MUM, a maternal unknown message, inhibits early establishment of the medio-lateral axis in the embryo of the kelp Saccharina latissima.
Development
; 151(20)2024 Oct 15.
Article
in En
| MEDLINE
| ID: mdl-39190296
ABSTRACT
Brown algae are multicellular photosynthetic organisms that have evolved independently of plants and other algae. Here, we have studied the determinism of body axis formation in the kelp Saccharina latissima. After microdissection of the embryo, we show that the stalk, an empty cell that retains the embryo on the maternal tissue, represses longitudinal cell divisions in the early embryo, thereby reinforcing the establishment of the initial apico-basal axis. In addition, it promotes cell growth and controls cell shape and arrangement in the flat oblong embryo composed of cells aligned in rows and columns. Although the stalk persists for several weeks until the embryo reaches at least 500 cells, proper embryogenesis requires connection to maternal tissue only during the first 4â
days after fertilisation, i.e. before the embryo reaches the 8-cell stage. Transplantation experiments indicate that the maternal signal is not diffused in seawater, but requires contact between the embryo and the maternal tissue. This first global quantitative study of brown algal embryogenesis highlights the role of MUM, an unknown maternal message, in the control of growth axes and tissue patterning in kelp embryos.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Kelp
Language:
En
Journal:
Development
Journal subject:
BIOLOGIA
/
EMBRIOLOGIA
Year:
2024
Document type:
Article
Affiliation country:
France
Country of publication:
United kingdom