Study finds key to plant growth control mechanism

A Purdue University study has mapped a complex series of pathways that control the shape of plant cells. The findings are an important step toward customizing how plants grow to suit particular agronomic needs and improving the quality of the cotton grown in the United States.

Cotton production is a $25 billion industry in the United States, but the types of cotton farmers can grow here is of lesser quality than premium Egyptian or Pima cottons, which have smaller fiber diameters. Daniel Szymanski, professor in the Department of Botany and Plant Pathology, analyzed how intracellular signaling networks pattern cell walls to generate particular cell shapes and sizes. This knowledge from the Arabidopsis model system can be used to generate cotton fiber cells with smaller diameter or increased strength.

In findings published in the journal Current Biology, Szymanski described how microtubules and actin, protein polymers that form the cytoskeletons of plant cells, are organized to specify the mechanical properties of cell walls that define cell shape.

Szymanski’s group found that microtubules entrap a protein called SPIKE 1 within the apex of a cell where SPIKE 1 recruits additional protein machineries that cause actin filaments to form. Actin filament networks are then organized as roadways for long-distance intracellular transport and the regulated delivery of cell wall materials that are necessary for cell growth.

“SPIKE 1 is a master regulator in cells, a switch that when activated determines the time and location where actin networks are polymerized,” Szymanski said.

The location and activity of SPIKE1 is important. Without it, growth is misregulated, leading to distorted cell shapes that do not taper properly. The SPIKE1 protein is one of a growing number of tools that could be used to program the size and shapes of economically important cells, including cotton fibers.

Szymanski said this new understanding will also likely play a broader role in designing plants that have different cell shapes and sizes.

“Cells are building blocks for tissues and organs, and they have the potential to influence key traits like leaf size,” Szymanski said. “This work provides a knowledge base that will enable cell, tissue and organ engineering.”

A National Science Foundation Molecular and Cellular Biosciences Grant supported this research. 

Daniel Szymanski used the model plant Arabidopsis (in his hand) to map the complex pathways that control plant cell shape. The findings may be key to improving the quality of cotton (in the background) grown in the United States. (Purdue Ag Communication photo/Tom Campbell) Daniel Szymanski used the model plant Arabidopsis (in his hand) to map the complex pathways that control plant cell shape. The findings may be key to improving the quality of cotton (in the background) grown in the United States. (Purdue Ag Communication photo/Tom Campbell)

Featured Stories

Carl Kincaid standing by a trail.
Transforming spaces, enriching lives through landscape architecture

If you’ve strolled along the Indianapolis Cultural Trail, biked the Monon Boulevard in...

Read More
Meghan Hartman by statue with children at the Celery Bogg Nature Center.
From classroom to camp: Purdue student’s AmeriCorps summer service term inspires environmental stewardship

As dawn breaks over the Celery Bog Nature Area, Meghan Hartman, a sophomore in Natural Resources...

Read More
Julie Young
Behind the Research: Julie Young

Weed scientist Julie Young’s workweeks are sometimes chaotic — but never dull. On any...

Read More
Steve Dahnke, Jack Ward and Larry and Janet White
Four inducted into Indiana Livestock Breeders Association Hall of Fame

Steve Dahnke, Jack Ward and Larry and Janet White join the ILBA Hall of Fame.

Read More
yellow agave flower sprout from the giant flower stalk against a clear blue sky
The death bloom of a century plant

Agave americana, also known as the century plant, has evolved for a dry desert life. For 30...

Read More
Two Purdue students compete in the Jack and Jack double buck competition at Midwest Conclave 2026
FNR Students Experience Midwest Forestry Conclave

The Purdue student chapter of the Society of American Foresters participated in the 69th Midwest...

Read More