''Coleochaete'' is a genus of

parenchyma Parenchyma () is the bulk of functional substance in an animal organ or structure such as a tumour. In zoology it is the name for the tissue that fills the interior of flatworms. Etymology The term ''parenchyma'' is New Latin from the word π ...

tous

charophyte Charophyta () is a group of freshwater green algae, called charophytes (), sometimes treated as a division, yet also as a superdivision or an unranked clade. The terrestrial plants, the Embryophyta emerged within Charophyta, possibly from terr ...

green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ( Embryophytes) have emerged deep in the Charophyte alg ...

in the order

Coleochaetales Coleochaetaceae is a family of algae. It is the only family in the Coleochaetales, an order of parenchymous charophyte algae, that includes some of the closest multicellular relatives of land plants. They questionably include the fossil genus ...

. They are haploid, reproduce both sexually and asexually, and have true multicellular organisation, with

plasmodesmata Plasmodesmata (singular: plasmodesma) are microscopic channels which traverse the cell walls of plant cells and some algal cells, enabling transport and communication between them. Plasmodesmata evolved independently in several lineages, and spe ...

communicating between adjacent cells. The plants form flat, sprawling discs on solid surfaces in freshwater streams worldwide, usually as

epiphytes An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

on aquatic plants or growing on the surface of stones. They are seen as one of two most probable sister groups to land plant species, the second candidate group being the

Characeae Characeae is a family of freshwater green algae in the order Charales, commonly known as stoneworts. They are also known as brittleworts or skunkweed, from the fragility of their lime-encrusted stems, and from the foul odor these produce when step ...

. The issue is still not resolved. As they show some of the earliest and simplest features of multicellular plant growth, they are ideal model organisms in the field of

synthetic biology Synthetic biology (SynBio) is a multidisciplinary area of research that seeks to create new biological parts, devices, and systems, or to redesign systems that are already found in nature. It is a branch of science that encompasses a broad ran ...

. They are easy to culture and techniques that have been used to study ''

Arabidopsis thaliana ''Arabidopsis thaliana'', the thale cress, mouse-ear cress or arabidopsis, is a small flowering plant native to Eurasia and Africa. ''A. thaliana'' is considered a weed; it is found along the shoulders of roads and in disturbed land. A winter ...

'' are now being applied to ''Coleochaete''. Experimental systems for plant morphogenesis ''Coleochaete'' has a sterile jacket of cells that surround the gametangia and

zygote A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. In multicell ...

s that are protected by a layer of sterile cells after fertilization. However, unlike land plants, ''Coleochaete'' has zygotic meiosis, meiosis taking place directly in the zygote and not in diploid cells resulting from mitotic division of the zygote.

Species

* '' Coleochaete divergens'' () * '' Coleochaete irregularis'' () * '' Coleochaete nitellarum'' () * '' Coleochaete orbicularis'' () * '' Coleochaete pulvinata'' () * '' Coleochaete sampsonii'' () * '' Coleochaete scutata'' () * '' Coleochaete soluta'' ()

References

External links

* Charophyta Charophyta genera {{green algae-stub