|
|
Characterization Analysis and Responses to NaCl and H2O2 Stress of AtTERT in Arabidopsis thaliana |
WANG Yang1, SUN Yu-Ping1, DONG Qi1, YANG Ying1, LIU Ying1, YU Ting-Qiao2, WU Xiao-Fei2, LU Cun-Fu1, * |
1 Beijing Advanced Innovation Center for Tree Breeding by Molecular Design/National Engineering Laboratory for Tree Breeding/College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China; 2 School of Life Sciences, Peking University, Beijing 100871, China |
|
|
Abstract Telomerase is a ribonucleoprotein complex with reverse transcriptase activity in eukaryotic cells, telomerase reverse transcriptase (TERT) is the major component of telomerase. AtTERT is the first plant telomerase reverse transcriptase TERT gene cloned from Arabidopsis thaliana. In order to clarify the structure and function of AtTERT, bioinformatics tools and software were used to analyze the physicochemical properties, protein structure and functional domain of AtTERT, and the genetic relationship of TERT genes among different species. Moreover, the telomerase activity and AtTERT gene expression patterns under salt and oxidative stress were analyzed. The results showed that the AtTERT belonged to a hydrophilic protein without a signal peptide, and had no obvious transmembrane domain. There were 125 phosphorylation sites, of which 87, 28 and 10 were serine, threonine and tyrosine sites, respectively. Irregular crimps and α-helices were the major structural elements of secondary structure of AtTERT. Conserved domains were the TRBD (telomerase RNA binding motif) domain and the RT (telomerase reverse transcriptase motifs) domain. Three-dimensional structure modeling analysis revealed a 74% similarity of the main-chain conformation between AtTERT and the Tetrahymena thermophila telomerase reverse transcriptase c6d6vA. Phylogenetic analysis using the TERT protein sequences of Gramineae, Leguminosae, Liliaceae, Rosaceae, etc, revealed that TERT was highly conserved in the same plant group. For example, TERT was highly conserved in the branches of Prunus mume and P. persica (bootstrap>99), and they had a confidence index cluster of 100, and all of the above belonged to Rosaceae. The phylogentic tree constructed by TERT conforms the right phylogenetic relationships of the plant species. Leguminous plants such as Glycine max, Phaseolus vulgaris and Solanaceae plants such as Solanum lycopersicum, S. tuberosum, Nicotiana tabacum also reflected a similar situation. Furthermore, intron and exon sequence analysis was carried out using the TERT sequences from different families. It was found that the number of exons and introns of TERT from different plants were different. Functional network prediction indicated that AtTERT might interact with some important functional proteins such as the non-homologous end-joining protein 70 (Ku70), Ku80, telomerase protective protein 1a of Arabidopsis thaliana (AtPOT1a), TER1, nucleolar protein (NAP57), recombinant DNA repair protein 50 (RAD50) and suppressor with morphogenetic effect on genitalia 7 (SMG7), which involved in telomere repair or non-telomere functions. To reveal the potential non-telomere function of AtTERT, telomerase activity and AtTERT expression pattern were detected simultaneously during salt and H2O2 treatment. At 3 d of 200 mmol/L NaCl treatment, telomerase activity increased obviously. However, the telomerase activity decreased at the 7 d. Accordingly, the Arabidopsis seedlings had been whitened at the 7 d. Further, the telomerase activity increased when treated with 0.4 mmol/L H2O2, and decreased with the further increase of H2O2 concentration from 0.8 mmol/L to 2.0 mmol/L. The AtTERT expression also increased first and then decreased under salt and oxidative stress. In summary, the present research results indicated that TERT genes are highly conserved in the same group of plants. Telomerase might have non-telomeric functions, such as regulation of gene expression, and cell repair in response to abiotic stress. The results provide new reference data for further study of plant TERT structure and function.
