What is the Difference Between Kinetin and Zeatin

The key difference between kinetin and zeatin is that kinetin is a synthetic form of cytokinin hormone, while zeatin is a naturally occurring form of cytokinin hormone.

Cytokinins are a class of plant hormones that promote cell division or cytokinesis in shoots and roots. Cytokinins are involved mainly in cell growth and cell differentiation. In addition, cytokinins also affect apical dominance, axillary bud growth, and leaf senescence. There are two types of cytokinins: adenine type cytokinins (kinetin, zeatin, 6-benzylaminopurine) and phenylurea type cytokinins (diphenylurea and thidiazuron (TDZ). Kinetin and zeatin are two forms of adenine-type cytokinins.

CONTENTS

1. Overview and Key Difference
2. What is Kinetin
3. What is Zeatin
4. Similarities – Kinetin and Zeatin
5. Kinetin vs Zeatin in Tabular Form
6. Summary – Kinetin vs Zeatin

What is Kinetin?

Kinetin is a synthetic form of cytokinin and a plant hormone. It promotes cell division. It was originally isolated by Carols Miller and Skoog as a compound from autoclaved herring fish sperm DNA. As this compound had cell division promoting activity in plants, it was given the name kinetin. However, this cell division-promoting activity was induced when auxin was present in the medium. Kinetin is normally used in plant tissue culture experiments to induce the formation of callus in conjunction with auxin. It is also used to regenerate shoot tissues from callus when there is a lower auxin concentration in the medium.

Kinetin was considered an artificial compound produced from the deoxyadenosine residues in herring DNA. Therefore, it was thought that kinetin does not exist naturally. However, several research studies have shown that they exist in humans and various plants. The mechanism of production of kinetin from DNA is through the production of furfural. Furfural is an oxidation product of deoxyribose sugar in DNA. The quenching of furfural is by adenine bases converting it to N6-furfuryladenine (kinetin). Furthermore, kinetin is also widely used in producing new plants from tissue cultures maintained in laboratories.

What is Zeatin?

Zeatin is a naturally occurring form of cytokinin hormone derived from adenine. It normally occurs in the form of a cis and a trans isomer. It can also occur as a conjugate. Zeatin was discovered in immature corn kernels from the genus Zea. Zeatin is used to promote the growth of lateral buds. Moreover, when zeatin is sprayed on meristems, it stimulates cell division to produce bushier plants. Zeatin is naturally occurring in many plant extracts and is also present in coconut milk as an active ingredient. 6-(γ,γ-Dimethylallylamino)purine is a precursor of zeatin.

Zeatin has several anti-aging effects on human skin fibroblasts. Furthermore, the other application of zeatin includes promoting callus initiation when combined with auxin, promoting fruit set, retarding yellowing of vegetable, causing auxiliary stems to grow and flower, stimulating seed germination, seeding growth, and promoting the resistance of tobacco against the bacterial pathogen Pseudomonas syringae.

What are the Similarities Between Kinetin and Zeatin?

• Kinetin and zeatin are two types of adenine type cytokinins.
• Both forms are derived from DNA.
• Both forms induce callus growth in the presence of auxin.
• They have various important applications.

What is the Difference Between Kinetin and Zeatin?

Kinetin is a synthetic form of cytokinin hormone, while zeatin is a naturally occurring form of cytokinin hormone. Thus, this is the key difference between kinetin and zeatin. Furthermore, the precursor for kinetin is furfural whereas the precursor for zeatin is 6-(γ,γ-Dimethylallylamino)purine.

The below infographic presents the differences between kinetin and zeatin in tabular form for side-by-side comparison.

Summary – Kinetin vs Zeatin

Cytokinins are plant-specific chemical messengers or hormones that play a central role in the regulation of the plant cell cycle and numerous developmental processes. Kinetin and zeatin are two adenine-type cytokinins. Kinetin is a synthetic form of cytokinin hormone, while zeatin is a naturally occurring form of cytokinin hormone. So, this summarizes the difference between kinetin and zeatin.

Reference:

1. “Kinetin – An Overview.” ScienceDirect Topics.
2. “Zeatin.” ACS | American Chemical Society.

Image Courtesy:

1. “Kinetine” By Fjeojf – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “Зеатин” By Зеатин – Own work (CC BY-SA 4.0) via Commons Wikimedia