青花菜β—1，4—木糖基轉移酶IRX9H基因的克隆及在模擬酸雨脅迫下的表達分析

高世超等

摘 要 由糖基轉移酶催化產生的次生代謝物質對植物抵御和適應環境的變化起著重要作用。為探討青花菜在酸雨脅迫下糖基轉移酶的表達變化，對青花菜β-1，4-木糖基轉移酶IRX9H基因的cDNA序列全長進行克隆，并對其進行生物信息學和表達分析。結果表明：青花菜β-1，4-木糖基轉移酶IRX9H基因的cDNA全長為1 550 bp，開放閱讀框為1 155 bp，編碼384個氨基酸，推測分子式為C1964H3044N558O567S11，分子量為43 897.8，沒有信號肽。系統進化樹分析結果表明，該青花菜基因與擬南芥聚類關系最近。利用實時熒光定量PCR研究模擬酸雨脅迫下β-1， 4-木糖基轉移酶IRX9H基因的表達量，結果顯示該基因的表達量在模擬酸雨脅迫初期顯著增大，隨著時間的延長，又開始下降，這表明其在青花菜抗酸雨脅迫中發揮了作用。

關鍵詞 青花菜；β-1， 4-木糖基轉移酶IRX9H基因；分子克隆；模擬酸雨；表達

中圖分類號 S635.3 文獻標識碼 A

Cloning of β-1， 4 - xylosyltransferase IRX9H in Broccoli

（Brassica oleracea var. italica） and Its Expression

in Broccoli Under Simulated Acid Rain Stress

GAO Shichao， ZHONG Fenglin*， LIN Yizhang， ZHAO Ruili， LIN Junfang， YE Liping

College of Horticulture， Fujian Agriculture and Forestry University， Fuzhou， Fujian 350002， China

Abstract Secondary metabolites catalyzed by glycosyltransferase played an important role in resisting and adapting to environmental changes for plants. The full-length cDNA of β-1，4-xylosyltransferase IRX9H was cloned in order to explore its expression in broccoli under acid rain stress， which was analyzed by bioinformatics method and real-time PCR. The results showed that the full-length DNA was 1 550 bp and the opening reading frame（ORF）was 1 155 bp. The ORF encoded 384 amino acids， a deduced formula of C1964H3044N558O567S11 with molecular weight 43 897.8， but no signal peptide. Phylogenetic tree analysis revealed that the gene of broccoli had closer relationship with that from Arabidopsis. The analysis by real-time PCR suggested that the expression of β-1，4-xylosyltransferase IRX9H genes in broccoli under simulated acid rain stress increased significantly at first，and then declined due to longer duration of simulated acid rain stress， which was involved in signalling pathways in response to the acid rain stress.

Key words Brassica oleracea；β-1，4-xylosyltransferase IRX9H；Molecular cloning；Simulated acid rain； Expression

doi 10.3969/j.issn.1000-2561.2014.04.020

青花菜（Brassica oleracea var. italica）又名青花椰菜、意大利花菜、意大利芥藍、木立花椰菜、綠花菜、莖椰菜、西蘭花，屬于十字花科蕓薹屬一、二年生草本植物。甘藍種中以綠花球為產品的一個變種，以主莖及側枝頂端形成的綠色花球為產品，其營養豐富，色、香、味具佳，具有抗氧化、抗病毒、助消化和抗衰老等作用[1-5]，是國際市場十分暢銷的一種名特蔬菜。近年來，東亞地區己經成為繼歐洲和北美之后的第三大酸雨區，且受影響面積有快速增加的趨勢，致使酸雨己經成為中國最重要的環境問題之一[6]。已有大量研究結果表明，酸雨會破壞蔬菜的正常生長發育，從而降低蔬菜產量[7-11]。……