Tip growth
Encyclopedia
Tip growth is an extreme form of polarised growth of living cells that results in an elongated cylindrical cell morphology with a rounded tip at which the growth activity takes place. Tip growth occurs in algae (e.g., Acetabularia acetabulum
), fungi (hypha
e) and plants (e.g. root hairs
and pollen tubes).
Tip growth is a process that has many similarities in diverse walled cells such as pollen tubes, root hairs, and hyphae. However, due to the diversity of the experimental systems, it is unusual for those working on the phenomenon to have the opportunity to get together and compare systems and concepts. From June 19 to 23, 2000, NATO, the European Commission and the Università di Siena sponsored a NATO Advanced Research Workshop which brought together 75 of the current tip growth investigators for a focused exchange of information and ideas on this fascinating topic.
Fungal tip growth and hyphal tropismshttp://www.biology.ed.ac.uk/research/groups/jdeacon/microbes/apical.htm
Fungal hyphae extend continuously at their extreme tips, where enzymes are released into the environment and where new wall materials are synthesised. The rate of tip extension can be extremely rapid - up to 40 micrometres per minute. It is supported by the continuous movement of materials into the tip from older regions of the hyphae. So, in effect, a fungal hypha is a continuously moving mass of protoplasm in a continuously extending tube.
This unique mode of growth - apical growth - is the hallmark of fungi, and it accounts for much of their environmental and economic significance
Acetabularia
Acetabularia is a genus of green algae, specifically of the Polyphysaceae family, Typically found in subtropical waters, Acetabularia is a single-celled organism, but gigantic in size and complex in form, making it an excellent model organism for studying cell biology...
), fungi (hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e) and plants (e.g. root hairs
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...
and pollen tubes).
Tip growth is a process that has many similarities in diverse walled cells such as pollen tubes, root hairs, and hyphae. However, due to the diversity of the experimental systems, it is unusual for those working on the phenomenon to have the opportunity to get together and compare systems and concepts. From June 19 to 23, 2000, NATO, the European Commission and the Università di Siena sponsored a NATO Advanced Research Workshop which brought together 75 of the current tip growth investigators for a focused exchange of information and ideas on this fascinating topic.
Fungal tip growth and hyphal tropismshttp://www.biology.ed.ac.uk/research/groups/jdeacon/microbes/apical.htm
Fungal hyphae extend continuously at their extreme tips, where enzymes are released into the environment and where new wall materials are synthesised. The rate of tip extension can be extremely rapid - up to 40 micrometres per minute. It is supported by the continuous movement of materials into the tip from older regions of the hyphae. So, in effect, a fungal hypha is a continuously moving mass of protoplasm in a continuously extending tube.
This unique mode of growth - apical growth - is the hallmark of fungi, and it accounts for much of their environmental and economic significance