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

A landscape view of Pfendler Hall, one of the three buildings that houses faculty and staff from Purdue Forestry and Natural Resources.
FNR Honors Four Individuals for Department Service in 2025

The Purdue Department of Forestry and Natural Resources has honored four individuals for their...

Read More
the Szymanski and Siegmund labs stand together in front of photos and models of leaf epidermis on a screen between them.
Sticking together under stress: NSF grant brings plant biologists and engineers together to discover how tissues stay connected

Daniel Szymanski, professor of Purdue’s Departments of Botany and Plant Pathology and...

Read More
Ag Barometer
Farmer sentiment drifts lower as trade uncertainty hangs over agriculture

Farmer sentiment dipped slightly in December, with the Purdue University/CME Group Ag Economy...

Read More
Photos from the top 2025 stories for Purdue College of AG
What people clicked, watched and read in 2025

Explore the top content from 2025 for the Purdue College of Agriculture.

Read More
Wildlife alumna Lauren Wetterau kneels next to a red squirrel midden in the Greater Yellowstone ecosystem; a red squirrel sits on downed tree
Alumna Lauren Wetterau's Research Featured on Animal Planet Show

2023 wildlife alumna Lauren Wetterau is coming to a television screen or streaming service near...

Read More
Lenny Farlee shows teachers how to use a Biltmore stick at the Natural Resources Teachers Academy.
FNR Extension Set to Offer Four Editions of Forest Management for the Private Woodland Owner Course in Spring 2026

Do you want to learn more about trees, forests and how to better manage your woodlands for a...

Read More