Submitted to: Plant Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/10/2002
Publication Date: 4/1/2002
Citation: Horvath, D.P., Chao, W.S., Anderson, J.V. 2002. Molecular analysis of signals controlling dormancy and growth in underground adventitious buds of leafy spurge. Plant Physiology. 128:1439-1446. Interpretive Summary: This paper presents the identification of genes that respond to signals controlling growth of underground buds of the noxious perennial weed leafy spurge. These genes were then used as markers to follow cell division processes in the underground buds. It was learned that the two signals previously known to control bud growth (sugar and the plant hormone auxin) prevent growth of the buds by blocking cell division at distinct points in the cell cycle. These findings have led to the generation of a model for the control of underground bud growth in leafy spurge that has likely identified key proteins that may serve as potential targets for the development of novel means to control this weed.
Technical Abstract: Dormancy and subsequent regrowth of adventitious buds is a critical physiological process for many perennial plants. We have used the expression of different hormone and cell cycle responsive genes as markers to follow this process in leafy spurge. In conjunction with earlier studies, we show that loss of mature leaves and concomitant decreased sugar levels results in increased GA perception in underground adventitious buds and induction of S-phase-specific but not M-phase- specific gene expression. Loss of both apical and axillary buds did not result in induction of S-phase- or M-phase-specific gene expression. However, loss of these organs was necessary for continuation of the cell cycle and further bud development if S-phase was previously initiated. This information suggests a possible model for control of dormancy in adventitious buds of leafy spurge.