Agrobacterium-mediated transformation of two rice varieties with AtMyb61 gene for lignin content manipulation towards biomass refinery Syamsidah Rahmawati*, Carla Frieda Pantouw, Amy Estiati, Budi Satrio, Dwi Widyajayantie, Dwi Astuti, Agus Rachmat, Vincentia Esti Windiastri, Ade Nena Nurhasanah, Yuli Sulistyowati and Satya Nugroho**
Research Centre for Biotechnology, Indonesian Institute of Sciences
Jl. Raya Bogor KM 46 CSC-BG
*syamsidahrahmawati[at]gmail.com
**nugroho_satya[at]gmail.com
Abstract
The Atmyb61 gene plays an important role in lignin biosynthesis. Lignin is potentially used for renewable chemicals and biomaterials. This study was aimed to modify the lignin content of two rice varieties Nipponbare (ssp Japonica) and Rojolele (ssp Javanica). The AtMyb61 gene under the control of a strong constitutive promoter CaMV 35S was transformed into those rice varieties mediated by the Agrobacterium tumefaciens strain LBA 4404. From this Agrobacterium transformation, a total of 192 putative transgenic plants were obtained, of which 85 and 18 putative transgenic plants for Nipponbare and Rojolele, respectively. The highest regeneration efficiency (57.73%) and transformation efficiency (10.20%) was obtained from rice cv Nipponbare. Meanwhile, regeneration and transformation efficiency of rice cv Rojolele was, consecutively, almost two times (28.93%) and four times (2.25%) lower than that of rice cv Nipponbare. In planta HPT leave assay showed that 85 (68.55%) and 18 (26.47%) plants of rice cv Nipponbare and Rojolele, respectively, expressed hygromycin phosphotransferase indicated that the rice plants positive contained inserted genes. Further evaluation on the expression of rice genes related to lignin biosynthesis, lignin content, and other physiological and agronomical characters will be carried out.
