Radioiodination and characterization of the plasma membrane of sea urchin sperm

Sea urchins have long been a model system for the study of fertilization. Much has been learned about how sea urchin sperm locate and fertilize the egg. Sperm and eggs are spawned simultaneously into the surrounding seawater. Sperm signaling pathways lead to downstream events that ensure fertilization. Upon spawning, sperm must acquire motility and then they must swim towards or respond to the egg in some way. Finally, they must undergo a terminal exocytotic event known as the acrosome reaction that allows the sperm to bind to the vitelline layer of the egg and then to fuse with the egg plasma membrane. Motility is stimulated by exposure to seawater, while later events are orchestrated by factors from the egg. The sperm signaling pathways are exquisitely tuned to bring the sperm to the egg, bind, and fuse the two cells as quickly as possible.

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Preparation and characterization of histone H1 from the sperm of the sea-urchin Sphaerechinus granularis

Biochemical Journal ◽

10.1042/bj1950171 ◽

1981 ◽

Vol 195 (1) ◽

pp. 171-176 ◽

Cited By ~ 17

Author(s):

V Giancotti ◽

S Cosimi ◽

P D Cary ◽

C Crane-Robinson ◽

G Geraci

Keyword(s):

Secondary Structure ◽

Sea Urchin ◽

Fluorescence Spectra ◽

Tertiary Structure ◽

Histone H1 ◽

Separation And Purification ◽

Tertiary Structures ◽

Calf Thymus ◽

Sea Urchin Sperm

The separation and purification of histone H1 from the sperm of the sea-urchin Sphaerechinus granularis is described. Physical studies were used to compare this histone H1 molecule with H1 histones from other species. C.d. and 270 MHz n.m.r. spectroscopy indicate that, despite significant compositional differences from other sea-urchin sperm H1 histones, their secondary and tertiary structures are very similar. A large difference in helicity was, however, found between S. granularis histone H1 and calf thymus histone H1, and their n.m.r. and fluorescence spectra also differ considerably. It is concluded that secondary structure and tertiary structure have not been conserved in the evolution of the H1 histone family.

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A cAMP Regulated K+-Selective Channel from the Sea Urchin Sperm Plasma Membrane

Developmental Biology ◽

10.1006/dbio.1996.0072 ◽

1996 ◽

Vol 174 (2) ◽

pp. 271-280 ◽

Cited By ~ 39

Author(s):

Pedro Labarca ◽

Celia Santi ◽

Otilia Zapata ◽

Ezequiel Morales ◽

Carmen Beltrán ◽

...

Keyword(s):

Plasma Membrane ◽

Sea Urchin ◽

Sperm Plasma Membrane ◽

Selective Channel ◽

Sea Urchin Sperm

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C/A dynein isolated from sea urchin sperm flagellar axonemes. Enzymatic properties and interaction with microtubules

Journal of Cell Science ◽

10.1242/jcs.107.2.353 ◽

1994 ◽

Vol 107 (2) ◽

pp. 353-361 ◽

Cited By ~ 1

Author(s):

E. Yokota ◽

I. Mabuchi

Keyword(s):

Atpase Activity ◽

Sea Urchin ◽

Maximal Inhibition ◽

Heavy Chains ◽

Lower Molecular Mass ◽

Cross Bridges ◽

Polypeptide Chains ◽

Brain Tubulin ◽

Sea Urchin Sperm

C/A dynein is a novel dynein isolated from sea urchin sperm flagellar axonemes. It is composed of C and A heavy chains and some additional lower molecular mass polypeptide chains. The characterization of ATPase activity and the interaction of this dynein with microtubules polymerized from calf brain tubulin were investigated in this study. The ATPase activity of C/A dynein (0.3-0.4 mumol Pi/min per mg) was about one half that of outer arm 21 S dynein (0.6-0.8 mumol Pi/min per mg) at 25 degrees C. Vanadate inhibited the ATPase activity with a half-maximal inhibition at 1 microM. C/A dynein absorbed to the glass surface was able to translocate the microtubules towards its plus end. The velocity of the microtubule movement in the presence of 1 mM ATP was 4.0 to 4.5 microns/s at 22 degrees C. C/A dynein binds to and bundles the microtubules even in the presence of ATP. Cross-bridges were found between adjacent microtubules in the bundle with an axial periodicity of about 24 nm. The ATPase activity of C/A dynein was enhanced up to several-fold by the microtubules at concentration as low as 1 mg/ml. On the other hand, 21 S dynein bound to the microtubules with 24 nm axial periodicity only in the absence of ATP. Its ATPase activity was not activated by the microtubules. From these results, it is concluded that the manner of interaction with microtubules of C/A dynein is different from that of the outer arm dynein.

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Ionic Channels in Sea Urchin Sperm Physiology

Physiology ◽

10.1152/physiologyonline.1988.3.5.181 ◽

1988 ◽

Vol 3 (5) ◽

pp. 181-185

Author(s):

A Darszon ◽

A Guerrero ◽

A Lievano ◽

M Gonzalez-Martinez ◽

E Morales

Keyword(s):

Plasma Membrane ◽

Sea Urchin ◽

Acrosome Reaction ◽

Ionic Channels ◽

Good Evidence ◽

Ionic Fluxes ◽

Sea Urchin Sperm

In sea urchin sperm, ionic fluxes modulate the activation of respiration and motility and the acrosome reaction, a prerequisite for egg fertilization. Ionic channels are present in the plasma membrane of these cells, and there is good evidence indicating that they are deeply involved in these processes.

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