Partial Purification and Characterization of a Glycoprotein Cell Fusion Hormone from Griffithsia pacifica, a Red Alga.

In filaments of the red alga Griffithsia, dead intercalary cells are replaced by the process of cell repair by cell fusion. This process is coordinated by a morphogenetic cell fusion hormone, rhodomorphin, which accelerates cell division and induces the production of a specialized repair cell. We have isolated rhodomorphin from Griffithsia pacifica Kylin and have purified it by concanavalin A affinity chromatography, hydrophobic interaction chromatography, and gel filtration chromatography.

Isolation of a cell-fusion hormone from Griffithsia pacifica kylin, a red alga.

Filaments of Griffithsia pacifica replace dead cells by the process of cell repair. When an intercalary cell is killed, but its cell wall remains intact holding the two halves of the plant together, the cell above it produces a repair rhizoid cell; the cell below it produces a specialized, rhizoid-like repair shoot cell. The repair rhizoid and shoot grow towards each other, meet, and fuse to form a single shoot cell.

Parasexually produced hybrids between female and male plants of Griffithsia tenuis C. Agardh, a red alga.

Somatic cell fusion between vegetative cells of a male and a female isolate of Griffithsia tenuis, a marine red alga, has been obtained. Hybrid cells have been isolated and they have regenerated new plants. Almost all these hybrid plants made reproductive structures.

Analysis of cell elongation in red algae by fluorescent labelling.

The mechanism of cell elongation in five red algae, Griffithsia pacifica Kylin, G. tenuis C. Agardh, G.