近日，中科院植物研究所馬慶虎研究組通過(guò)對(duì)木質(zhì)素代謝與基因表達(dá)分析,，揭示了木質(zhì)素合成與小麥抗倒伏之間的關(guān)系，并定位了與抗倒伏相關(guān)的木質(zhì)素基因,。該成果發(fā)表在Journal of Experimental Botany（2009, 60: 2763–2771）雜志上,。
小麥的倒伏是影響其穩(wěn)產(chǎn)高產(chǎn)的一個(gè)重要因素。倒伏是一個(gè)由生理,、遺傳,、栽培和環(huán)境等多因素調(diào)控的數(shù)量性狀，對(duì)其分子水平的調(diào)控機(jī)理尚需要深入的研究,。在農(nóng)業(yè)生產(chǎn)上，通過(guò)矮化基因的開發(fā)和育種曾經(jīng)有效地緩解了小麥倒伏危害的發(fā)生,，但是隨著株高的降低會(huì)影響小麥生物產(chǎn)量的潛力,，因此通過(guò)增強(qiáng)莖稈強(qiáng)度，在不降低株高的情況下提高小麥的抗倒伏特性對(duì)開發(fā)高產(chǎn)小麥具有重要意義,。木質(zhì)素是植物細(xì)胞壁中起機(jī)械支持的重要高分子物質(zhì),。馬慶虎研究組分離了在小麥莖稈中高度表達(dá)的木質(zhì)素合成關(guān)鍵酶基因—咖啡酸甲基轉(zhuǎn)移酶基因（COMT），通過(guò)生化和轉(zhuǎn)基因分析證明COMT 在控制松柏醇型木質(zhì)素上發(fā)揮著重要作用,，COMT基因的表達(dá)在抗倒伏小麥生長(zhǎng)發(fā)育后期明顯高于易倒伏品種,，這種基因的高表達(dá)進(jìn)一步促進(jìn)了COMT酶蛋白和酶活力的提高，并增強(qiáng)了木質(zhì)素的合成,。小麥的COMT基因定位在3B染色體上。
該研究成果對(duì)闡明木質(zhì)素代謝與倒伏關(guān)系,，并通過(guò)調(diào)控木質(zhì)素代謝培育抗倒伏的高產(chǎn)超級(jí)小麥具有重要意義,。（生物谷Bioon.com）
生物谷推薦原始出處：
Journal of Experimental Botany 2009 60(9):2763-2771; doi:10.1093/jxb/erp132
The expression of caffeic acid 3-O-methyltransferase in two wheat genotypes differing in lodging resistance
Qing-Hu Ma*
Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, 20 Nanxin Cun, Xiangshan, Beijing 100093, China
Stem lodging-resistance is an important phenotype in crop production. In the present study, the expression of the wheat COMT gene (TaCM) was determined in basal second internodes of lodging-resistant (H4564) and lodging-susceptible (C6001) cultivars at stem elongation, heading, and milky endosperm corresponding to Zadoks stages Z37, Z60, and Z75, respectively. The TaCM protein levels were analysed by protein gel blot and COMT enzyme activity was determined during the same stem developmental stages. TaCM mRNA levels were higher in H4546 from elongation to the milky stages and in C6001 the TaCM mRNA levels decreased markedly at the heading and milky stages. The TaCM protein levels and COMT activity were also higher in H4564 than that in C6001 at the heading and milky stages. These results corresponded to a higher lignin content measured by the Klason method and stem strength and a lower lodging index in H4564 than in C6001 at the heading and milky stages. Therefore, the TaCM mRNA levels, protein levels, and enzyme activity in developing wheat stems were associated with stem strength and lodging index in these two wheat cultivars. Southern analysis in a different population suggested that a TaCM locus was located in the distal region of chromosome 3BL, which has less investigated by QTL for lodging-resistant phenotype.
