Cleavage, incomplete inversion, and cytoplasmic bridges in Gonium pectorale (Volvocales, Chlorophyta).
J Plant Res
; 126(5): 699-707, 2013 Sep.
Article
in En
| MEDLINE
| ID: mdl-23455615
ABSTRACT
Multicellularity arose several times in evolution of eukaryotes. The volvocine algae have full range of colonial organization from unicellular to colonies, and thus these algae are well-known models for examining the evolution and mechanisms of multicellularity. Gonium pectorale is a multicellular species of Volvocales and is thought to be one of the first small colonial organisms among the volvocine algae. In these algae, a cytoplasmic bridge is one of the key traits that arose during the evolution of multicellularity. Here, we observed the inversion process and the cytoplasmic bridges in G. pectorale using time-lapse, fluorescence, and electron microscopy. The cytoplasmic bridges were located in the middle region of the cell in 2-, 4-, 8-, and 16-celled stages and in inversion stages. However, there were no cytoplasmic bridges in the mature adult stage. Cytoplasmic bridges and cortical microtubules in G. pectorale suggest that a mechanism of kinesin-microtubule machinery similar to that in other volvocine algae is responsible for inversion in this species.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cell Division
/
Chlorophyta
Language:
En
Journal:
J Plant Res
Journal subject:
BOTANICA
Year:
2013
Type:
Article
Affiliation country:
Japan