Conidial anastomosis tubes
Encyclopedia
Conidial anastomosis tubes (CATs) are cells formed from the conidia (a type of fungal asexual spores) of many filamentous fungi. These cells have a tubular shape and form an anastomosis
(bridge) that allows fusion between conidia.
CATs and germ tube
s (germination tubes) are some of the specialized hypha
e (long cells formed by filamentous fungal species) that are formed by fungal conidia. CATs are morphologically
and physiologically distinct from germ tubes and are under separate genetic control.
Germ tubes, produced during conidial germination, are different from CATs because: CATs are thinner, shorter, lack branches, exhibit determinate growth, and home toward each other.
CAT biology is not completely understood. Initially, conidia are induced to form CATs. Once they are formed, they grow homing toward each other, and eventually they fuse. Once fusion occurs, the respective nuclei can pass through the fused CATs from one conidium to the other. These are events of fungal vegetative growth (asexual reproduction
) and not sexual reproduction
. Part of the CAT fusion (cell fusion
) have been show to be a coordinated behaviour.
The filamentous fungus Neurospora crassa
(bread mould) produces CATs from conidia and conidial germ tubes. In contrast, the fungal plant pathogen, Colletotrichum lindemuthianum
, only produces CATs from conidia and not from germ tubes.
Fusion between these cells seems to be important for some fungi during early stages of colony establishment. The production of these cells has been suggested to occur in 73 different species of fungi.
Anastomosis
An anastomosis is the reconnection of two streams that previously branched out, such as blood vessels or leaf veins. The term is used in medicine, biology, mycology and geology....
(bridge) that allows fusion between conidia.
CATs and germ tube
Germ tube
A germ tube is an outgrowth produced by spores of spore-releasing fungi during germination.The germ tube differentiates, grows, and develops by mitosis to create somatic hyphae....
s (germination tubes) are some of the specialized 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 (long cells formed by filamentous fungal species) that are formed by fungal conidia. CATs are morphologically
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
and physiologically distinct from germ tubes and are under separate genetic control.
Germ tubes, produced during conidial germination, are different from CATs because: CATs are thinner, shorter, lack branches, exhibit determinate growth, and home toward each other.
CAT biology is not completely understood. Initially, conidia are induced to form CATs. Once they are formed, they grow homing toward each other, and eventually they fuse. Once fusion occurs, the respective nuclei can pass through the fused CATs from one conidium to the other. These are events of fungal vegetative growth (asexual reproduction
Asexual reproduction
Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...
) and not sexual reproduction
Sexual reproduction
Sexual reproduction is the creation of a new organism by combining the genetic material of two organisms. There are two main processes during sexual reproduction; they are: meiosis, involving the halving of the number of chromosomes; and fertilization, involving the fusion of two gametes and the...
. Part of the CAT fusion (cell fusion
Cell fusion
Cell fusion is an important cellular process that occurs during differentiation of muscle, bone and trophoblast cells, during embryogenesis, and during morphogenesis...
) have been show to be a coordinated behaviour.
The filamentous fungus Neurospora crassa
Neurospora crassa
Neurospora crassa is a type of red bread mold of the phylum Ascomycota. The genus name, meaning "nerve spore" refers to the characteristic striations on the spores. The first published account of this fungus was from an infestation of French bakeries in 1843. N...
(bread mould) produces CATs from conidia and conidial germ tubes. In contrast, the fungal plant pathogen, Colletotrichum lindemuthianum
Colletotrichum lindemuthianum
Colletotrichum lindemuthianum is a plant pathogen, which causes anthracnose of common bean .-Conidial anastomosis tubes:...
, only produces CATs from conidia and not from germ tubes.
Fusion between these cells seems to be important for some fungi during early stages of colony establishment. The production of these cells has been suggested to occur in 73 different species of fungi.