野生大豆（Glycine soja）是世界上種植面積最廣的作物之一。相比于栽培大豆，野生大豆能夠更好地適應自然環境的脅迫如干旱，堿，鹽脅迫。對野生大豆的性狀進行系統研究，將有助于栽培大豆的遺傳改良。近日，華南農業大學亞熱帶農業生物資源保護與利用國家重點實驗室年海教授領銜的課題組聯合使用第二代高通量測序技術對鋁脅迫下野生大豆miRNA及其靶基因進行鑒定和系統分析，新發現了一批的野生大豆miRNA和其作用的靶基因*。該研究成果發表在10月刊的BMC Plant Biology上。
MicroRNA（miRNA）是一類調控真核生物廣泛生理過程的內源性非編碼小RNA，它的調控作用是通過降解靶mRNA或是阻礙其翻譯來實現。植物miRNA通常與其靶基因完全或是近乎完全匹配，引起mRNA的降解。在植物中，miRNA參與調控發育全過程以及對生物或非生物脅迫的應答。要確定miRNA的功能就必須首先鑒定它們的靶基因。降解組測序是近來興起的一種高效的大規模鑒定植物miRNA靶基因的方案。
年海教授課題組以鋁處理和無鋁處理的野生大豆幼苗根為對象，構建了兩個小RNA測序文庫和兩個降解組測序文庫。利用miRNA測序發現野生大豆中97個已知miRNA和31個新的miRNA。此外，還發現49個已知miRNA對應的3P或5P鏈上的miRNA。在所有被鑒定的miRNA中，30個miRNA的表達與鋁脅迫相關。進一步利用降解組測序，作者鑒定出已知miRNA的86個靶基因和測序發現miRNA的5個靶基因。GO富集分析結果顯示52個保守miRNA家族的靶基因在轉錄調控中扮演著重要角色。同時還發現，一些與脅迫應答相關的基因如生長素響應因子（ARF）在鋁脅迫條件下被miRNA剪切。
此項研究聯合使用miRNA測序和降解組測序技術大規模系統地測定了鋁脅迫下野生大豆的miRNA表達譜和靶基因及其功能，為深入理解鋁脅迫下miRNA發揮的調控作用提供了重要信息。
此項研究中的小RNA測序和降解組測序工作是由聯川生物公司提供技術服務。
* Zeng QY, Yang CY, Ma QB, Li XP, Dong WW, Nian H. (2012) Identification of wild soybean miRNAs and their target genes responsive to aluminum stress. BMC Plant Biol 12(1), 182.
聯川生物小RNA測序和降解組測序用戶近期發表文章索引
l Li, M. et al. (2012) An atlas of DNA methylomes in porcine adipose and muscle tissues. Nat Commun 3, 850.
l Zhai L, Liu Z, Zou X, Jiang Y, Qiu F, Zhengand Y, Zhang Z. (2012) Genome-wide identification and analysis of microRNA responding to long-term waterlogging in crown roots of maize seedlings. Physiologia Plantarum [Epub ahead of print].
l Zeng QY, Yang CY, Ma QB, Li XP, Dong WW, Nian H. (2012) Identification of wild soybean miRNAs and their target genes responsive to aluminum stress. BMC Plant Biol 12(1), 182.
l Xu MY, Dong Y, Zhang QX, Zhang L, Luo YZ, Sun J, Fan YL, Wang L. (2012) Identification of miRNAs and their targets from Brassica napus by high-throughput sequencing and degradome analysis. BMC Genomics 13:421.
l Huang T, Xu D, Zhang X. (2012) Characterization of host microRNAs that respond to DNA virus infection in a crustacean. BMC Genomics 13(1), 159.
l Yang G, Yang L, Zhao Z, Wang J, Zhang X (2012) Signature miRNAs Involved in the Innate Immunity of Invertebrates. PLoS ONE 7(6), e39015.
l Li R, Sun Q, Jia Y, Cong R, Ni Y, et al. (2012) Coordinated miRNA/mRNA Expression Profiles for Understanding Breed-Specific Metabolic Characters of Liver between Erhualian and Large White Pigs. PLoS ONE 7(6), e38716.
l Mao W, Li Z, Xia X, Li Y, Yu J. (2012) A Combined Approach of High-Throughput Sequencing and Degradome Analysis Reveals Tissue Specific Expression of MicroRNAs and Their Targets in Cucumber. PLoS One 7(3), e33040
l Zhao M, Tai H, Sun S, Zhang F, Xu Y, et al. (2012) Cloning and Characterization of Maize miRNAs Involved in Responses to Nitrogen Deficiency. PLoS ONE 7(1), e29669.
l Zhang J, Zhang S, Han S, Wu T, Li X, Li W, Qi L. (2012) Genome-wide identification of microRNAs in larch and stage-specific modulation of 11 conserved microRNAs and their targets during somatic embryogenesis. Planta. [Epub ahead of print]
l Zhou Q, Li M, Wang X, Li Q, Wang T, Zhu Q, Zhou X, Wang X, Gao X, Li X. (2012) Immune-related MicroRNAs are Abundant in Breast Milk Exosomes. Int J Biol Sci 8(1), 118-123.
l Li B, Qin Y, Duan H, Yin W, Xia X. (2011) Genome-wide characterization of new and drought stress responsive microRNAs in Populus euphratica. J Exp Bot 62(11), 3765-79.