A scientific conjecture that has existed for more than 120 years.

1902, the German botanist Haberlandt put forward a far-reaching conjecture: every living cell of a plant carries all the genetic information to develop into a complete plant. This means that a leaf, a stem, or even a single cell can "turn" into a complete plant under suitable conditions.

This is the origin of the concept of "plant cell totipotency.

For more than 120 years, scientists have been asking: how on earth does an already differentiated "ordinary cell" "forget" its original identity, regain the ability to resemble a fertilized egg, and finally develop into a complete plant?

The answer to this question has been pending. In 2005, on the occasion of its 125 anniversary, the top international journal Science (Science) listed "how a single somatic cell develops into a complete plant" as one of the 125 most challenging cutting-edge scientific issues in the world.

Until September 16, 2025, the answer is finally revealed.

What is the plant cell totipotency?

Before going deeper, let's understand this concept.

Plant cell totipotency (Plant Cell Totipotency) refers to the ability of plant cells to reverse differentiation to form totipotent stem cells similar to fertilized eggs, and then develop into complete plants. This ability is a significant difference between plants and animals. Once animal cells differentiate, it is difficult to "turn back". But plant cells are different:

You casually insert a branch of green dill, it can grow into a basin of new green dill;

A fleshy leaf that falls on the soil can take root and sprout;

Cut a piece of sweet potato root, also can grow vines;

These common phenomena in daily life, behind the cell totipotency in play.

Study of this phenomenon, explained: "Compared with animal cells, plant cells have stronger developmental plasticity. Under certain conditions, they can develop into embryos without fertilization, a phenomenon called 'somatic embryogenesis '."

Cell "restart" the life program?

In order to answer this question, the team of Zhang Xiansheng and Su Yinghua of Shandong Agricultural University has carried out 20 years of research on the model plant Arabidopsis thaliana since 2005. The core challenge of the research is: how to establish a stable experimental system, so that a single plant cell "obediently" from ordinary cells into embryos?

2009, the team first found in Arabidopsis that the accumulation of large amounts of auxin is the "switch" that activates the cell's totipotency ". But the system was not perfect at the time, and the cells still needed to form callus (similar to "scar tissue") before they could further become embryos, a process that was complex and difficult to track.

The real turning point came in 2011.

Tang Liping, a master's student of Professor Su Yinghua, discovered that an inducing factor can directly grow embryonic structures on the leaf surface of seedlings-these embryos actually originate from a single cell on the leaf surface.

"This system is perfect! Leaf cells do not form callus, direct 'bulge' into embryos, clean and clear." Su Yinghua immediately realized that the "key" to solve the problem had been found.

Captures for the first time the whole process of "a cell into a plant"

With a stable induction system, the team still needs a way to "see" the process. They found a fluorescent marker that glows only in totipotent stem cells. With this mark, you can use a laser confocal microscope to track the "transformation" of a cell for three or four days.

This is the first time that humans have captured the entire process of cell division in a single plant:

[1 cell & rarr; divided into 2 & rarr; with the special pattern of "3 in a group" & rarr; gradually forming an embryo of 12 cells]]

These pictures and videos, each frame is unique evidence in the world, visually confirming the "single cell" of plant cells ".

Professor Su Yinghua said excitedly: "Every picture and every video is unique evidence in the world."

Two keys, open the same lock

So, what makes this cell "change its mind?

Team found the "key key" to trigger cell totipotency: the gene SPCH, which is unique to leaf stomatal precursor cells, and the gene LEC2, which is highly expressed by artificial induction. The two work together to form a "molecular switch".

"It's like turning a lock requires two keys, one is indispensable." Professor Zhang Xiansheng uses this metaphor to explain.

Was originally destined to develop into stomata "precursor cells", under the synergistic effect of LEC2 and SPCH, activated the auxin synthesis pathway, resulting in the accumulation of auxin in the cell. This makes the precursor cells out of the "stomatal development road" and become the pluripotent stem cells that can give birth to new life.

Researchers named this key transition state "GMC-auxin intermediate state".

Why is this important?

The implications of this discovery go far beyond solving a century-old puzzle.

Professor Zhang Xiansheng pointed out that the analysis of this theory not only helps to understand the fundamental laws of plant cell development, but also provides new ideas and technical tools for precise regulation of plant regeneration and directional improvement of crop traits.

Traditional cross breeding usually takes 8 to 10 years. In the future, it may be possible to achieve "rapid cloning" of fine crop varieties through precise regulation of cell totipotency, and greatly shorten the breeding cycle.

At present, the system has been verified in wheat, corn and soybean and other major crops. Zhong Kang, an academician of the Chinese Academy of Sciences, commented that the discovery opened up a new path to break the long-standing "regeneration bottleneck" of agricultural biotechnology.

Five strategic significance

1. Breaking the "regeneration bottleneck" of agriculture"

Zhong Kang, an academician of the Chinese Academy of Sciences, pointed out that the discovery "opens up a new path to break the long-standing 'regeneration bottleneck' of agricultural biotechnology". For a long time, many important crops are difficult to regenerate efficiently in the laboratory, which restricts the application of genetic engineering and molecular breeding. Now, this bottleneck has the possibility of a breakthrough.

2. Accelerating Precision Design Breeding

Traditional breeding cycle is long and the efficiency is low. The mechanism revealed by this study provides a theoretical basis for the "rapid cloning" of fine varieties. In the future, breeders can efficiently fix heterosis in the laboratory, shortening the breeding cycle from 8-10 years to 2-3 years.

3. Protection of plant germplasm resources

For rare and endangered plants, this technology provides a new way of protecting them: instead of saving seeds or living plants, you only need to save cells to regenerate whole plants when needed.

4. Energizing Synthetic Biology

Plants as "bioreactors" to produce high-value compounds is an important direction of synthetic biology. Efficient plant regeneration system is the key to the success of this technical route.

5. Serving National Food Security

The technology is applied to wheat, corn, soybeans and other major food crops, it will provide new technical support for ensuring national food security.

References:

- Tang, L., et al. Time-resolved reprogramming of single somatic cells into totipotent states during plant regeneration. Cell, 2025. DOI: 10.1016/j.cell. 2025.08.031

- Science 125th Anniversary Issue: 125 Questions, 2005.

-Cell: Published online September 16, 2025

-"Science" (Science) magazine: 2005 "how a single somatic cell develops into a complete plant" as one of the 125 cutting-edge scientific issues

-China Science News: reported on September 17, 2025

-Guangming Daily: reported on September 18, 2025