Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: The ACR11 encodes a novel type of chloroplastic ACT domain repeat protein that is coordinately expressed with GLN2 in Arabidopsis | Sung et al. BMC Plant Biology 2011 11 118 http 1471-2229 11 118 BMC Plant Biology RESEARCH ARTICLE Open Access The ACR11 encodes a novel type of chloroplastic ACT domain repeat protein that is coordinately expressed with GLN2 in Arabidopsis Tzu-Ying Sung Tsui-Yun Chung Chih-Ping Hsu and Ming-Hsiun Hsieh Abstract Background The ACT domain named after bacterial aspartate kinase chorismate mutase and TyrA prephenate dehydrogenase is a regulatory domain that serves as an amino acid-binding site in feedback-regulated amino acid metabolic enzymes. We have previously identified a novel type of ACT domain-containing protein family the ACT domain repeat ACR protein family in Arabidopsis. Members of the ACR family ACR1 to ACR8 contain four copies of the ACT domain that extend throughout the entire polypeptide. Here we describe the identification of four novel ACT domain-containing proteins namely ACR9 to ACR12 in Arabidopsis. The ACR9 and ACR10 proteins contain three copies of the ACT domain whereas the ACR11 and ACR12 proteins have a putative transit peptide followed by two copies of the ACT domain. The functions of these plant ACR proteins are largely unknown. Results The ACR11 and ACR12 proteins are predicted to target to chloroplasts. We used protoplast transient expression assay to demonstrate that the Arabidopsis ACR11- and ACR12-green fluorescent fusion proteins are localized to the chloroplast. Analysis of an ACR11 promoter-p-glucuronidase GUS fusion in transgenic Arabidopsis revealed that the GUS activity was mainly detected in mature leaves and sepals. Interestingly coexpression analysis revealed that the GLN2 which encodes a chloroplastic glutamine synthetase has the highest mutual rank in the coexpressed gene network connected to ACR11. We used RNA gel blot analysis to confirm that the expression pattern of ACR11 is similar to that of GLN2 in various organs from 6-week-old Arabidopsis. Moreover the expression of ACR11 and GLN2 is highly .
