In the biological world, there is a fundamental difference in the developmental potential of cells between plants and animals: Plant cells have greater "plasticity". Compared to animal cells, plant cells have greater developmental plasticity. Under certain conditions, they can develop into embryos without fertilization. This difference conceals profound biological principles.

plants: Differentiated cells can 'turn back"

In plants, almost any living cell has the potential to regain totipotency under specific conditions.

One leaf, the whole plant could theoretically be regenerated. A root tip cell that can develop into a complete root system. Even a differentiated sieve tube cell can "start all over again" under the right conditions ".

Plant leaf stomatal precursor cells can "change the fate", from the stomatal development path to the embryonic development path. This process is called "reprogramming of cell fate".

Animals: it is difficult to "turn back" after differentiation"

In stark contrast to plants, the somatic cells of animals, once differentiated, are difficult to reverse.

Mammals is totipotent-it can develop into a complete individual. As development progresses, cells gradually lose totipotency, acquire pluripotency (can only differentiate into cells of a specific lineage), and eventually become fully differentiated terminal cells.

That's what makes cloning so challenging.

Dolly sheep, which was born in 1997, was realized through somatic cell nuclear transfer technology-a differentiated somatic cell is nuclear transferred to an enucleated egg cell, and with the help of the "reprogramming" ability of the egg cell cytoplasm, the nucleus "forgets" its identity and starts development again.

Is "reprogrammed" in animals, it is far less efficient than in plants.

Why are plant cells more "plastic"?

1. Existence of growing points (merimetic tissue)

Plants retain active meristem-shoot apical meristem and root apical meristem-throughout their lives. Cells in these areas remain undifferentiated or weakly differentiated, providing a continuous source of cells for plant growth.

2. "Fixation" of the cell wall

Interestingly, plant cell walls are both a limitation (cells cannot move) and an advantage. Being unable to move, plants have evolved greater cell fate plasticity-individual cells must be able to independently respond to environmental changes and repair damage.

3. Unique hormone system

Phytohormones (especially auxin) play a central role in the regulation of cell fate. It has been found that the accumulation of endogenous auxin is a key switch that triggers the totipotency of plant cells. In animals, the mechanisms that regulate cell fate are completely different.

4. Epigenetic flexibility

Plants is more flexible. In GMC-auxin intermediate state, plant cells can undergo deep chromatin remodeling, and a large number of silent genes are gradually activated. This "genome reprogramming" ability far exceeds that of animal cells.

Scientific revelation

The study of the mechanism of plant cell totipotency not only helps us understand the development law of plant itself, but also provides enlightenment for the study of animal cell reprogramming.

In animal cells, somatic cells can be reprogrammed into pluripotent stem cells using small chemical molecules to regulate epigenetic pathways and signal transduction. This suggests that both pluripotency and totipotency of animal and plant cells are regulated by epigenetics, and how to overcome epigenetic barriers is the key to artificially manipulate cell fate changes.

References:

1. Tang, L., et al. Time-resolved reprogramming of single somatic cells into totipotent states during plant regeneration. Cell, 2025.

2. Review article: From single somatic cell to totipotent embryo: the reprogramming journey of cell fate