|
Received: 24 November 2018
|
|
Corresponding Authors:
lucunfu@bjfu.edu.cn
|
|
|
|
1 冯佳佳, 孙丹丹, 王倩, 等. 2019. PH-START1调控拟南芥种子发育的功能分析[J]. 农业生物技术学报, 27(1): 1-11. (Feng J J, Sun D D, Wang Q, et al., 2019. Functional analysis of PH-START1 in regulating Arabidopsis thaliana seed development[J]. Journal of Agricultural Biotechnology, 27(1): 1-11.) 2 郭晓强. 2010. 端粒和端粒酶的发现及意义[J]. 生物学通报, 45(3): 59-61. (Guo X Q.2010. Discovery and significance of telomere and telomerase[J]. Bulletin of Biology, 45(3): 59-61.) 3 刘颖, 吴晓飞, 门璟煜, 等. 2016. 端粒酶的非端粒功能研究进展[J]. 中国细胞生物学学报, 38(5): 640-646. (Liu Y, Wu X F, Men J Y, et al., 2016. Research progress of non-telomeric functions of telomerase[J]. Chinese Journal of Cell Biology, 38(5): 640-646.) 4 宋子仪, 杨浩, 高倩, 等. 2013. 一种高效细胞永生化载体的构建及其功能分析[J] 农业生物技术学报, 21(8): 984-992. (Song Z Y, Yang H, Gao Q, et al., 2013. Construction and functional analysis of a vector for cell immortalization with high-efficiency[J]. Journal of Agricultural Biotechnology, 21(8): 984-992.) 5 孙丽春, 杨颖, 于婷乔, 等. 2018. 沙冬青端粒酶逆转录酶基因(AmTERT)克隆及表达分析[J]. 中国细胞生物学学报, 40(7): 1088-1100. (Sun L C, Yang Y, Yu T Q, et al.2018. Cloning and expression analysis of telomerase reverse transcriptase (AmTERT) gene from Ammol/Lopiptanthus mongolicus[J]. Chinese Journal of Cell Biology, 40(7): 1088-1100.) 6 万向, 马跃, 曹立亭, 等. 2010. 端粒的功能结构与调控的研究进展[J]. 广东畜牧兽医科技, 35(5): 7-9. (Wan X, Ma Y, Cao L T, et al.2010. Advances in research on function, structure and regulation of telomeres[J]. Guangdong Journal of Animal and Veterinary Science, 35(5): 7-9.) 7 王瑾瑜, 张徐俞, 王雅群, 等. 2012. 用改进的TRAP法测定树木端粒酶活性[J]. 应用与环境生物学报, 18(4): 682-686. (Wang J Y, Zhang X Y, Wang Y Q, et al.2012. Detection of tree telomerase activity by a modified TRAP assay method[J]. Chinese Journal of Applied and Environmental Biology, 18(4): 682-686.) 8 王淑燕, 张霞, 霍金龙, 等. 2018. 版纳微型猪近交系PPP2CA克隆、表达及蛋白质功能生物信息学分析[J] 农业生物技术学报, 26(10): 1737-1746. (Wang S Y, Zhang X, Huo J L, et al., 2018. Cloning, expression and protein functional bioinformatics analysis of PPP2CA from Banna Mini-pig (Sus scrofa) inbred line[J]. Journal of Agricultural Biotechnology, 26(10): 1737-1746.) 9 张徐俞, 王瑾瑜, 郑广顺, 等. 2014. 盐胁迫下沙冬青细胞端粒酶活性的变化与DNA稳定性的关系[J]. 生物技术通报, (10): 134-138. (Zhang X Y, Wang J Y, Zheng G S, et al. 2014. Effects of aalt stress on telomerase activity in relation to DNA stability of Ammopiptanthus mongolicus cells[J]. Biotechnology Bulletin, (10): 134-138.) 10 Ahmed S, Passos J F, Birket M J, et al.2008. Telomerase does not counteract telomere shortening but protects mitochondrial function under oxidative stress[J]. Journal of Cell Science, 121(Pt 7): 1046-1053. 11 Ale-Agha N, Dyballa-Rukes N, Jakob S, et al.2014. Cellular functions of the dual-targeted catalytic subunit of telomerase, telomerase reverse transcriptase-Potential role in senescence and aging[J]. Experimental Gerontology, 56(4): 189-193. 12 Amiard S, Olivier M, Allain E, et al.2014. Telomere stability and development of ctc1 mutants are rescued by inhibition of EJ recombination pathways in a telomerase-dependent manner[J]. Nucleic Acids Research, 42(19): 11979. 13 Beenstock J, Mooshayef N, Engelberg D.2016. How do protein kinases take a selfie (autophosphorylate)?[J]. Trends in Biochemical Sciences, 41(11): 938-953. 14 Blackburn E H, Greider C W, Szostak J W.2006. Telomeres and telomerase: The path from maize, tetrahymena and yeast to human cancer and aging[J]. Nature Medicine, 12(10): 1133-1138. 15 Chiodi I, Mondello C.2012. Telomere-independent functions of telomerase in nuclei, cytoplasm, and mitochondria[J]. Frontiers in Oncology, 2(133): 133. 16 Cifuentesrojas C, Kannan K, Tseng L, et al.2011. Two RNA subunits and POT1a are components of Arabidopsis telomerase[J]. Proceedings of the National Academy of Sciences of the USA, 108(1): 73-78. 