DynaMo postdoc Deyang Xu co-author of Plant Journal cover story

The Plant Journal August 2015 cover story is co-authored by DynaMo member Deyang Xu.

The research image adorning the cover of the latest issue of the Plant Journal shows a two-days-old developing Arabidopsis leaf captured by confocal microscopy.

The image shows the phases of leaf development from the proliferation phase (bottom) to the expansion and differentiation phase (top). The phases coexist showing a tip-to-base gradient, but the molecular mechanism directing this pattern of leaf development is as yet poorly understood.

A signal for cell differentiation

Deyang Xu, postdoctoral researcher at the DynaMo Center since 2012 and one of the authors of the paper, explains:

“The cover picture shows Reactive Oxygen Species (ROS) accumulation patterns in a developing Arabidopsis leaf. Cellular transition from the proliferation pase to the differentiation phase is important for proper development of the leaf and it is known that ROS at high levels are capable of blocking the cell proliferation. In this paper we demonstrate that ferulic acid, the channeled intermediates of lignin biosynthesis, play a role in when cells stop proliferating as it acts as an endogenous antagonist of the ROS.”

At the bottom of the pictures are the newest cells. The red signal comes from auto-fluorescence of the chlorophyll which is present in all cells, but the very youngest. The green and yellow stains are fluorescently colored Reactive Oxygen Species (ROS) which only appear in cells beyond the proliferation phase. At the top of this two-days-old leaf, the cells have ceased to divide and are now expanding and differentiating into mature cells.

The science behind the picture

Xue et.al. CCR1, an enzyme required for lignin biosynthesis in Arabidopsis, mediates cell proliferation exit for leaf development. The Plant Journal, 83:3, p. 375–387, August 2015.

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