植物的葉子即可以是一個簡單的葉片,，也可以由多個單獨的小葉組成。此外，無論單葉還是復(fù)葉都可能具有齒狀或圓突狀的邊緣,。法國國家農(nóng)業(yè)研究所和牛津大學(xué)的科學(xué)家找到了負(fù)責(zé)雙子葉植物葉片形成的基因家族,。
研究人員重點研究了NAM/CUC3基因家族，當(dāng)葉子從莖上生長時,，這類基因使葉子的邊界區(qū)域出現(xiàn)分離,。科學(xué)家們研究了這些基因在耬斗菜,、西紅柿,、碎米芥和豌豆等具有小葉的一類遠(yuǎn)親植物中的表達(dá)情況。他們發(fā)現(xiàn),，這些基因在嫩葉周圍的邊界區(qū)域中表達(dá),，并且這種表達(dá)要先于葉子出現(xiàn)。利用具有NAM/CUC3缺陷表達(dá)的突變體,，研究人員證明了這類基因家族的重要性,。沒有這些基因，葉子生長就會出現(xiàn)反常,，鋸齒狀邊緣消失,，小葉長在一起，并且葉子數(shù)目減少,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science 19 December 2008:DOI: 10.1126/science.1166168
A Conserved Molecular Framework for Compound Leaf Development
Thomas Blein,1 Amada Pulido,1 Aurélie Vialette-Guiraud,1* Krisztina Nikovics,1 Halima Morin,1,2 Angela Hay,3 Ida Elisabeth Johansen,4 Miltos Tsiantis,3 Patrick Laufs1
Diversity in leaf shape is produced by alterations of the margin: for example, deep dissection leads to leaflet formation and less-pronounced incision results in serrations or lobes. By combining gene silencing and mutant analyses in four distantly related eudicot species, we show that reducing the function of NAM/CUC boundary genes (NO APICAL MERISTEM and CUP-SHAPED COTYLEDON) leads to a suppression of all marginal outgrowths and to fewer and fused leaflets. We propose that NAM/CUC genes promote formation of a boundary domain that delimits leaflets. This domain has a dual role promoting leaflet separation locally and leaflet formation at distance. In this manner, boundaries of compound leaves resemble boundaries functioning during animal development.
1 Laboratoire de Biologie Cellulaire, Institut Jean Pierre Bourgin, Institut National de la Recherche Agronomique (INRA), 78026 Versailles Cedex, France.
2 Plateforme de Cytologie et d'Imagerie Végétale, Institut Jean Pierre Bourgin, INRA, 78026 Versailles Cedex, France.
3 Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK.
4 Department of Genetics and Biotechnology, University of Aarhus, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
