美國冷泉港實驗室的David Jackson及其同事鑒定出一個在控制玉米植株發(fā)育中發(fā)揮關(guān)鍵作用的基因,。研究人員發(fā)現(xiàn)，名為spi1的基因（稀疏花序）參與了玉米植物生長素的合成,。眾所周知,，生長素可以控制植物器官發(fā)育和頂端優(yōu)勢,。
科學(xué)家們發(fā)現(xiàn),，spi1的表達沉默會導(dǎo)致植物器官發(fā)育遲緩,、有缺陷。植物器官初期被稱為分生組織,，是一種類似于動物體內(nèi)干細胞的未分化細胞,。據(jù)了解，分生組織產(chǎn)生于各種細胞合成生長素的相互作用以及它們之間的活動,。
“我們的研究表明,，玉米中的spi1在生長素合成中起主導(dǎo)作用，在植物科學(xué)家所稱的花序發(fā)育中也至關(guān)重要--種子植物借助這一過程中的發(fā)芽來支持植物的開花,，” Jackson說,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS September 17, 2008, doi: 10.1073/pnas.0805596105
sparse inflorescence1 encodes a monocot-specific YUCCA-like gene required for vegetative and reproductive development in maize
Andrea Gallavotti*,?,?, Solmaz Barazesh?,§, Simon Malcomber?, Darren Hall*, David Jackson?, Robert J. Schmidt*, and Paula McSteen
The plant growth hormone auxin plays a critical role in the initiation of lateral organs and meristems. Here, we identify and characterize a mutant, sparse inflorescence1 (spi1), which has defects in the initiation of axillary meristems and lateral organs during vegetative and inflorescence development in maize. Positional cloning shows that spi1 encodes a flavin monooxygenase similar to theYUCCA (YUC) genes of Arabidopsis, which are involved in local auxin biosynthesis in various plant tissues. In Arabidopsis, loss of function of single members of theYUC family has no obvious effect, but in maize the mutation of a single yuc locus causes severe developmental defects. Phylogenetic analysis of the different members of the YUC family in moss, monocot, and eudicot species shows that there have been independent expansions of the family in monocots and eudicots.spi1 belongs to a monocot-specific clade, within which the role of individual YUCgenes has diversified. These observations, together with expression and functional data, suggest that spi1 has evolved a dominant role in auxin biosynthesis that is essential for normal maize inflorescence development. Analysis of the interaction between spi1 and genes regulating auxin transport indicate that auxin transport and biosynthesis function synergistically to regulate the formation of axillary meristems and lateral organs in maize.
