First published online July 12, 2005
Development 132, 1501e (2005)
© The Company of Biologists Limited
Sperm and oocyte: a novel relationship buds
Intercellular communication between sperm and oocyte is essential for
successful sexual reproduction. In nematodes, for example, the major sperm
protein (MSP) acts as a hormone that promotes oocyte meiotic maturation. But
how do sperm, which lack the usual protein secretion machinery, release this
cytoskeletal protein? Kosinski and co-workers now reveal that in C.
elegans, MSP is exported from sperm through a novel vesicle-budding
mechanism (see p.
3357). Their results suggest that the localized assembly of MSP
filaments in spermatozoa and spermatids drives the formation of plasma
membrane protrusions on the cell body, which form vesicles with inner and
outer membranes between which MSP is sandwiched. These vesicles then function
as MSP time-release capsules. Because proteins with MSP domains are found in
fungi, plants and animals, this unconventional protein export pathway might
also function in other developmental situations.
Related articles in Development:
- C. elegans sperm bud vesicles to deliver a meiotic maturation signal to distant oocytes
- Mary Kosinski, Kent McDonald, Joel Schwartz, Ikuko Yamamoto, and David Greenstein
Development 2005 132: 3357-3369.
[Abstract]
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