ISSN 1021-4437, Russian Journal of Plant Physiology, 2009, Vol. 56, No. 1, pp. 110–117. © Pleiades Publishing, Ltd., 2008.
Published in Russian in Fiziologiya Rastenii, 2009, Vol. 56, No. 1, pp. 123–130.
When the protoplasm of many algae (
(Hudson) C. Agardh,
Okamura ex Segawa,
etc) was extruded out or discharged in seawater, it could
reunite into new protoplasts [1–6]. This interesting phe-
nomenon of the assembly of the disintegrated proto-
plasm into ordered, harmonious whole offers us many
opportunities to study the interaction between the cell
organelles, the development of new cells, the formation
and growth of the cell membrane and cell wall, etc.
Kobayashi and Kanaizuka  reported that dissoci-
ated components (chloroplasts and protoplasmic frac-
tion without chloroplasts) of
bled and formed protoplasts, which developed into
mature plants. These authors described this phenome-
non in detail in 1985 . Kim et al.  studied the
reuniﬁcation of the disintegrated whole cell contents of
The text was submitted by the autors in English.
into new protoplasts. They found that an
active swirling movement of cell organelles was
observed during their aggregation. Nile red staining
showed that there was ﬁrst an active internalization of
lipid membranes by the protoplasmic masses. Then,
after subprotoplast formation, some lipid material was
found on their surface.
Although there were many reports about the reuniﬁ-
cation of the
protoplasm, most attention was
put to the aggregation of all the cell organelles. The
behavior of subcellular parts during aggregation of the
protoplasm is still unclear. Therefore, in our lab, Ye et al.
 separated the protoplasm of
two parts: the protoplasmic liquid (PL) and the puriﬁed
organelles (PO) by centrifugation at
for 5 min at
. They found that the PO could aggregate into
numerous balls and ﬁne strands of different sizes in
artiﬁcial seawater. Some aggregations regenerated after
approximately 24 h, and the others gradually disinte-
grated and died. The authors thought that the aggrega-
Lamouroux protoplasm was pro-
ton-gradient dependent and the substances mediating
Assembly of the Subcellular Parts of
Lamouroux into New Protoplasts
, F. Lü
, and B. Zhou
Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071 China;
fax: 86-532-8288-0645; e-mail: email@example.com
College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin, 300457 China
Department of Food Science, Institute of Agriculture, Liaocheng University, Liaocheng, 252059 China
Graduate School, Chinese Academy of Sciences, Beijing, 100039 China
Received September 18, 2007
— The chloroplasts, mitochondria, and protoplasm devoid of mature chloroplasts (PMC) of
Lamouroux were isolated by low-speed and sucrose density centrifugation. The PMC aggregated in
artiﬁcial seawater, and then protoplasts without mature chloroplasts (PtMCs) were formed. Transmission elec-
tron microscopy and cytochemical studies indicated that there were mitochondria, nuclei, vesicles, and other
small cell organelles in the PtMCs. Scanning electron microscopy showed that there were holes on the surface
of 1-h PtMCs and then fewer holes on the surface of 24-h PtMCs, suggesting that a healing process occurred.
The plasma membrane was formed over the surface of the PtMCs. However, the cell wall was not regenerated,
and the newly formed PtMCs were ruptured and died in 3 days. Light intensity during alga maintenance before
use inﬂuenced signiﬁcantly (one-way ANOVA,
< 0.0001) on the number of PtMCs formed; the highest num-
ber of PtMCs was formed at 20
s). When isolated chloroplasts were transferred into seawater, there
were only two or three chloroplasts aggregated together. However, isolated mitochondria and the mixed six lay-
ers of cell organelles (separated by sucrose density centrifugation) could not aggregate in the artiﬁcial seawater.
This indicates that the conjunction of cell organelles is important for their aggregation.
Key words: Bryopsis hypnoides - assembly - cell membrane - chloroplast - mitochondria - protoplast
: DAPI—4',6-diamidino-2-phenylindole; PMC—
protoplasm without mature chloroplasts; PtMCs—protoplasts
without mature chloroplasts.