17 Ding D, Zhou J, Wang M, et al.2013. Implications of telomere-independent activities of telomerase reverse transcriptase in human cancer[J]. The Febs Journal, 280(14): 3205-3211. 18 Dvořáčková M, Fojtová M, Fajkus J.2015. Chromatin dynamics of plant telomeres and ribosomal genes[J]. Plant Journal for Cell & Molecular Biology, 83(1): 18-37. 19 Fitzgerald M S, Riha K, Gao F, et al.1999. Disruption of the telomerase catalytic subunit gene from Arabidopsis inactivates telomerase and leads to a slow loss of telomeric DNA[J]. Proceedings of the National Academy of Sciences of the USA, 96(26): 14813-14818. 20 Fojtová M, Kovařík A.2002. Recovery of tobacco cells from cadmium stress is accompanied by DNA repair and increased telomerase activity[J]. Journal of Experimental Botany, 53(378): 2151-2158. 21 Gordon D M, Santos J H.2010. The emerging role of telomerase reverse transcriptase in mitochondrial DNA metabolism[J]. Journal of Nucleic Acids, 1532-1540. 22 Jiang J, Wang Y, Sušac L, et al.2018. Structure of telomerase with telomeric DNA[J]. Cell, 173(5): 1179-1190. 23 Kim N W, Piatyszek M A, Prowse K R, et al.1994. Specific association of human telomerase activity with immortal cells and cancer[J]. Science, 266(5193): 2011-2015. 24 Kipling D, Cooke H J.1990. Hypervariable ultra-long telomeres in mice[J]. Nature, 347(6291): 400-402. 25 Lai A G, Pouchkinastantcheva N, Donfrancesco A D, et al.2017. The protein subunit of telomerase displays patterns of dynamic evolution and conservation across different metazoan taxa[J]. Bmc Evolutionary Biology, 17(1): 107. 26 Lai C, Mitchell J, Collins K.2001. RNA binding domain of telomerase reverse transcriptase[J]. Molecular & Cellular Biology, 21(4): 990-1000. 27 Le B S, Kase R S, Lh V D P.1991. Analysis of a giardia lamblia rRNA encoding telomere with [TAGGG]n as the telomere repeat[J]. Nucleic Acids Research, 19(20): 5790. 28 Lendvay T S, Morris D K, Sah J, et al.1996. Senescence mutants of saccharomyces cerevisiae with a defect in telomere replication identify three additional EST genes[J]. Genetics, 144(4): 1399-1412. 29 Lingner J, Hughes T R, Shevchenko A, et al.1997. Reverse transcriptase motifs in the catalytic subunit of telomerase[J]. Science, 276(5312): 561-567. 30 Mi K K, Kim W T.2018. Telomere structure, function, and maintenance in plants[J]. Journal of Plant Biology, 61(3): 131-136. 31 Nakamura T M, Cech T R.1997. Telomerase catalytic subunit homologs from fission yeast and human[J]. Science, 277(5328): 955. 32 Nardozzi J D, Lott K, Cingolani G.2010. Phosphorylation meets nuclear import: A review[J]. Cell Communication and Signaling, 8(1): 32. 33 Oguchi K, Liu H, Tamura K, et al.1999. Molecular cloning and characterization of AtTERT, a telomerase reverse transcriptase homolog in Arabidopsis thaliana[J]. Febs Letters, 457(3): 465-469. 34 Okamoto N, Yasukawa M, Nguyen C, et al.2011. Maintenance of tumor initiating cells of defined genetic composition by nucleostemin[J]. Proceedings of the National Academy of Sciences of the USA, 108(51): 20388-20393. 35 Richards E J, Ausubel F M.1988. Isolation of a higher eukaryotic telomere from Arabidopsis thaliana[J]. Cell, 53(1): 127-136. 36 Sýkorová E, Fajkus J.2012. Structure-function relationships in telomerase genes[J]. Biology of the Cell, 101(7): 375-406. 37 Watson J M, Riha K.2011. Telomeres, aging, and plants: From weeds to Methuselah-a mini-review[J]. Gerontology, 57(2): 129-136. 38 Xiao Z, Ming X, Zhou G, et al.2015. Telomerase: Atarget for therapeutic effects of curcumin and a curcumin derivative in Aβ insult in vitro[J]. Medical Science Journal of Central South China, 9(7): e101251. |
|
|
|