The role of the SEA (sea urchin sperm protein, enterokinase and agrin) module in cleavage of membrane-tethered mucins

A nonhydrolyzable ATP analog, adenylyl imidodiphosphate (AMP-PNP), has been used to study the role of ATP binding in flagellar motility. Sea urchin sperm of Lytechinus pictus were demembranated, reactivated, and locked in "rigor waves" by a modification of the method of Gibbons and Gibbons (11). Rigor wave sperm relaxed within 2 min after addition of 4 micrometer ATP, and reactivated upon addition of 10-12 micrometer ATP. The beat frequency of the reactivated sperm varied with ATP concentration according to Michaelis-Menten kinetics ("Km" = 0.24 mM; "Vmax" = 44 Hz) and was competitively inhibited by AMP-PNP (Ki" approximately to 8.1 mM). Rigor wave sperm were completely relaxed (straightened) within 2 min by AMP-PNP at concentrations of 2-4 mM. The possibilities that relaxation in AMP-PNP was a result of ATP contamination, AMP-PNP hydrolysis, or lowering of the free Mg++ concentration were conclusively ruled out. The results suggest that dynein cross-bridge release is dependent upon ATP binding but not hydrolysis.

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Characterization of a Gene Family Encoding SEA (Sea-urchin Sperm Protein, Enterokinase and Agrin)-Domain Proteins with Lectin-Like and Heme-Binding Properties from Schistosoma japonicum

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0002644 ◽

2014 ◽

Vol 8 (1) ◽

pp. e2644

Author(s):

Evaristus Chibunna Mbanefo ◽

Mihoko Kikuchi ◽

Nguyen Tien Huy ◽

Mohammed Nasir Shuaibu ◽

Mahamoud Sama Cherif ◽

...

Keyword(s):

Gene Family ◽

Schistosoma Japonicum ◽

Sea Urchin ◽

Heme Binding ◽

Binding Properties ◽

Sperm Protein ◽

Sea Urchin Sperm

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The role of β-N-acetilglucosaminidase in sea urchin sperm-egg interaction

Cell Differentiation ◽

10.1016/0045-6039(85)90233-7 ◽

1985 ◽

Vol 16 ◽

pp. 100

Keyword(s):

Sea Urchin ◽

Sea Urchin Sperm

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The role of histone H2B from sea urchin sperm in the association of reconstituted minichromosomes

Molecular Biology Reports ◽

10.1007/bf00778507 ◽

1982 ◽

Vol 8 (2) ◽

pp. 71-75 ◽

Cited By ~ 3

Author(s):

T. N. Osipova ◽

V. I. Vorob'ev ◽

M. Böttger ◽

C. -U. von Mickwitz ◽

S. Scherneck

Keyword(s):

Sea Urchin ◽

Histone H2b ◽

Sea Urchin Sperm

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Real-time analysis of the role of Ca2+ in flagellar movement and motility in single sea urchin sperm

The Journal of Cell Biology ◽

10.1083/jcb.200411001 ◽

2005 ◽

Vol 169 (5) ◽

pp. 725-731 ◽

Cited By ~ 95

Author(s):

Christopher D. Wood ◽

Takuya Nishigaki ◽

Toshiaki Furuta ◽

Shoji A. Baba ◽

Alberto Darszon

Keyword(s):

Sea Urchin ◽

Cyclic Gmp ◽

Mammalian Species ◽

Time Analysis ◽

Bending Properties ◽

Alternative Pathways ◽

Real Time Analysis ◽

Directed Motility ◽

Sea Urchin Sperm

Eggs of many marine and mammalian species attract sperm by releasing chemoattractants that modify the bending properties of flagella to redirect sperm paths toward the egg. This process, called chemotaxis, is dependent on extracellular Ca2+. We used stroboscopic fluorescence imaging to measure intracellular Ca2+ concentration ([Ca2+]i) in the flagella of swimming sea urchin sperm. Uncaging of cyclic GMP induced Ca2+ entry via at least two distinct pathways, and we identified a nimodipine-sensitive pathway, compartmentalized in the flagella, as a key regulator of flagellar bending and directed motility changes. We found that, contrary to current models, the degree of flagellar bending does not vary in proportion to the overall [Ca2+]i. Instead we propose a new model whereby flagella bending is increased by Ca2+ flux through the nimodipine-sensitive pathway, and is unaffected by [Ca2+]i increases through alternative pathways.

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A quantitative description of flagellar movement in golden hamster spermatozoa

Journal of Experimental Biology ◽

10.1242/jeb.114.1.463 ◽

1985 ◽

Vol 114 (1) ◽

pp. 463-475

Author(s):

S. Ishijima ◽

H. Mohri

Keyword(s):

Sea Urchin ◽

Golden Hamster ◽

Large Amplitude ◽

Quantitative Description ◽

Low Frequency ◽

Before And After ◽

Epididymal Spermatozoa ◽

Triton X ◽

Sea Urchin Sperm

Flagellar movement of golden hamster spermatozoa obtained from the testis and the caput and cauda epididymides was observed by a light microscope while holding them at their heads with a micropipette. Flagellar movement of capacitated spermatozoa and of reactivated spermatozoa demembranated with Triton X-100 was also observed. Testicular and caput epididymal spermatozoa showed weak movement in Tyrode's solution, whereas cauda epididymal spermatozoa showed vigorous movement. The flagellar bends of the cauda epididymal spermatozoa were almost planar. Capacitated spermatozoa moved with waves of a large amplitude. Demembranated spermatozoa reactivated with ATP only had a latent period before the initiation of flagellar movement, and beat at low frequency, whereas demembranated spermatozoa reactivated with both ATP and cAMP began to move immediately at high frequency. Thrust and hydrodynamic power output were calculated using the parameters for the typical waveforms of cauda epididymal spermatozoa before and after capacitation. The possible role of the large amplitude beat in capacitated spermatozoa is discussed. A comparison of the ‘principal’ and ‘reverse’ bends in golden hamster sperm flagella as defined by Woolley (1977) with those in sea urchin sperm flagella suggests that the so-called ‘principal’ bend in golden hamster sperm flagella corresponds to the reverse bend in sea urchin sperm flagella and vice versa.

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