Abstract:
:We investigated the manner in which the sea urchin larva takes up calcium from its body cavity into the primary mesenchymal cells (PMCs) that are responsible for spicule formation. We used the membrane-impermeable fluorescent dye calcein and alexa-dextran, with or without a calcium channel inhibitor, and imaged the larvae in vivo with selective-plane illumination microscopy. Both fluorescent molecules are taken up from the body cavity into the PMCs and ectoderm cells, where the two labels are predominantly colocalized in particles, whereas the calcium-binding calcein label is mainly excluded from the endoderm and is concentrated in the spicules. The presence of vesicles and vacuoles inside the PMCs that have openings through the plasma membrane directly to the body cavity was documented using high-resolution cryo-focused ion beam-SEM serial imaging. Some of the vesicles and vacuoles are interconnected to form large networks. We suggest that these vacuolar networks are involved in direct sea water uptake. We conclude that the calcium pathway from the body cavity into cells involves nonspecific endocytosis of sea water with its calcium.
journal_name
Proc Natl Acad Sci U S Aauthors
Vidavsky N,Addadi S,Schertel A,Ben-Ezra D,Shpigel M,Addadi L,Weiner Sdoi
10.1073/pnas.1612017113subject
Has Abstractpub_date
2016-11-08 00:00:00pages
12637-12642issue
45eissn
0027-8424issn
1091-6490pii
1612017113journal_volume
113pub_type
杂志文章abstract::The development of Drosophila organ discs can be arrested by culturing them in adult male flies. These aged discs lose some of their differentiation competence and form incomplete imaginal structures. The more advanced the aging, the greater the loss of competence. Discs made to differentiate prematurely show deficien...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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