type 2 to 3 d after BL irradiation. Elongation of the leaf sheath was inhibited as well. The first and second leaf sheaths showed 25% to 48% inhibition in length as compared with that of Rl11, but leaf blades had similar lengths. Moreover, the anthocyanin accumulation in mesocotyls of 3-d-old harl seedlings was remarkably higher than that of Rlll after continuous BL irradiation; red and farred light had no significant effect on pigmentation. Plastids developed in 3-d-old har1 leaves during de-etiolation, with more developed grana. The content of chlorophyll in harl seedlings was higher than that of Rlll seedlings after 24-h BL irradiation.Immunoblot analysis with anti-SbCRYlb antibody showed SbCRYlb expressed in both Rlll and harl mesocotyls of 7-d-old seedlings grown under 12-h BL/12-h dark. Seedlings of the har1 mutant showed higher accumulation of SbCRYlb in darkness. Our results suggest that har1 is hypersensitive to BL during de-etiolation. The role of SbCRY1b in the BL-mediated response of har1 remains to be elucidated.

关 键 词：蓝光 隐花色素 去黄化 突变体 高粱 

分 类 号：S514[农业科学—作物学]