title: Development of insect-resistant transgenic rice with Cry1C*-free endosperm.
abstract: BACKGROUND
  Yellow stem borer (Tryporyza incertulas Walker), striped stem borer (Chilo suppressalis Walker) and leaf folder (Cnaphalocrocis medinalis Guenec) are three lepidopteran pests that cause severe damage to rice in many areas of the world. In this study, novel insect-resistant transgenic rice was developed in which Bt protein expression was nearly absent in the endosperm. The resistant gene, cry1C*, driven by the rice rbcS promoter (small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase), was introduced into Zhonghua 11 (Oryza sativa L. ssp. japonica) by Agrobacterium-mediated transformation.
  
  
  RESULTS
  A total of 83 independent transformants were obtained, 19 of which were characterised as single-copy foreign gene insertion. After preliminary screening of the T(1) families of these 19 transformants in the field, six highly insect-resistant homozygous lines were selected. These six homozygous transgenic lines were field tested for resistance to leaf folders and stem borers, and for their agronomic performance. The Cry1C* protein levels in leaves and endosperm were measured by ELISA. Subsequently, the elite transgenic line RJ5 was selected; this line not only possessed high resistance to leaf folders and stem borers, normal agronomic performance, but also Cry1C* expression was only 2.6 ng g(-1) in the endosperm.
  
  
  CONCLUSIONS
  These results indicated that RJ5 has the potential for widespread utility in rice production.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Rongjian
authors.initials: R
authors.lastname: Ye
authors.forename: Haiqun
authors.initials: H
authors.lastname: Huang
authors.forename: Zhou
authors.initials: Z
authors.lastname: Yang
authors.forename: Taiyu
authors.initials: T
authors.lastname: Chen
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Xianghua
authors.initials: X
authors.lastname: Li
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Lin
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004731:Endotoxins / Q000235:genetics / Q000378:metabolism*; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism*; D007313:Insecta / Q000502:physiology*; D012275:Oryza / Q000235:genetics / Q000469:parasitology / Q000502:physiology*; D010935:Plant Diseases / Q000469:parasitology*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000469:parasitology / Q000502:physiology*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis