3-d-time-lapse-imaging-cell-wall-dynamics-using-calcofluor-moss

3-D Time-Lapse Imaging of Cell Wall Dynamics Using Calcofluor in the Moss <em>Physcomitrium patens</em>

Time-lapse imaging with fluorescence microscopy allows observation of the dynamic changes of growth and development at cellular and subcellular levels. In ...

University of Louisville

Shoot phototropism benefits growth and metabolism in land plants by enabling them to position their photosynthetic organs in favorable light conditions. Nonvascular land plants, like the ancestors of modern mosses, are believed to have been among the first plants to occupy the land. To understand the evolutional history of shoot phototropism in land plants, we have established a system for experimentally studying phototropism in gametophores of the moss Physcomitrella patens. Here we will describe the key points in our system, including obtaining etiolated gametophores, the light sources used for inducing bending, and the methods for evaluation of phototropic responses.

An Experimental System for Examining Phototropic Response of Gametophytic Shoots in the Moss Physcomitrella patens.

A complete picture of how signaling pathways lead to multicellularity is largely unknown. Previously, we generated mutations in a protein prenylation enzyme, GGB, and showed that it is essential for maintaining multicellularity in the moss Physcomitrium patens. Here, we show that ROP GTPases act as downstream factors that are prenylated by GGB and themselves play an important role in the multicellularity of P. patens. We also show that the loss of multicellularity caused by the suppression of GGB or ROP GTPases is due to uncoordinated cell expansion, defects in cell wall integrity and the disturbance of the directional control of cell plate orientation. Expressing prenylatable ROP in the ggb mutant not only rescues multicellularity in protonemata but also results in development of gametophores. Although the prenylation of ROP is important for multicellularity, a higher threshold of active ROP is required for gametophore development. Thus, our results suggest that ROP activation via prenylation by GGB is a key process at both cell and tissue levels, facilitating the developmental transition from one dimension to two dimensions and to three dimensions in P. patens.

Liang Bao

Department of Biology

University of Louisville

3-D Time-Lapse Imaging of Cell Wall Dynamics Using Calcofluor in the Moss Physcomitrium patens

Liang Bao

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Biology

University of Louisville

3-D Time-Lapse Imaging of Cell Wall Dynamics Using Calcofluor in the Moss Physcomitrium patens

Department of Biology